Programs & Examples On #Encoder

FlutterError: Unable to load asset

I had the same error when trying to add an image to a module inside a larger project turns out the Image.asset widget takes a packages parameter that you can specify, after specifying it worked just fine

LabelEncoder: TypeError: '>' not supported between instances of 'float' and 'str'

As string data types have variable length, it is by default stored as object type. I faced this problem after treating missing values too. Converting all those columns to type 'category' before label encoding worked in my case.

df[cat]=df[cat].astype('category')

And then check df.dtypes and perform label encoding.

TypeError: Object of type 'bytes' is not JSON serializable

I was dealing with this issue today, and I knew that I had something encoded as a bytes object that I was trying to serialize as json with json.dump(my_json_object, write_to_file.json). my_json_object in this case was a very large json object that I had created, so I had several dicts, lists, and strings to look at to find what was still in bytes format.

The way I ended up solving it: the write_to_file.json will have everything up to the bytes object that is causing the issue.

In my particular case this was a line obtained through

for line in text:
    json_object['line'] = line.strip()

I solved by first finding this error with the help of the write_to_file.json, then by correcting it to:

for line in text:
    json_object['line'] = line.strip().decode()

Angular 2 http post params and body

Let said our backend looks like this:

public async Task<IActionResult> Post([FromBody] IList<UserRol> roles, string notes) {
}

We have a HttpService like this:

    post<T>(url: string, body: any, headers?: HttpHeaders, params?: HttpParams): Observable<T> {
        return this.http.post<T>(url, body, { headers: headers, params});
    }

Following is how we can pass the body and the notes as parameter: // how to call it

const headers: HttpHeaders = new HttpHeaders({
    'Authorization': `Bearer XXXXXXXXXXXXXXXXXXXXXXXXXXX`
});

const bodyData = this.getBodyData(); // get whatever we want to send as body

let params: HttpParams = new HttpParams();
params = params.set('notes', 'Some notes to send');

this.httpService.post<any>(url, bodyData, headers, params);

It worked for me (using angular 7^), I hope is useful for somebody.

Python "TypeError: unhashable type: 'slice'" for encoding categorical data

X is a dataframe and can't be accessed via slice terminology like X[:, 3]. You must access via iloc or X.values. However, the way you constructed X made it a copy... so. I'd use values

# Importing the libraries
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd

# Importing the dataset
# dataset = pd.read_csv('50_Startups.csv')

dataset = pd.DataFrame(np.random.rand(10, 10))
y=dataset.iloc[:, 4]
X=dataset.iloc[:, 0:4]

# Encoding categorical data
from sklearn.preprocessing import LabelEncoder, OneHotEncoder
labelencoder_X = LabelEncoder()

#  I changed this line
X.values[:, 3] = labelencoder_X.fit_transform(X.values[:, 3])

How to save final model using keras?

you can save the model in json and weights in a hdf5 file format.

# keras library import  for Saving and loading model and weights

from keras.models import model_from_json
from keras.models import load_model

# serialize model to JSON
#  the keras model which is trained is defined as 'model' in this example
model_json = model.to_json()


with open("model_num.json", "w") as json_file:
    json_file.write(model_json)

# serialize weights to HDF5
model.save_weights("model_num.h5")

files "model_num.h5" and "model_num.json" are created which contain our model and weights

To use the same trained model for further testing you can simply load the hdf5 file and use it for the prediction of different data. here's how to load the model from saved files.

# load json and create model
json_file = open('model_num.json', 'r')

loaded_model_json = json_file.read()
json_file.close()
loaded_model = model_from_json(loaded_model_json)

# load weights into new model
loaded_model.load_weights("model_num.h5")
print("Loaded model from disk")

loaded_model.save('model_num.hdf5')
loaded_model=load_model('model_num.hdf5')

To predict for different data you can use this

loaded_model.predict_classes("your_test_data here")

iloc giving 'IndexError: single positional indexer is out-of-bounds'

This error is caused by:

Y = Dataset.iloc[:,18].values

Indexing is out of bounds here most probably because there are less than 19 columns in your Dataset, so column 18 does not exist. The following code you provided doesn't use Y at all, so you can just comment out this line for now.

How do I get rid of the b-prefix in a string in python?

On python 3.6 with django 2.0, decode on a byte literal does not works as expected. Yeah i get the right result when i print it, but the b'value' is still there even if you print it right.

This is what im encoding

uid': urlsafe_base64_encode(force_bytes(user.pk)),

This is what im decoding:

uid = force_text(urlsafe_base64_decode(uidb64))

This is what django 2.0 says :

urlsafe_base64_encode(s)[source]

Encodes a bytestring in base64 for use in URLs, stripping any trailing equal signs.

urlsafe_base64_decode(s)[source]

Decodes a base64 encoded string, adding back any trailing equal signs that might have been stripped.


This is my account_activation_email_test.html file

{% autoescape off %}
Hi {{ user.username }},

Please click on the link below to confirm your registration:

http://{{ domain }}{% url 'accounts:activate' uidb64=uid token=token %}
{% endautoescape %}

This is my console response:

Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Activate Your MySite Account From: webmaster@localhost To: [email protected] Date: Fri, 20 Apr 2018 06:26:46 -0000 Message-ID: <152420560682.16725.4597194169307598579@Dash-U>

Hi testuser,

Please click on the link below to confirm your registration:

http://127.0.0.1:8000/activate/b'MjU'/4vi-fasdtRf2db2989413ba/

as you can see uid = b'MjU'

expected uid = MjU


test in console:

$ python
Python 3.6.4 (default, Apr  7 2018, 00:45:33) 
[GCC 5.4.0 20160609] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from django.utils.http import urlsafe_base64_encode, urlsafe_base64_decode
>>> from django.utils.encoding import force_bytes, force_text
>>> var1=urlsafe_base64_encode(force_bytes(3))
>>> print(var1)
b'Mw'
>>> print(var1.decode())
Mw
>>> 

After investigating it seems like its related to python 3. My workaround was quite simple:

'uid': user.pk,

i receive it as uidb64 on my activate function:

user = User.objects.get(pk=uidb64)

and voila:

Content-Transfer-Encoding: 7bit
Subject: Activate Your MySite Account
From: webmaster@localhost
To: [email protected]
Date: Fri, 20 Apr 2018 20:44:46 -0000
Message-ID: <152425708646.11228.13738465662759110946@Dash-U>


Hi testuser,

Please click on the link below to confirm your registration:

http://127.0.0.1:8000/activate/45/4vi-3895fbb6b74016ad1882/

now it works fine. :)

How to convert an Image to base64 string in java?

I think you might want:

String encodedFile = Base64.getEncoder().encodeToString(bytes);

disabling spring security in spring boot app

Change WebSecurityConfig.java: comment out everything in the configure method and add

http.authenticateRequest().antMatcher("/**").permitAll();

This will allow any request to hit every URL without any authentication.

How do I enable logging for Spring Security?

Assuming you're using Spring Boot, another option is to put the following in your application.properties:

logging.level.org.springframework.security=DEBUG

This is the same for most other Spring modules as well.

If you're not using Spring Boot, try setting the property in your logging configuration, e.g. logback.

Here is the application.yml version as well:

logging:
  level:
    org:
      springframework:
        security: DEBUG

How to fix Invalid AES key length?

You can use this code, this code is for AES-256-CBC or you can use it for other AES encryption. Key length error mainly comes in 256-bit encryption.

This error comes due to the encoding or charset name we pass in the SecretKeySpec. Suppose, in my case, I have a key length of 44, but I am not able to encrypt my text using this long key; Java throws me an error of invalid key length. Therefore I pass my key as a BASE64 in the function, and it converts my 44 length key in the 32 bytes, which is must for the 256-bit encryption.

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.MessageDigest;
import java.security.Security;
import java.util.Base64;

public class Encrypt {

    static byte [] arr = {1,2,3,4,5,6,7,8,9};

    // static byte [] arr = new byte[16];

      public static void main(String...args) {
        try {
         //   System.out.println(Cipher.getMaxAllowedKeyLength("AES"));
            Base64.Decoder decoder = Base64.getDecoder();
            // static byte [] arr = new byte[16];
            Security.setProperty("crypto.policy", "unlimited");
            String key = "Your key";
       //     System.out.println("-------" + key);

            String value = "Hey, i am adnan";
            String IV = "0123456789abcdef";
       //     System.out.println(value);
            // log.info(value);
          IvParameterSpec iv = new IvParameterSpec(IV.getBytes());
            //    IvParameterSpec iv = new IvParameterSpec(arr);

        //    System.out.println(key);
            SecretKeySpec skeySpec = new SecretKeySpec(decoder.decode(key), "AES");
         //   System.out.println(skeySpec);
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        //    System.out.println("ddddddddd"+IV);
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
       //     System.out.println(cipher.getIV());

            byte[] encrypted = cipher.doFinal(value.getBytes());
            String encryptedString = Base64.getEncoder().encodeToString(encrypted);

            System.out.println("encrypted string,,,,,,,,,,,,,,,,,,,: " + encryptedString);
            // vars.put("input-1",encryptedString);
            //  log.info("beanshell");
        }catch (Exception e){
            System.out.println(e.getMessage());
        }
    }
}

Spring boot - Not a managed type

Below worked for me..

import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

import org.apache.catalina.security.SecurityConfig;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.domain.EntityScan;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.test.context.web.WebAppConfiguration;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.context.WebApplicationContext;

import com.something.configuration.SomethingConfig;

@RunWith(SpringRunner.class)
@SpringBootTest(classes = { SomethingConfig.class, SecurityConfig.class }) //All your configuration classes
@EnableAutoConfiguration
@WebAppConfiguration // for MVC configuration
@EnableJpaRepositories("com.something.persistence.dataaccess")  //JPA repositories
@EntityScan("com.something.domain.entity.*")  //JPA entities
@ComponentScan("com.something.persistence.fixture") //any component classes you have
public class SomethingApplicationTest {

    @Autowired
    private WebApplicationContext ctx;
    private MockMvc mockMvc;

    @Before
    public void setUp() {
        this.mockMvc = MockMvcBuilders.webAppContextSetup(ctx).build();
    }

    @Test
    public void loginTest() throws Exception {
        this.mockMvc.perform(get("/something/login"))
        .andDo(print()).andExpect(status().isOk());
    }

}

Base64: java.lang.IllegalArgumentException: Illegal character

The Base64.Encoder.encodeToString method automatically uses the ISO-8859-1 character set.

For an encryption utility I am writing, I took the input string of cipher text and Base64 encoded it for transmission, then reversed the process. Relevant parts shown below. NOTE: My file.encoding property is set to ISO-8859-1 upon invocation of the JVM so that may also have a bearing.

static String getBase64EncodedCipherText(String cipherText) {
    byte[] cText = cipherText.getBytes();
    // return an ISO-8859-1 encoded String
    return Base64.getEncoder().encodeToString(cText);
}

static String getBase64DecodedCipherText(String encodedCipherText) throws IOException {
    return new String((Base64.getDecoder().decode(encodedCipherText)));
}

public static void main(String[] args) {
    try {
        String cText = getRawCipherText(null, "Hello World of Encryption...");

        System.out.println("Text to encrypt/encode: Hello World of Encryption...");
        // This output is a simple sanity check to display that the text
        // has indeed been converted to a cipher text which 
        // is unreadable by all but the most intelligent of programmers.
        // It is absolutely inhuman of me to do such a thing, but I am a
        // rebel and cannot be trusted in any way.  Please look away.
        System.out.println("RAW CIPHER TEXT: " + cText);
        cText = getBase64EncodedCipherText(cText);
        System.out.println("BASE64 ENCODED: " + cText);
        // There he goes again!!
        System.out.println("BASE64 DECODED:  " + getBase64DecodedCipherText(cText));
        System.out.println("DECODED CIPHER TEXT: " + decodeRawCipherText(null, getBase64DecodedCipherText(cText)));
    } catch (Exception e) {
        e.printStackTrace();
    }

}

The output looks like:

Text to encrypt/encode: Hello World of Encryption...
RAW CIPHER TEXT: q$;?C?l??<8??U???X[7l
BASE64 ENCODED: HnEPJDuhQ+qDbInUCzw4gx0VDqtVwef+WFs3bA==
BASE64 DECODED:  q$;?C?l??<8??U???X[7l``
DECODED CIPHER TEXT: Hello World of Encryption...

Label encoding across multiple columns in scikit-learn

Following up on the comments raised on the solution of @PriceHardman I would propose the following version of the class:

class LabelEncodingColoumns(BaseEstimator, TransformerMixin):
def __init__(self, cols=None):
    pdu._is_cols_input_valid(cols)
    self.cols = cols
    self.les = {col: LabelEncoder() for col in cols}
    self._is_fitted = False

def transform(self, df, **transform_params):
    """
    Scaling ``cols`` of ``df`` using the fitting

    Parameters
    ----------
    df : DataFrame
        DataFrame to be preprocessed
    """
    if not self._is_fitted:
        raise NotFittedError("Fitting was not preformed")
    pdu._is_cols_subset_of_df_cols(self.cols, df)

    df = df.copy()

    label_enc_dict = {}
    for col in self.cols:
        label_enc_dict[col] = self.les[col].transform(df[col])

    labelenc_cols = pd.DataFrame(label_enc_dict,
        # The index of the resulting DataFrame should be assigned and
        # equal to the one of the original DataFrame. Otherwise, upon
        # concatenation NaNs will be introduced.
        index=df.index
    )

    for col in self.cols:
        df[col] = labelenc_cols[col]
    return df

def fit(self, df, y=None, **fit_params):
    """
    Fitting the preprocessing

    Parameters
    ----------
    df : DataFrame
        Data to use for fitting.
        In many cases, should be ``X_train``.
    """
    pdu._is_cols_subset_of_df_cols(self.cols, df)
    for col in self.cols:
        self.les[col].fit(df[col])
    self._is_fitted = True
    return self

This class fits the encoder on the training set and uses the fitted version when transforming. Initial version of the code can be found here.

java IO Exception: Stream Closed

You call writer.close(); in writeToFile so the writer has been closed the second time you call writeToFile.

Why don't you merge FileStatus into writeToFile?

UnicodeDecodeError: 'utf8' codec can't decode byte 0xa5 in position 0: invalid start byte

Simple Solution:

import pandas as pd
df = pd.read_csv('file_name.csv', engine='python')

java.net.MalformedURLException: no protocol on URL based on a string modified with URLEncoder

This code worked for me

public static void main(String[] args) {
    try {
        java.net.URL myUr = new java.net.URL("http://path");
        System.out.println("Instantiated new URL: " + connection_url);
    }
    catch (MalformedURLException e) {
        e.printStackTrace();
    }
}

Instantiated new URL: http://path

How To Inject AuthenticationManager using Java Configuration in a Custom Filter

In addition to what Angular University said above you may want to use @Import to aggregate @Configuration classes to the other class (AuthenticationController in my case) :

@Import(SecurityConfig.class)
@RestController
public class AuthenticationController {
@Autowired
private AuthenticationManager authenticationManager;
//some logic
}

Spring doc about Aggregating @Configuration classes with @Import: link

How can I send large messages with Kafka (over 15MB)?

For people using landoop kafka: You can pass the config values in the environment variables like:

docker run -d --rm -p 2181:2181 -p 3030:3030 -p 8081-8083:8081-8083  -p 9581-9585:9581-9585 -p 9092:9092
 -e KAFKA_TOPIC_MAX_MESSAGE_BYTES=15728640 -e KAFKA_REPLICA_FETCH_MAX_BYTES=15728640  landoop/fast-data-dev:latest `

And if you're usind rdkafka then pass the message.max.bytes in the producer config like:

  const producer = new Kafka.Producer({
        'metadata.broker.list': 'localhost:9092',
        'message.max.bytes': '15728640',
        'dr_cb': true
    });

Similarly, for the consumer,

  const kafkaConf = {
   "group.id": "librd-test",
   "fetch.message.max.bytes":"15728640",
   ... .. }                                                                                                                                                                                                                                                      

How to get coordinates of an svg element?

The way to determine the coordinates depends on what element you're working with. For circles for example, the cx and cy attributes determine the center position. In addition, you may have a translation applied through the transform attribute which changes the reference point of any coordinates.

Most of the ways used in general to get screen coordinates won't work for SVGs. In addition, you may not want absolute coordinates if the line you want to draw is in the same container as the elements it connects.

Edit:

In your particular code, it's quite difficult to get the position of the node because its determined by a translation of the parent element. So you need to get the transform attribute of the parent node and extract the translation from that.

d3.transform(d3.select(this.parentNode).attr("transform")).translate

Working jsfiddle here.

Cutting the videos based on start and end time using ffmpeg

Even though I'm 6 years late, but I think all the answers above didn't properly address the question @kalai is asking. The bash script below will process a text file in the following format:

URL | start_time | end_time | filename

for example

https://www.youtube.com/watch?v=iUDURCrvrMI|00:02:02|00:03:41|1

and loop through the file, downloads the file that youtube-dl supports, calculating duration between start_time and end_time and passing it to ffmpeg, since -t is actually the duration, not the real end_time

Hit me up if you have any question.

    for i in $(<video.txt);
    do
        URL=`echo $i | cut -d "|" -f 1`;
        START=`echo $i | cut -d "|" -f 2`;
        END=`echo $i | cut -d "|" -f 3`;
        FILE=`echo $i | cut -d "|" -f 4`;

        SEC1=`echo $START | sed 's/^/((/; s/:/)*60+/g' | bc`
        SEC2=`echo $END | sed 's/^/((/; s/:/)*60+/g' | bc`

        DIFFSEC=`expr ${SEC2} - ${SEC1}`

        ffmpeg $(youtube-dl -g $URL | sed "s/.*/-ss $START -i &/") -t $DIFFSEC -c copy $FILE".mkv";
        ffmpeg -i $FILE".mkv" -f mp3 -ab 192000 -vn $FILE".mp3";
        rm $FILE".mkv";
    done;

Toggle visibility property of div

To do it with an effect like with $.fadeIn() and $.fadeOut() you can use transitions

.visible {
  visibility: visible;
  opacity: 1;
  transition: opacity 1s linear;
}
.hidden {
  visibility: hidden;
  opacity: 0;
  transition: visibility 0s 1s, opacity 1s linear;
}

How to use new PasswordEncoder from Spring Security

If you haven't actually registered any users with your existing format then you would be best to switch to using the BCrypt password encoder instead.

It's a lot less hassle, as you don't have to worry about salt at all - the details are completely encapsulated within the encoder. Using BCrypt is stronger than using a plain hash algorithm and it's also a standard which is compatible with applications using other languages.

There's really no reason to choose any of the other options for a new application.

Removing fields from struct or hiding them in JSON Response

The question is now a bit old, but I came across the same issue a little while ago, and as I found no easy way to do this, I built a library fulfilling this purpose. It allows to easily generate a map[string]interface{} from a static struct.

https://github.com/tuvistavie/structomap

javax.crypto.IllegalBlockSizeException : Input length must be multiple of 16 when decrypting with padded cipher

Well that is Because of

you are only able to encrypt data in blocks of 128 bits or 16 bytes. That's why you are getting that IllegalBlockSizeException exception. and the one way is to encrypt that data Directly into the String.

look this. Try and u will be able to resolve this

public static String decrypt(String encryptedData) throws Exception {

    Key key = generateKey();
    Cipher c = Cipher.getInstance(ALGO);
    c.init(Cipher.DECRYPT_MODE, key);
    String decordedValue = new BASE64Decoder().decodeBuffer(encryptedData).toString().trim();
    System.out.println("This is Data to be Decrypted" + decordedValue);
    return decordedValue;
}

hope that will help.

SeekBar and media player in android

Given the answer hardartcore that worked for me with a small change and did not work before the change:

private Handler mHandler = new Handler();
MusicPlayer.this.runOnUiThread(new Runnable() {
     @Override
     public void run() {
          if(player != null){
               int mCurrentPosition = player.getCurrentPosition();//clear ' /1000 '
               seekBar.setProgress(mCurrentPosition);
          }
          mHandler.postDelayed(this, 1000);
      }
});



seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {

    @Override
    public void onStopTrackingTouch(SeekBar seekBar) {

    }

    @Override
    public void onStartTrackingTouch(SeekBar seekBar) {

    }

    @Override
    public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
          if(player != null && fromUser){
              player.seekTo(progress); // clear ' * 1000  '
          }
     }
});

Output Django queryset as JSON

Try this:

class JSONListView(ListView):
    queryset = Users.objects.all()


    def get(self, request, *args, **kwargs):
        data = {}
        data["users"] = get_json_list(queryset)
        return JSONResponse(data)


def get_json_list(query_set):
    list_objects = []
    for obj in query_set:
        dict_obj = {}
        for field in obj._meta.get_fields():
            try:
                if field.many_to_many:
                    dict_obj[field.name] = get_json_list(getattr(obj, field.name).all())
                    continue
                dict_obj[field.name] = getattr(obj, field.name)
            except AttributeError:
                continue
        list_objects.append(dict_obj)
    return list_objects

The content type application/xml;charset=utf-8 of the response message does not match the content type of the binding (text/xml; charset=utf-8)

Try browse the WCF in IIS see if it's alive and works normally,

In my case it's because the physical path of the WCF is misdirected.

python encoding utf-8

You don't need to encode data that is already encoded. When you try to do that, Python will first try to decode it to unicode before it can encode it back to UTF-8. That is what is failing here:

>>> data = u'\u00c3'            # Unicode data
>>> data = data.encode('utf8')  # encoded to UTF-8
>>> data
'\xc3\x83'
>>> data.encode('utf8')         # Try to *re*-encode it
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 0: ordinal not in range(128)

Just write your data directly to the file, there is no need to encode already-encoded data.

If you instead build up unicode values instead, you would indeed have to encode those to be writable to a file. You'd want to use codecs.open() instead, which returns a file object that will encode unicode values to UTF-8 for you.

You also really don't want to write out the UTF-8 BOM, unless you have to support Microsoft tools that cannot read UTF-8 otherwise (such as MS Notepad).

For your MySQL insert problem, you need to do two things:

  • Add charset='utf8' to your MySQLdb.connect() call.

  • Use unicode objects, not str objects when querying or inserting, but use sql parameters so the MySQL connector can do the right thing for you:

    artiste = artiste.decode('utf8')  # it is already UTF8, decode to unicode
    
    c.execute('SELECT COUNT(id) AS nbr FROM artistes WHERE nom=%s', (artiste,))
    
    # ...
    
    c.execute('INSERT INTO artistes(nom,status,path) VALUES(%s, 99, %s)', (artiste, artiste + u'/'))
    

It may actually work better if you used codecs.open() to decode the contents automatically instead:

import codecs

sql = mdb.connect('localhost','admin','ugo&(-@F','music_vibration', charset='utf8')

with codecs.open('config/index/'+index, 'r', 'utf8') as findex:
    for line in findex:
        if u'#artiste' not in line:
            continue

        artiste=line.split(u'[:::]')[1].strip()

    cursor = sql.cursor()
    cursor.execute('SELECT COUNT(id) AS nbr FROM artistes WHERE nom=%s', (artiste,))
    if not cursor.fetchone()[0]:
        cursor = sql.cursor()
        cursor.execute('INSERT INTO artistes(nom,status,path) VALUES(%s, 99, %s)', (artiste, artiste + u'/'))
        artists_inserted += 1

You may want to brush up on Unicode and UTF-8 and encodings. I can recommend the following articles:

Uri not Absolute exception getting while calling Restful Webservice

For others who landed in this error and it's not 100% related to the OP question, please check that you are passing the value and it is not null in case of spring-boot: @Value annotation.

How do I fix the error "Only one usage of each socket address (protocol/network address/port) is normally permitted"?

ListenForClients is getting invoked twice (on two different threads) - once from the constructor, once from the explicit method call in Main. When two instances of the TcpListener try to listen on the same port, you get that error.

HttpWebRequest-The remote server returned an error: (400) Bad Request

Are you sure you should be using POST not PUT?

POST is usually used with application/x-www-urlencoded formats. If you are using a REST API, you should maybe be using PUT? If you are uploading a file you probably need to use multipart/form-data. Not always, but usually, that is the right thing to do..

Also you don't seem to be using the credentials to log in - you need to use the Credentials property of the HttpWebRequest object to send the username and password.

Encoding as Base64 in Java

Google Guava is another choice to encode and decode Base64 data:

POM configuration:

<dependency>
   <artifactId>guava</artifactId>
   <groupId>com.google.guava</groupId>
   <type>jar</type>
   <version>14.0.1</version>
</dependency>

Sample code:

String inputContent = "Hello Vi?t Nam";
String base64String = BaseEncoding.base64().encode(inputContent.getBytes("UTF-8"));

// Decode
System.out.println("Base64:" + base64String); // SGVsbG8gVmnhu4d0IE5hbQ==
byte[] contentInBytes = BaseEncoding.base64().decode(base64String);
System.out.println("Source content: " + new String(contentInBytes, "UTF-8")); // Hello Vi?t Nam

Loading and parsing a JSON file with multiple JSON objects

You have a JSON Lines format text file. You need to parse your file line by line:

import json

data = []
with open('file') as f:
    for line in f:
        data.append(json.loads(line))

Each line contains valid JSON, but as a whole, it is not a valid JSON value as there is no top-level list or object definition.

Note that because the file contains JSON per line, you are saved the headaches of trying to parse it all in one go or to figure out a streaming JSON parser. You can now opt to process each line separately before moving on to the next, saving memory in the process. You probably don't want to append each result to one list and then process everything if your file is really big.

If you have a file containing individual JSON objects with delimiters in-between, use How do I use the 'json' module to read in one JSON object at a time? to parse out individual objects using a buffered method.

ffmpeg - Converting MOV files to MP4

The command to just stream it to a new container (mp4) needed by some applications like Adobe Premiere Pro without encoding (fast) is:

ffmpeg -i input.mov -qscale 0 output.mp4

Alternative as mentioned in the comments, which re-encodes with best quaility (-qscale 0):

ffmpeg -i input.mov -q:v 0 output.mp4

The type or namespace name does not exist in the namespace 'System.Web.Mvc'

You need to update MVC.

  1. Go to Tools -> NuGet Package Manager -> Manage NuGet Packages for Solution
  2. Click on "Updates"
  3. Update "Microsoft ASP.NET MVC"
  4. Rebuild Solution

json.dump throwing "TypeError: {...} is not JSON serializable" on seemingly valid object?

I wrote a class to normalize the data in my dictionary. The 'element' in the NormalizeData class below, needs to be of dict type. And you need to replace in the __iterate() with either your custom class object or any other object type that you would like to normalize.

class NormalizeData:

    def __init__(self, element):
        self.element = element

    def execute(self):
        if isinstance(self.element, dict):
            self.__iterate()
        else:
            return

    def __iterate(self):
        for key in self.element:
            if isinstance(self.element[key], <ClassName>):
                self.element[key] = str(self.element[key])

            node = NormalizeData(self.element[key])
            node.execute()

Java URL encoding of query string parameters

  1. Use this: URLEncoder.encode(query, StandardCharsets.UTF_8.displayName()); or this:URLEncoder.encode(query, "UTF-8");
  2. You can use the follwing code.

    String encodedUrl1 = UriUtils.encodeQuery(query, "UTF-8");//not change 
    String encodedUrl2 = URLEncoder.encode(query, "UTF-8");//changed
    String encodedUrl3 = URLEncoder.encode(query, StandardCharsets.UTF_8.displayName());//changed
    
    System.out.println("url1 " + encodedUrl1 + "\n" + "url2=" + encodedUrl2 + "\n" + "url3=" + encodedUrl3);
    

Unable to instantiate default tuplizer [org.hibernate.tuple.entity.PojoEntityTuplizer]

I had a similar problem and after going over a lot on stack overflow and spending time on the jar dependencies, I figured out that in my case, I had two sets of asm.jar. I removed one of them and it worked fine...

Use ffmpeg to add text subtitles

Simple Example:

videoSource=test.mp4
videoEncoded=test2.mp4
videoSubtitle=test.srt
videoFontSize=24
ffmpeg -i "$videoSource" -vf subtitles="$videoSubtitle":force_style='Fontsize="$videoFontSize"' "$videoEncoded"

Only replace the linux variables

How to convert String to DOM Document object in java?

you can try

DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader("<root><node1></node1></root>"));

Document doc = db.parse(is);

refer this http://www.java2s.com/Code/Java/XML/ParseanXMLstringUsingDOMandaStringReader.htm

How to JSON serialize sets?

One shortcoming of the accepted solution is that its output is very python specific. I.e. its raw json output cannot be observed by a human or loaded by another language (e.g. javascript). example:

db = {
        "a": [ 44, set((4,5,6)) ],
        "b": [ 55, set((4,3,2)) ]
        }

j = dumps(db, cls=PythonObjectEncoder)
print(j)

Will get you:

{"a": [44, {"_python_object": "gANjYnVpbHRpbnMKc2V0CnEAXXEBKEsESwVLBmWFcQJScQMu"}], "b": [55, {"_python_object": "gANjYnVpbHRpbnMKc2V0CnEAXXEBKEsCSwNLBGWFcQJScQMu"}]}

I can propose a solution which downgrades the set to a dict containing a list on the way out, and back to a set when loaded into python using the same encoder, therefore preserving observability and language agnosticism:

from decimal import Decimal
from base64 import b64encode, b64decode
from json import dumps, loads, JSONEncoder
import pickle

class PythonObjectEncoder(JSONEncoder):
    def default(self, obj):
        if isinstance(obj, (list, dict, str, int, float, bool, type(None))):
            return super().default(obj)
        elif isinstance(obj, set):
            return {"__set__": list(obj)}
        return {'_python_object': b64encode(pickle.dumps(obj)).decode('utf-8')}

def as_python_object(dct):
    if '__set__' in dct:
        return set(dct['__set__'])
    elif '_python_object' in dct:
        return pickle.loads(b64decode(dct['_python_object'].encode('utf-8')))
    return dct

db = {
        "a": [ 44, set((4,5,6)) ],
        "b": [ 55, set((4,3,2)) ]
        }

j = dumps(db, cls=PythonObjectEncoder)
print(j)
ob = loads(j)
print(ob["a"])

Which gets you:

{"a": [44, {"__set__": [4, 5, 6]}], "b": [55, {"__set__": [2, 3, 4]}]}
[44, {'__set__': [4, 5, 6]}]

Note that serializing a dictionary which has an element with a key "__set__" will break this mechanism. So __set__ has now become a reserved dict key. Obviously feel free to use another, more deeply obfuscated key.

Get Base64 encode file-data from Input Form

It's entirely possible in browser-side javascript.

The easy way:

The readAsDataURL() method might already encode it as base64 for you. You'll probably need to strip out the beginning stuff (up to the first ,), but that's no biggie. This would take all the fun out though.

The hard way:

If you want to try it the hard way (or it doesn't work), look at readAsArrayBuffer(). This will give you a Uint8Array and you can use the method specified. This is probably only useful if you want to mess with the data itself, such as manipulating image data or doing other voodoo magic before you upload.

There are two methods:

  • Convert to string and use the built-in btoa or similar
    • I haven't tested all cases, but works for me- just get the char-codes
  • Convert directly from a Uint8Array to base64

I recently implemented tar in the browser. As part of that process, I made my own direct Uint8Array->base64 implementation. I don't think you'll need that, but it's here if you want to take a look; it's pretty neat.

What I do now:

The code for converting to string from a Uint8Array is pretty simple (where buf is a Uint8Array):

function uint8ToString(buf) {
    var i, length, out = '';
    for (i = 0, length = buf.length; i < length; i += 1) {
        out += String.fromCharCode(buf[i]);
    }
    return out;
}

From there, just do:

var base64 = btoa(uint8ToString(yourUint8Array));

Base64 will now be a base64-encoded string, and it should upload just peachy. Try this if you want to double check before pushing:

window.open("data:application/octet-stream;base64," + base64);

This will download it as a file.

Other info:

To get the data as a Uint8Array, look at the MDN docs:

Encoding Javascript Object to Json string

You can use JSON.stringify like:

JSON.stringify(new_tweets);

How long to brute force a salted SHA-512 hash? (salt provided)

There isn't a single answer to this question as there are too many variables, but SHA2 is not yet really cracked (see: Lifetimes of cryptographic hash functions) so it is still a good algorithm to use to store passwords in. The use of salt is good because it prevents attack from dictionary attacks or rainbow tables. Importance of a salt is that it should be unique for each password. You can use a format like [128-bit salt][512-bit password hash] when storing the hashed passwords.

The only viable way to attack is to actually calculate hashes for different possibilities of password and eventually find the right one by matching the hashes.

To give an idea about how many hashes can be done in a second, I think Bitcoin is a decent example. Bitcoin uses SHA256 and to cut it short, the more hashes you generate, the more bitcoins you get (which you can trade for real money) and as such people are motivated to use GPUs for this purpose. You can see in the hardware overview that an average graphic card that costs only $150 can calculate more than 200 million hashes/s. The longer and more complex your password is, the longer time it will take. Calculating at 200M/s, to try all possibilities for an 8 character alphanumberic (capital, lower, numbers) will take around 300 hours. The real time will most likely less if the password is something eligible or a common english word.

As such with anything security you need to look at in context. What is the attacker's motivation? What is the kind of application? Having a hash with random salt for each gives pretty good protection against cases where something like thousands of passwords are compromised.

One thing you can do is also add additional brute force protection by slowing down the hashing procedure. As you only hash passwords once, and the attacker has to do it many times, this works in your favor. The typical way to do is to take a value, hash it, take the output, hash it again and so forth for a fixed amount of iterations. You can try something like 1,000 or 10,000 iterations for example. This will make it that many times times slower for the attacker to find each password.

How to encode Doctrine entities to JSON in Symfony 2.0 AJAX application?

When you need to create a lot of REST API endpoints on Symfony, the best way is to use following stack of bundles:

  1. JMSSerializerBundle for the serialization of Doctrine entities
  2. FOSRestBundle bundle for response view listener. Also it can generate definition of routes based on controller/action name.
  3. NelmioApiDocBundle to auto-generate online documentation and Sandbox(which allows to test endpoint without any external tool).

When you configure everything properly, you entity code will look like:

use Doctrine\ORM\Mapping as ORM;
use JMS\Serializer\Annotation as JMS;

/**
 * @ORM\Table(name="company")
 */
class Company
{

    /**
     * @var string
     *
     * @ORM\Column(name="name", type="string", length=255)
     *
     * @JMS\Expose()
     * @JMS\SerializedName("name")
     * @JMS\Groups({"company_overview"})
     */
    private $name;

    /**
     * @var Campaign[]
     *
     * @ORM\OneToMany(targetEntity="Campaign", mappedBy="company")
     * 
     * @JMS\Expose()
     * @JMS\SerializedName("campaigns")
     * @JMS\Groups({"campaign_overview"})
     */
    private $campaigns;
}

Then, code in controller:

use Nelmio\ApiDocBundle\Annotation\ApiDoc;
use FOS\RestBundle\Controller\Annotations\View;

class CompanyController extends Controller
{

    /**
     * Retrieve all companies
     *
     * @View(serializerGroups={"company_overview"})
     * @ApiDoc()
     *
     * @return Company[]
     */
    public function cgetAction()
    {
        return $this->getDoctrine()->getRepository(Company::class)->findAll();
    }
}

The benefits of such set up are:

  • @JMS\Expose() annotations in entity can be added to simple fields, and to any types of relations. Also there is possibility to expose result of some method execution (use annotation @JMS\VirtualProperty() for that)
  • With serialization groups we can control exposed fields in different situations.
  • Controllers are very simple. Action method can directly return an entity or array of entities, and they will be automatically serialized.
  • And @ApiDoc() allows to test the endpoint directly from browser, without any REST client or JavaScript code

InvalidKeyException : Illegal Key Size - Java code throwing exception for encryption class - how to fix?

The error seems to be thrown when you try and load they keystore from "C:/jakarta-tomcat/webapps/PlanB/Certs/my_pkcs12.p12" here:

ks.load( new FileInputStream(_privateKeyPath), _keyPass.toCharArray() ); 

Have you tried replaceing "/" with "\\" in your file path? If that doesn't help it probably has to do with Java's Unlimited Strength Jurisdiction Policy Files. You could check this by writing a little program that does AES encryption. Try encrypting with a 128 bit key, then if that works, try with a 256 bit key and see if it fails.

Code that does AES encyrption:

import java.io.UnsupportedEncodingException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class Test 
{
    final String ALGORITHM = "AES";                       //symmetric algorithm for data encryption
    final String PADDING_MODE = "/CBC/PKCS5Padding";      //Padding for symmetric algorithm
    final String CHAR_ENCODING = "UTF-8";                 //character encoding
    //final String CRYPTO_PROVIDER = "SunMSCAPI";             //provider for the crypto

    int AES_KEY_SIZE = 256;  //symmetric key size (128, 192, 256) if using 256 you must have the Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files  installed

    private String doCrypto(String plainText) throws NoSuchAlgorithmException, NoSuchProviderException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException, InvalidAlgorithmParameterException, UnsupportedEncodingException
    {
        byte[] dataToEncrypt = plainText.getBytes(CHAR_ENCODING);

        //get the symmetric key generator
        KeyGenerator keyGen = KeyGenerator.getInstance(ALGORITHM);
        keyGen.init(AES_KEY_SIZE); //set the key size

        //generate the key
        SecretKey skey = keyGen.generateKey();

        //convert to binary
        byte[] rawAesKey = skey.getEncoded();

        //initialize the secret key with the appropriate algorithm
        SecretKeySpec skeySpec = new SecretKeySpec(rawAesKey, ALGORITHM);

        //get an instance of the symmetric cipher
        Cipher aesCipher = Cipher.getInstance(ALGORITHM + PADDING_MODE);

        //set it to encrypt mode, with the generated key
        aesCipher.init(Cipher.ENCRYPT_MODE, skeySpec);

        //get the initialization vector being used (to be returned)
        byte[] aesIV = aesCipher.getIV();

        //encrypt the data
        byte[] encryptedData = aesCipher.doFinal(dataToEncrypt);    

        //initialize the secret key with the appropriate algorithm
        SecretKeySpec skeySpecDec = new SecretKeySpec(rawAesKey, ALGORITHM);

        //get an instance of the symmetric cipher
        Cipher aesCipherDec = Cipher.getInstance(ALGORITHM +PADDING_MODE);

        //set it to decrypt mode with the AES key, and IV
        aesCipherDec.init(Cipher.DECRYPT_MODE, skeySpecDec, new IvParameterSpec(aesIV));

        //decrypt and return the data
        byte[] decryptedData = aesCipherDec.doFinal(encryptedData);

        return new String(decryptedData, CHAR_ENCODING);
    }

    public static void main(String[] args)
    {
        String text = "Lets encrypt me";

        Test test = new Test();

        try {
            System.out.println(test.doCrypto(text));
        } catch (InvalidKeyException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (NoSuchProviderException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (BadPaddingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (InvalidAlgorithmParameterException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

Does this code work for you?

You might also want to try specifying your bouncy castle provider in this line:

Cipher.getInstance(ALGORITHM +PADDING_MODE, "YOUR PROVIDER");

And see if it could be an error associated with bouncy castle.

javascript object max size limit

you have to put this in web.config :

<system.web.extensions>
    <scripting>
      <webServices>
        <jsonSerialization maxJsonLength="50000000" />
      </webServices>
    </scripting>
  </system.web.extensions>

How can I configure Logback to log different levels for a logger to different destinations?

Example of how to output colored messages of level "INFO" or higher to console and messages of level "WARN" or higher to file.

Your logback.xml file:

<?xml version="1.0" encoding="UTF-8"?>

<configuration>
    <include resource="org/springframework/boot/logging/logback/defaults.xml"/>

    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>INFO</level>

            <!--output messages of exact level only-->
            <!--<onMatch>ACCEPT</onMatch>-->
            <!--<onMismatch>DENY</onMismatch>-->
        </filter>
        <encoder>
            <pattern>%d{yyyy-MMM-dd HH:mm:ss.SSS} [%thread] %highlight(%-5level) %cyan(%logger{15}) - %msg %n
            </pattern>
        </encoder>
    </appender>

    <appender name="FILE" class="ch.qos.logback.core.FileAppender">
        <file>myfile.log</file>
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>WARN</level>
        </filter>
        <append>true</append>
        <encoder>
            <pattern>%d{yyyy-MMM-dd HH:mm:ss.SSS} %-5level [%thread] %logger{15} - %msg%n</pattern>
        </encoder>
    </appender>

    <root level="INFO">
        <appender-ref ref="STDOUT" />
        <appender-ref ref="FILE"/>
    </root>
</configuration>

How to screenshot website in JavaScript client-side / how Google did it? (no need to access HDD)

I needed to snapshot a div on the page (for a webapp I wrote) that is protected by JWT's and makes very heavy use of Angular.

I had no luck with any of the above methods.

I ended up taking the outerHTML of the div I needed, cleaning it up a little (*) and then sending it to the server where I run wkhtmltopdf against it.

This is working very well for me.

(*) various input devices in my pages didn't render as checked or have their text values when viewed in the pdf... So I run a little bit of jQuery on the html before I send it up for rendering. ex: for text input items -- I copy their .val()'s into 'value' attributes, which then can be seen by wkhtmlpdf

import sun.misc.BASE64Encoder results in error compiled in Eclipse

This error is because of you are importing below two classes import sun.misc.BASE64Encoder; import sun.misc.BASE64Decoder;. Maybe you are using encode and decode of that library like below.

new BASE64Encoder().encode(encVal);
newBASE64Decoder().decodeBuffer(encryptedData);

Yeah instead of sun.misc.BASE64Encoder you can import java.util.Base64 class.Now change the previous encode method as below:

encryptedData=Base64.getEncoder().encodeToString(encryptedByteArray);

Now change the previous decode method as below

byte[] base64DecodedData = Base64.getDecoder().decode(base64EncodedData);

Now everything is done , you can save your program and run. It will run without showing any error.

Encoding URL query parameters in Java

It is not necessary to encode a colon as %3B in the query, although doing so is not illegal.

URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
query       = *( pchar / "/" / "?" )
pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
unreserved    = ALPHA / DIGIT / "-" / "." / "_" / "~"
pct-encoded   = "%" HEXDIG HEXDIG
sub-delims    = "!" / "$" / "&" / "'" / "(" / ")" / "*" / "+" / "," / ";" / "="

It also seems that only percent-encoded spaces are valid, as I doubt that space is an ALPHA or a DIGIT

look to the URI specification for more details.

WCF Service Client: The content type text/html; charset=utf-8 of the response message does not match the content type of the binding

As with many, in my situation I was also getting this because of an error. And sadly I could just read the CSS of the html error page.

The source of my problem was also a rewrite rule on the server. It was rewriting http to https.

URLEncoder not able to translate space character

Encode Query params

org.apache.commons.httpclient.util.URIUtil
    URIUtil.encodeQuery(input);

OR if you want to escape chars within URI

public static String escapeURIPathParam(String input) {
  StringBuilder resultStr = new StringBuilder();
  for (char ch : input.toCharArray()) {
   if (isUnsafe(ch)) {
    resultStr.append('%');
    resultStr.append(toHex(ch / 16));
    resultStr.append(toHex(ch % 16));
   } else{
    resultStr.append(ch);
   }
  }
  return resultStr.toString();
 }

 private static char toHex(int ch) {
  return (char) (ch < 10 ? '0' + ch : 'A' + ch - 10);
 }

 private static boolean isUnsafe(char ch) {
  if (ch > 128 || ch < 0)
   return true;
  return " %$&+,/:;=?@<>#%".indexOf(ch) >= 0;
 }

Process.start: how to get the output?

  1. It is possible to get the command line shell output of a process as described here : http://www.c-sharpcorner.com/UploadFile/edwinlima/SystemDiagnosticProcess12052005035444AM/SystemDiagnosticProcess.aspx

  2. This depends on mencoder. If it ouputs this status on the command line then yes :)

How to change root logging level programmatically for logback

Here's a controller

@RestController
@RequestMapping("/loggers")
public class LoggerConfigController {

private final static org.slf4j.Logger LOGGER = LoggerFactory.getLogger(PetController.class);

@GetMapping()
public List<LoggerDto> getAllLoggers() throws CoreException {
    
    LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
    
    List<Logger> loggers = loggerContext.getLoggerList();
    
    List<LoggerDto> loggerDtos = new ArrayList<>();
    
    for (Logger logger : loggers) {
        
        if (Objects.isNull(logger.getLevel())) {
            continue;
        }
        
        LoggerDto dto = new LoggerDto(logger.getName(), logger.getLevel().levelStr);
        loggerDtos.add(dto);
    }
    
    if (LOGGER.isDebugEnabled()) {
        LOGGER.debug("All loggers retrieved. Total of {} loggers found", loggerDtos.size());
    }
    
    return loggerDtos;
}

@PutMapping
public boolean updateLoggerLevel(
        @RequestParam String name, 
        @RequestParam String level
)throws CoreException {
    
    LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
    
    Logger logger = loggerContext.getLogger(name);
    
    if (Objects.nonNull(logger) && StringUtils.isNotBlank(level)) {
        
        switch (level) {
            case "INFO":
                logger.setLevel(Level.INFO);
                LOGGER.info("Logger [{}] updated to [{}]", name, level);
                break;
                
            case "DEBUG":
                logger.setLevel(Level.DEBUG);
                LOGGER.info("Logger [{}] updated to [{}]", name, level);
                break;
                
            case "ALL":
                logger.setLevel(Level.ALL);
                LOGGER.info("Logger [{}] updated to [{}]", name, level);
                break;
                
            case "OFF":
            default: 
                logger.setLevel(Level.OFF);
                LOGGER.info("Logger [{}] updated to [{}]", name, level);
        }
    }
    
    return true;
}

}

URL encoding in Android

you can use below methods

public static String parseUrl(String surl) throws Exception
{
    URL u = new URL(surl);
    return new URI(u.getProtocol(), u.getAuthority(), u.getPath(), u.getQuery(), u.getRef()).toString();
}

or

public String parseURL(String url, Map<String, String> params)
{
    Builder builder = Uri.parse(url).buildUpon();
    for (String key : params.keySet())
    {
        builder.appendQueryParameter(key, params.get(key));
    }
    return builder.build().toString();
}

the second one is better than first.

How should I escape strings in JSON?

I think the best answer in 2017 is to use the javax.json APIs. Use javax.json.JsonBuilderFactory to create your json objects, then write the objects out using javax.json.JsonWriterFactory. Very nice builder/writer combination.

QR Code encoding and decoding using zxing

I tried using ISO-8859-1 as said in the first answer. All went ok on encoding, but when I tried to get the byte[] using result string on decoding, all negative bytes became the character 63 (question mark). The following code does not work:

// Encoding works great
byte[] contents = new byte[]{-1};
QRCodeWriter codeWriter = new QRCodeWriter();
BitMatrix bitMatrix = codeWriter.encode(new String(contents, Charset.forName("ISO-8859-1")), BarcodeFormat.QR_CODE, w, h);

// Decodes like this fails
LuminanceSource ls = new BufferedImageLuminanceSource(encodedBufferedImage);
Result result = new QRCodeReader().decode(new BinaryBitmap( new HybridBinarizer(ls)));
byte[] resultBytes = result.getText().getBytes(Charset.forName("ISO-8859-1")); // a byte[] with byte 63 is given
return resultBytes;

It looks so strange because the API in a very old version (don't know exactly) had a method thar works well:

Vector byteSegments = result.getByteSegments();

So I tried to search why this method was removed and realized that there is a way to get ByteSegments, through metadata. So my decode method looks like:

// Decodes like this works perfectly
LuminanceSource ls = new BufferedImageLuminanceSource(encodedBufferedImage);
Result result = new QRCodeReader().decode(new BinaryBitmap( new HybridBinarizer(ls)));
Vector byteSegments = (Vector) result.getResultMetadata().get(ResultMetadataType.BYTE_SEGMENTS);  
int i = 0;
int tam = 0;
for (Object o : byteSegments) {
    byte[] bs = (byte[])o;
    tam += bs.length;
}
byte[] resultBytes = new byte[tam];
i = 0;
for (Object o : byteSegments) {
    byte[] bs = (byte[])o;
    for (byte b : bs) {
        resultBytes[i++] = b;
    }
}
return resultBytes;

How to store custom objects in NSUserDefaults

I create a library RMMapper (https://github.com/roomorama/RMMapper) to help save custom object into NSUserDefaults easier and more convenient, because implementing encodeWithCoder and initWithCoder is super boring!

To mark a class as archivable, just use: #import "NSObject+RMArchivable.h"

To save a custom object into NSUserDefaults:

#import "NSUserDefaults+RMSaveCustomObject.h"
NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];
[defaults rm_setCustomObject:user forKey:@"SAVED_DATA"];

To get custom obj from NSUserDefaults:

user = [defaults rm_customObjectForKey:@"SAVED_DATA"]; 

Java: how to use UrlConnection to post request with authorization?

A fine example found here. Powerlord got it right, below, for POST you need HttpURLConnection, instead.

Below is the code to do that,

    URL url = new URL(urlString);
    URLConnection conn = url.openConnection();
    conn.setDoOutput(true);
    conn.setRequestProperty ("Authorization", encodedCredentials);

    OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());

    writer.write(data);
    writer.flush();
    String line;
    BufferedReader reader = new BufferedReader(new 
                                     InputStreamReader(conn.getInputStream()));
    while ((line = reader.readLine()) != null) {
      System.out.println(line);
    }
    writer.close();
    reader.close();

Change URLConnection to HttpURLConnection, to make it POST request.

    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
    conn.setRequestMethod("POST");

Suggestion (...in comments):

You might need to set these properties too,

conn.setRequestProperty( "Content-type", "application/x-www-form-urlencoded");
conn.setRequestProperty( "Accept", "*/*" );

c# Image resizing to different size while preserving aspect ratio

I'm going to add my code here too. This code will allow you resize an image with or without the aspect ratio being enforced or to resize with padding. This is a modified version of egrunin's code.

using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.IO;

namespace ConsoleApplication1
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var path = Directory.GetParent(Directory.GetCurrentDirectory()).Parent.FullName;
            ResizeImage(path, "large.jpg", path, "new.jpg", 100, 100, true, true);
        }

        /// <summary>Resizes an image to a new width and height.</summary>
        /// <param name="originalPath">The folder which holds the original image.</param>
        /// <param name="originalFileName">The file name of the original image.</param>
        /// <param name="newPath">The folder which will hold the resized image.</param>
        /// <param name="newFileName">The file name of the resized image.</param>
        /// <param name="maximumWidth">When resizing the image, this is the maximum width to resize the image to.</param>
        /// <param name="maximumHeight">When resizing the image, this is the maximum height to resize the image to.</param>
        /// <param name="enforceRatio">Indicates whether to keep the width/height ratio aspect or not. If set to false, images with an unequal width and height will be distorted and padding is disregarded. If set to true, the width/height ratio aspect is maintained and distortion does not occur.</param>
        /// <param name="addPadding">Indicates whether fill the smaller dimension of the image with a white background. If set to true, the white padding fills the smaller dimension until it reach the specified max width or height. This is used for maintaining a 1:1 ratio if the max width and height are the same.</param>
        private static void ResizeImage(string originalPath, string originalFileName, string newPath, string newFileName, int maximumWidth, int maximumHeight, bool enforceRatio, bool addPadding)
        {
            var image = Image.FromFile(originalPath + "\\" + originalFileName);
            var imageEncoders = ImageCodecInfo.GetImageEncoders();
            EncoderParameters encoderParameters = new EncoderParameters(1);
            encoderParameters.Param[0] = new EncoderParameter(Encoder.Quality, 100L);
            var canvasWidth = maximumWidth;
            var canvasHeight = maximumHeight;
            var newImageWidth = maximumWidth;
            var newImageHeight = maximumHeight;
            var xPosition = 0;
            var yPosition = 0;


            if (enforceRatio)
            {
                var ratioX = maximumWidth / (double)image.Width;
                var ratioY = maximumHeight / (double)image.Height;
                var ratio = ratioX < ratioY ? ratioX : ratioY;
                newImageHeight = (int)(image.Height * ratio);
                newImageWidth = (int)(image.Width * ratio);

                if (addPadding)
                {
                    xPosition = (int)((maximumWidth - (image.Width * ratio)) / 2);
                    yPosition = (int)((maximumHeight - (image.Height * ratio)) / 2);
                }
                else
                {
                    canvasWidth = newImageWidth;
                    canvasHeight = newImageHeight;                  
                }
            }

            var thumbnail = new Bitmap(canvasWidth, canvasHeight);
            var graphic = Graphics.FromImage(thumbnail);

            if (enforceRatio && addPadding)
            {
                graphic.Clear(Color.White);
            }

            graphic.InterpolationMode = InterpolationMode.HighQualityBicubic;
            graphic.SmoothingMode = SmoothingMode.HighQuality;
            graphic.PixelOffsetMode = PixelOffsetMode.HighQuality;
            graphic.CompositingQuality = CompositingQuality.HighQuality;
            graphic.DrawImage(image, xPosition, yPosition, newImageWidth, newImageHeight);

            thumbnail.Save(newPath + "\\" + newFileName, imageEncoders[1], encoderParameters);
        }
    }
}

Java: Converting String to and from ByteBuffer and associated problems

Check out the CharsetEncoder and CharsetDecoder API descriptions - You should follow a specific sequence of method calls to avoid this problem. For example, for CharsetEncoder:

  1. Reset the encoder via the reset method, unless it has not been used before;
  2. Invoke the encode method zero or more times, as long as additional input may be available, passing false for the endOfInput argument and filling the input buffer and flushing the output buffer between invocations;
  3. Invoke the encode method one final time, passing true for the endOfInput argument; and then
  4. Invoke the flush method so that the encoder can flush any internal state to the output buffer.

By the way, this is the same approach I am using for NIO although some of my colleagues are converting each char directly to a byte in the knowledge they are only using ASCII, which I can imagine is probably faster.

In a URL, should spaces be encoded using %20 or +?

According to the W3C (and they are the official source on these things), a space character in the query string (and in the query string only) may be encoded as either "%20" or "+". From the section "Query strings" under "Recommendations":

Within the query string, the plus sign is reserved as shorthand notation for a space. Therefore, real plus signs must be encoded. This method was used to make query URIs easier to pass in systems which did not allow spaces.

According to section 3.4 of RFC2396 which is the official specification on URIs in general, the "query" component is URL-dependent:

3.4. Query Component The query component is a string of information to be interpreted by the resource.

   query         = *uric

Within a query component, the characters ";", "/", "?", ":", "@", "&", "=", "+", ",", and "$" are reserved.

It is therefore a bug in the other software if it does not accept URLs with spaces in the query string encoded as "+" characters.

As for the third part of your question, one way (though slightly ugly) to fix the output from URLEncoder.encode() is to then call replaceAll("\\+","%20") on the return value.

Using Python to execute a command on every file in a folder

Use os.walk to iterate recursively over directory content:

import os

root_dir = '.'

for directory, subdirectories, files in os.walk(root_dir):
    for file in files:
        print os.path.join(directory, file)

No real difference between os.system and subprocess.call here - unless you have to deal with strangely named files (filenames including spaces, quotation marks and so on). If this is the case, subprocess.call is definitely better, because you don't need to do any shell-quoting on file names. os.system is better when you need to accept any valid shell command, e.g. received from user in the configuration file.

A generic error occurred in GDI+, JPEG Image to MemoryStream

  • I had this issue on a test server but not on the live server.
  • I was writing the image to a stream, so it wasn't a permission issue.
  • I'd been directly deploying some of the .dll's to the test server.
  • Deploying the entire solution fixed the issue, so it was probably a weird compilation mismatch

How to include header files in GCC search path?

Try gcc -c -I/home/me/development/skia sample.c.

Reading a UTF8 CSV file with Python

Had the same problem on another server, but realized that locales are messed.

export LC_ALL="en_US.UTF-8"

fixed the problem

HTTP URL Address Encoding in Java

The java.net.URI class can help; in the documentation of URL you find

Note, the URI class does perform escaping of its component fields in certain circumstances. The recommended way to manage the encoding and decoding of URLs is to use an URI

Use one of the constructors with more than one argument, like:

URI uri = new URI(
    "http", 
    "search.barnesandnoble.com", 
    "/booksearch/first book.pdf",
    null);
URL url = uri.toURL();
//or String request = uri.toString();

(the single-argument constructor of URI does NOT escape illegal characters)


Only illegal characters get escaped by above code - it does NOT escape non-ASCII characters (see fatih's comment).
The toASCIIString method can be used to get a String only with US-ASCII characters:

URI uri = new URI(
    "http", 
    "search.barnesandnoble.com", 
    "/booksearch/é",
    null);
String request = uri.toASCIIString();

For an URL with a query like http://www.google.com/ig/api?weather=São Paulo, use the 5-parameter version of the constructor:

URI uri = new URI(
        "http", 
        "www.google.com", 
        "/ig/api",
        "weather=São Paulo",
        null);
String request = uri.toASCIIString();

Java equivalent to JavaScript's encodeURIComponent that produces identical output?

Looking at the implementation differences, I see that:

MDC on encodeURIComponent():

  • literal characters (regex representation): [-a-zA-Z0-9._*~'()!]

Java 1.5.0 documentation on URLEncoder:

  • literal characters (regex representation): [-a-zA-Z0-9._*]
  • the space character " " is converted into a plus sign "+".

So basically, to get the desired result, use URLEncoder.encode(s, "UTF-8") and then do some post-processing:

  • replace all occurrences of "+" with "%20"
  • replace all occurrences of "%xx" representing any of [~'()!] back to their literal counter-parts

Java - Convert String to valid URI object

If you don't like libraries, how about this?

Note that you should not use this function on the whole URL, instead you should use this on the components...e.g. just the "a b" component, as you build up the URL - otherwise the computer won't know what characters are supposed to have a special meaning and which ones are supposed to have a literal meaning.

/** Converts a string into something you can safely insert into a URL. */
public static String encodeURIcomponent(String s)
{
    StringBuilder o = new StringBuilder();
    for (char ch : s.toCharArray()) {
        if (isUnsafe(ch)) {
            o.append('%');
            o.append(toHex(ch / 16));
            o.append(toHex(ch % 16));
        }
        else o.append(ch);
    }
    return o.toString();
}

private static char toHex(int ch)
{
    return (char)(ch < 10 ? '0' + ch : 'A' + ch - 10);
}

private static boolean isUnsafe(char ch)
{
    if (ch > 128 || ch < 0)
        return true;
    return " %$&+,/:;=?@<>#%".indexOf(ch) >= 0;
}

How to Count Duplicates in List with LINQ

The other solutions use GroupBy. GroupBy is slow (it holds all the elements in memory) so I wrote my own method CountBy:

public static Dictionary<TKey,int> CountBy<TSource,TKey>(this IEnumerable<TSource> source, Func<TSource,TKey> keySelector)
{
    var countsByKey = new Dictionary<TKey,int>();
    foreach(var x in source)
    {
        var key = keySelector(x);
        if (!countsByKey.ContainsKey(key))
            countsByKey[key] = 0;
        countsByKey[key] += 1;
    }
    return countsByKey;
}

How do I encode URI parameter values?

It seems that CharEscapers from Google GData-java-client has what you want. It has uriPathEscaper method, uriQueryStringEscaper, and generic uriEscaper. (All return Escaper object which does actual escaping). Apache License.

java.net.URLEncoder.encode(String) is deprecated, what should I use instead?

Use the other encode method in URLEncoder:

URLEncoder.encode(String, String)

The first parameter is the text to encode; the second is the name of the character encoding to use (e.g., UTF-8). For example:

System.out.println(
  URLEncoder.encode(
    "urlParameterString",
    java.nio.charset.StandardCharsets.UTF_8.toString()
  )
);

How do I use 3DES encryption/decryption in Java?

I had hard times figuring it out myself and this post helped me to find the right answer for my case. When working with financial messaging as ISO-8583 the 3DES requirements are quite specific, so for my especial case the "DESede/CBC/PKCS5Padding" combinations wasn't solving the problem. After some comparative testing of my results against some 3DES calculators designed for the financial world I found the the value "DESede/ECB/Nopadding" is more suited for the the specific task.

Here is a demo implementation of my TripleDes class (using the Bouncy Castle provider)



    import java.security.InvalidKeyException;
    import java.security.NoSuchAlgorithmException;
    import java.security.NoSuchProviderException;
    import java.security.Security;
    import javax.crypto.BadPaddingException;
    import javax.crypto.Cipher;
    import javax.crypto.IllegalBlockSizeException;
    import javax.crypto.NoSuchPaddingException;
    import javax.crypto.SecretKey;
    import javax.crypto.spec.SecretKeySpec;
    import org.bouncycastle.jce.provider.BouncyCastleProvider;


    /**
     *
     * @author Jose Luis Montes de Oca
     */
    public class TripleDesCipher {
       private static String TRIPLE_DES_TRANSFORMATION = "DESede/ECB/Nopadding";
       private static String ALGORITHM = "DESede";
       private static String BOUNCY_CASTLE_PROVIDER = "BC";
       private Cipher encrypter;
       private Cipher decrypter;

       public TripleDesCipher(byte[] key) throws NoSuchAlgorithmException, NoSuchProviderException, NoSuchPaddingException,
             InvalidKeyException {
          Security.addProvider(new BouncyCastleProvider());
          SecretKey keySpec = new SecretKeySpec(key, ALGORITHM);
          encrypter = Cipher.getInstance(TRIPLE_DES_TRANSFORMATION, BOUNCY_CASTLE_PROVIDER);
          encrypter.init(Cipher.ENCRYPT_MODE, keySpec);
          decrypter = Cipher.getInstance(TRIPLE_DES_TRANSFORMATION, BOUNCY_CASTLE_PROVIDER);
          decrypter.init(Cipher.DECRYPT_MODE, keySpec);
       }

       public byte[] encode(byte[] input) throws IllegalBlockSizeException, BadPaddingException {
          return encrypter.doFinal(input);
       }

       public byte[] decode(byte[] input) throws IllegalBlockSizeException, BadPaddingException {
          return decrypter.doFinal(input);
       }
    }

SELECT with a Replace()

You can reference is that way if you wrap the query, like this:

SELECT P
FROM (SELECT Replace(Postcode, ' ', '') AS P
      FROM Contacts) innertable
WHERE P LIKE 'NW101%'

Be sure to give the wrapped select an alias, even unused (SQL Server doesn't allow it without one IIRC)

How do I use a regex in a shell script?

To complement the existing helpful answers:

Using Bash's own regex-matching operator, =~, is a faster alternative in this case, given that you're only matching a single value already stored in a variable:

set -- '12-34-5678' # set $1 to sample value

kREGEX_DATE='^[0-9]{2}[-/][0-9]{2}[-/][0-9]{4}$' # note use of [0-9] to avoid \d
[[ $1 =~ $kREGEX_DATE ]]
echo $? # 0 with the sample value, i.e., a successful match

Note, however, that the caveat re using flavor-specific regex constructs such as \d equally applies: While =~ supports EREs (extended regular expressions), it also supports the host platform's specific extension - it's a rare case of Bash's behavior being platform-dependent.

To remain portable (in the context of Bash), stick to the POSIX ERE specification.

Note that =~ even allows you to define capture groups (parenthesized subexpressions) whose matches you can later access through Bash's special ${BASH_REMATCH[@]} array variable.

Further notes:

  • $kREGEX_DATE is used unquoted, which is necessary for the regex to be recognized as such (quoted parts would be treated as literals).

  • While not always necessary, it is advisable to store the regex in a variable first, because Bash has trouble with regex literals containing \.

    • E.g., on Linux, where \< is supported to match word boundaries, [[ 3 =~ \<3 ]] && echo yes doesn't work, but re='\<3'; [[ 3 =~ $re ]] && echo yes does.
  • I've changed variable name REGEX_DATE to kREGEX_DATE (k signaling a (conceptual) constant), so as to ensure that the name isn't an all-uppercase name, because all-uppercase variable names should be avoided to prevent conflicts with special environment and shell variables.

In-place edits with sed on OS X

The -i flag probably doesn't work for you, because you followed an example for GNU sed while macOS uses BSD sed and they have a slightly different syntax.

All the other answers tell you how to correct the syntax to work with BSD sed. The alternative is to install GNU sed on your macOS with:

brew install gsed

and then use it instead of the sed version shipped with macOS (note the g prefix), e.g:

gsed -i 's/oldword/newword/' file1.txt

If you want GNU sed commands to be always portable to your macOS, you could prepend "gnubin" directory to your path, by adding something like this to your .bashrc/.zshrc file (run brew info gsed to see what exactly you need to do):

export PATH="/usr/local/opt/gnu-sed/libexec/gnubin:$PATH"

and from then on the GNU sed becomes your default sed and you can simply run:

sed -i 's/oldword/newword/' file1.txt

How do I get the Session Object in Spring?

i made my own utils. it is handy. :)

package samples.utils;

import java.util.Arrays;
import java.util.Collection;
import java.util.Locale;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import javax.sql.DataSource;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.MessageSource;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.ui.context.Theme;
import org.springframework.util.ClassUtils;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.ThemeResolver;
import org.springframework.web.servlet.support.RequestContextUtils;


/**
 * SpringMVC????
 * 
 * @author ??([email protected])
 *
 */
public final class WebContextHolder {

    private static final Logger LOGGER = LoggerFactory.getLogger(WebContextHolder.class);

    private static WebContextHolder INSTANCE = new WebContextHolder();

    public WebContextHolder get() {
        return INSTANCE;
    }

    private WebContextHolder() {
        super();
    }

    // --------------------------------------------------------------------------------------------------------------

    public HttpServletRequest getRequest() {
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.currentRequestAttributes();
        return attributes.getRequest();
    }

    public HttpSession getSession() {
        return getSession(true);
    }

    public HttpSession getSession(boolean create) {
        return getRequest().getSession(create);
    }

    public String getSessionId() {
        return getSession().getId();
    }

    public ServletContext getServletContext() {
        return getSession().getServletContext();    // servlet2.3
    }

    public Locale getLocale() {
        return RequestContextUtils.getLocale(getRequest());
    }

    public Theme getTheme() {
        return RequestContextUtils.getTheme(getRequest());
    }

    public ApplicationContext getApplicationContext() {
        return WebApplicationContextUtils.getWebApplicationContext(getServletContext());
    }

    public ApplicationEventPublisher getApplicationEventPublisher() {
        return (ApplicationEventPublisher) getApplicationContext();
    }

    public LocaleResolver getLocaleResolver() {
        return RequestContextUtils.getLocaleResolver(getRequest());
    }

    public ThemeResolver getThemeResolver() {
        return RequestContextUtils.getThemeResolver(getRequest());
    }

    public ResourceLoader getResourceLoader() {
        return (ResourceLoader) getApplicationContext();
    }

    public ResourcePatternResolver getResourcePatternResolver() {
        return (ResourcePatternResolver) getApplicationContext();
    }

    public MessageSource getMessageSource() {
        return (MessageSource) getApplicationContext();
    }

    public ConversionService getConversionService() {
        return getBeanFromApplicationContext(ConversionService.class);
    }

    public DataSource getDataSource() {
        return getBeanFromApplicationContext(DataSource.class);
    }

    public Collection<String> getActiveProfiles() {
        return Arrays.asList(getApplicationContext().getEnvironment().getActiveProfiles());
    }

    public ClassLoader getBeanClassLoader() {
        return ClassUtils.getDefaultClassLoader();
    }

    private <T> T getBeanFromApplicationContext(Class<T> requiredType) {
        try {
            return getApplicationContext().getBean(requiredType);
        } catch (NoUniqueBeanDefinitionException e) {
            LOGGER.error(e.getMessage(), e);
            throw e;
        } catch (NoSuchBeanDefinitionException e) {
            LOGGER.warn(e.getMessage());
            return null;
        }
    }

}

ADB Install Fails With INSTALL_FAILED_TEST_ONLY

Add -t install flag, as on the screenshot below:

answer is in the red box

Linux shell sort file according to the second column?

To sort by second field only (thus where second fields match, those lines with matches remain in the order they are in the original without sorting on other fields) :

sort -k 2,2 -s orig_file > sorted_file

Are there such things as variables within an Excel formula?

Now you can use the function LET to declare variables within Excel formulas. This function is available since Jun 2020 for Microsoft 365 users.

Given your example, the formula will be:

=LET(MyFunc,VLOOKUP(A1,B:B,1,0), IF(MyFunc > 10, MyFunc - 10, MyFunc ) )

The 1st argument is the variable name and the 2nd argument is the function or range. You can add more pairs of arguments variable, function/range.

After adding the variables, the last argument will be your formula of interest -- calling the variables you just created.

For more information, please access the Microsoft webpage here.

Different ways of loading a file as an InputStream

There are subtle differences as to how the fileName you are passing is interpreted. Basically, you have 2 different methods: ClassLoader.getResourceAsStream() and Class.getResourceAsStream(). These two methods will locate the resource differently.

In Class.getResourceAsStream(path), the path is interpreted as a path local to the package of the class you are calling it from. For example calling, String.class.getResourceAsStream("myfile.txt") will look for a file in your classpath at the following location: "java/lang/myfile.txt". If your path starts with a /, then it will be considered an absolute path, and will start searching from the root of the classpath. So calling String.class.getResourceAsStream("/myfile.txt") will look at the following location in your class path ./myfile.txt.

ClassLoader.getResourceAsStream(path) will consider all paths to be absolute paths. So calling String.class.getClassLoader().getResourceAsStream("myfile.txt") and String.class.getClassLoader().getResourceAsStream("/myfile.txt") will both look for a file in your classpath at the following location: ./myfile.txt.

Everytime I mention a location in this post, it could be a location in your filesystem itself, or inside the corresponding jar file, depending on the Class and/or ClassLoader you are loading the resource from.

In your case, you are loading the class from an Application Server, so your should use Thread.currentThread().getContextClassLoader().getResourceAsStream(fileName) instead of this.getClass().getClassLoader().getResourceAsStream(fileName). this.getClass().getResourceAsStream() will also work.

Read this article for more detailed information about that particular problem.


Warning for users of Tomcat 7 and below

One of the answers to this question states that my explanation seems to be incorrect for Tomcat 7. I've tried to look around to see why that would be the case.

So I've looked at the source code of Tomcat's WebAppClassLoader for several versions of Tomcat. The implementation of findResource(String name) (which is utimately responsible for producing the URL to the requested resource) is virtually identical in Tomcat 6 and Tomcat 7, but is different in Tomcat 8.

In versions 6 and 7, the implementation does not attempt to normalize the resource name. This means that in these versions, classLoader.getResourceAsStream("/resource.txt") may not produce the same result as classLoader.getResourceAsStream("resource.txt") event though it should (since that what the Javadoc specifies). [source code]

In version 8 though, the resource name is normalized to guarantee that the absolute version of the resource name is the one that is used. Therefore, in Tomcat 8, the two calls described above should always return the same result. [source code]

As a result, you have to be extra careful when using ClassLoader.getResourceAsStream() or Class.getResourceAsStream() on Tomcat versions earlier than 8. And you must also keep in mind that class.getResourceAsStream("/resource.txt") actually calls classLoader.getResourceAsStream("resource.txt") (the leading / is stripped).

How to solve Object reference not set to an instance of an object.?

I think you just need;

List<string> list = new List<string>();
list.Add("hai");

There is a difference between

List<string> list; 

and

List<string> list = new List<string>();

When you didn't use new keyword in this case, your list didn't initialized. And when you try to add it hai, obviously you get an error.

How to do multiple arguments to map function where one remains the same in python?

In :nums = [1, 2, 3]

In :map(add, nums, [2]*len(nums))

Out:[3, 4, 5]

How to check if object property exists with a variable holding the property name?

A much more secure way to check if property exists on the object is to use empty object or object prototype to call hasOwnProperty()

var foo = {
  hasOwnProperty: function() {
    return false;
  },
  bar: 'Here be dragons'
};

foo.hasOwnProperty('bar'); // always returns false

// Use another Object's hasOwnProperty and call it with 'this' set to foo
({}).hasOwnProperty.call(foo, 'bar'); // true

// It's also possible to use the hasOwnProperty property from the Object
// prototype for this purpose
Object.prototype.hasOwnProperty.call(foo, 'bar'); // true

Reference from MDN Web Docs - Object.prototype.hasOwnProperty()

How to retrieve field names from temporary table (SQL Server 2008)

select * 
from tempdb.INFORMATION_SCHEMA.COLUMNS
where table_name like '#MyTempTable%'

curl: (6) Could not resolve host: application

In my case, I copied the curl command from Confluence to TextEdit. After spending almost an hour, and trying to paste the command in different text editors in order to sanitize, finally, PyCharm helped me (IntelliJ should help too)

After pasting it in PyCharm I got to see the error

Non-breaking spaces

After removing these "NBSP" (non-breaking spaces), the command started running fine.

jQuery $.ajax(), pass success data into separate function

In the first code block, you're never using the str parameter. Did you mean to say the following?

testFunc = function(str, callback) {
    $.ajax({
        type: 'POST',
        url: 'http://www.myurl.com',
        data: str,
        success: callback
    });
}

Determine the path of the executing BASH script

Contributed by Stephane CHAZELAS on c.u.s. Assuming POSIX shell:

prg=$0
if [ ! -e "$prg" ]; then
  case $prg in
    (*/*) exit 1;;
    (*) prg=$(command -v -- "$prg") || exit;;
  esac
fi
dir=$(
  cd -P -- "$(dirname -- "$prg")" && pwd -P
) || exit
prg=$dir/$(basename -- "$prg") || exit 

printf '%s\n' "$prg"

Git push error pre-receive hook declined

Following resolved problem in my local machine:

A. First, ensure that you are using the correct log on details to connect to Bitbucket Server (ie. a username/password/SSH key that belongs to you) 

B. Then, ensure that the name/email address is correctly set in your local Git configuration: Set your local Git configuration for the account that you are trying to push under (the check asserts that you are the person who committed the files) * Note that this is case sensitive, both for name and email address * It is also space sensitive - some company accounts have extra spaces/characters in their name eg. "Contractor/ space space(LDN)".  You must include the same number of spaces in your configuration as on Bitbucket Server.  Check this in Notepad if stuck.

C. If you were using the wrong account, simply switch your account credentials (username/password/SSH key) and try pushing again.

D. Else, if your local configuration incorrect you will need to amend it

For MAC

open -a TextEdit.app ~/.gitconfig

NOTE: You will have to fix up the old commits that you were trying to push.

  1. Amend your last commit:

    > git commit --amend --reset-author
    
      
    <save and quit the commit file text editor that opens, if Vim then
    :wq to save and quit>
    
  2. Try re-pushing your commits:

    > git push
    

PKIX path building failed in Java application

In my case the issue was resolved by installing Oracle's official JDK 10 as opposed to using the default OpenJDK that came with my Ubuntu. This is the guide I followed: https://www.linuxuprising.com/2018/04/install-oracle-java-10-in-ubuntu-or.html

Clear screen in shell

In addition to being an all-around great CLI library, click also provides a platform-agnostic clear() function:

import click
click.clear()

Python object.__repr__(self) should be an expression?

"but does that mean it should just be an example of the sort of expression you could use, or should it be an actual expression, that can be executed (eval etc..) to recreate the object? Or... should it be just a rehasing of the actual expression which was used, for pure information purposes?"

Wow, that's a lot of hand-wringing.

  1. An "an example of the sort of expression you could use" would not be a representation of a specific object. That can't be useful or meaningful.

  2. What is the difference between "an actual expression, that can ... recreate the object" and "a rehasing of the actual expression which was used [to create the object]"? Both are an expression that creates the object. There's no practical distinction between these. A repr call could produce either a new expression or the original expression. In many cases, they're the same.

Note that this isn't always possible, practical or desirable.

In some cases, you'll notice that repr() presents a string which is clearly not an expression of any kind. The default repr() for any class you define isn't useful as an expression.

In some cases, you might have mutual (or circular) references between objects. The repr() of that tangled hierarchy can't make sense.

In many cases, an object is built incrementally via a parser. For example, from XML or JSON or something. What would the repr be? The original XML or JSON? Clearly not, since they're not Python. It could be some Python expression that generated the XML. However, for a gigantic XML document, it might not be possible to write a single Python expression that was the functional equivalent of parsing XML.

How to sort an associative array by its values in Javascript?

Javascript doesn't have "associative arrays" the way you're thinking of them. Instead, you simply have the ability to set object properties using array-like syntax (as in your example), plus the ability to iterate over an object's properties.

The upshot of this is that there is no guarantee as to the order in which you iterate over the properties, so there is nothing like a sort for them. Instead, you'll need to convert your object properties into a "true" array (which does guarantee order). Here's a code snippet for converting an object into an array of two-tuples (two-element arrays), sorting it as you describe, then iterating over it:

var tuples = [];

for (var key in obj) tuples.push([key, obj[key]]);

tuples.sort(function(a, b) {
    a = a[1];
    b = b[1];

    return a < b ? -1 : (a > b ? 1 : 0);
});

for (var i = 0; i < tuples.length; i++) {
    var key = tuples[i][0];
    var value = tuples[i][1];

    // do something with key and value
}

You may find it more natural to wrap this in a function which takes a callback:

_x000D_
_x000D_
function bySortedValue(obj, callback, context) {_x000D_
  var tuples = [];_x000D_
_x000D_
  for (var key in obj) tuples.push([key, obj[key]]);_x000D_
_x000D_
  tuples.sort(function(a, b) {_x000D_
    return a[1] < b[1] ? 1 : a[1] > b[1] ? -1 : 0_x000D_
  });_x000D_
_x000D_
  var length = tuples.length;_x000D_
  while (length--) callback.call(context, tuples[length][0], tuples[length][1]);_x000D_
}_x000D_
_x000D_
bySortedValue({_x000D_
  foo: 1,_x000D_
  bar: 7,_x000D_
  baz: 3_x000D_
}, function(key, value) {_x000D_
  document.getElementById('res').innerHTML += `${key}: ${value}<br>`_x000D_
});
_x000D_
<p id='res'>Result:<br/><br/><p>
_x000D_
_x000D_
_x000D_

How to get JavaScript variable value in PHP

You might want to start by learning what Javascript and php are. Javascript is a client side script language running in the browser of the machine of the client connected to the webserver on which php runs. These languages can not communicate directly.

Depending on your goal you'll need to issue an AJAX get or post request to the server and return a json/xml/html/whatever response you need and inject the result back in the DOM structure of the site. I suggest Jquery, BackboneJS or any other JS framework for this. See the Jquery documentation for examples.

If you have to pass php data to JS on the same site you can echo the data as JS and turn your php data using json_encode() into JS.

<script type="text/javascript>
    var foo = <?php echo json_encode($somePhpVar); ?>
</script>

"starting Tomcat server 7 at localhost has encountered a prob"

In Servers view double-click on Tomcat and change HTTP port in Ports section to something else. Or in Package Explorer navigate to Servers Tomcat and change Connector port part inside server.xml file.

How to perform runtime type checking in Dart?

Just to clarify a bit the difference between is and runtimeType. As someone said already (and this was tested with Dart V2+) the following code:

class Foo { 
  Type get runtimeType => String;
}
main() {
  var foo = new Foo();
  if (foo is Foo) {
    print("it's a foo!");
  }
  print("type is ${foo.runtimeType}");

}

will output:

it's a foo! 
type is String

Which is wrong. Now, I can't see the reason why one should do such a thing...

Hibernate problem - "Use of @OneToMany or @ManyToMany targeting an unmapped class"

If you are using Java configuration in a spring-data-jpa project, make sure you are scanning the package that the entity is in. For example, if the entity lived com.foo.myservice.things then the following configuration annotation below would not pick it up.

You could fix it by loosening it up to just com.foo.myservice (of course, keep in mind any other effects of broadening your scope to scan for entities).

@Configuration
@EnableJpaAuditing
@EnableJpaRepositories("com.foo.myservice.repositories")
public class RepositoryConfiguration {
}

BAT file to open CMD in current directory

Create a file named open_dos_here.cmd with the following lines:

%~d1
cd "%~p1"
call cmd

Put this file at any folder. Then, go to your Send To folder (Win+E; Alt+D;shell:sendto;Enter). Create a shortcut to point to this open_dos_here.cmd

Then, in any folder, select any file or sub-folder. Right-click and select "Send To" and then select open_dos_here.cmd to open the DOS in that folder.

Closing Application with Exit button

You cannot exit your application. Using android.finish() won't exit the application, it just kills the activity. It's used when we don't want to see the previous activity on back button click. The application automatically exits when you switch off the device. The Android architecture does not support exiting the app. If you want, you can forcefully exit the app, but that's not considered good practice.

How to change the height of a div dynamically based on another div using css?

By specifying the positions we can achieve this,

.div1 {
  width:300px;
  height: auto;
  background-color: grey;  
  border:1px solid;
  position:relative;
  overflow:auto;
}
.div2 {
  width:150px;
  height:auto;
  background-color: #F4A460;  
  float:left;
}
.div3 {
  width:150px;
  height:100%;
  position:absolute;
  right:0px;
  background-color: #FFFFE0;  
  float:right;
}

but it is not possible to achieve this using float.

How to call an element in a numpy array?

Use numpy. array. flatten() to convert a 2D NumPy array into a 1D array print(array_2d) array_1d = array_2d. flatten() flatten array_2d print(array_1d)

what is the use of annotations @Id and @GeneratedValue(strategy = GenerationType.IDENTITY)? Why the generationtype is identity?

Let me answer this question:
First of all, using annotations as our configure method is just a convenient method instead of coping the endless XML configuration file.

The @Idannotation is inherited from javax.persistence.Id, indicating the member field below is the primary key of current entity. Hence your Hibernate and spring framework as well as you can do some reflect works based on this annotation. for details please check javadoc for Id

The @GeneratedValue annotation is to configure the way of increment of the specified column(field). For example when using Mysql, you may specify auto_increment in the definition of table to make it self-incremental, and then use

@GeneratedValue(strategy = GenerationType.IDENTITY)

in the Java code to denote that you also acknowledged to use this database server side strategy. Also, you may change the value in this annotation to fit different requirements.

1. Define Sequence in database

For instance, Oracle has to use sequence as increment method, say we create a sequence in Oracle:

create sequence oracle_seq;

2. Refer the database sequence

Now that we have the sequence in database, but we need to establish the relation between Java and DB, by using @SequenceGenerator:

@SequenceGenerator(name="seq",sequenceName="oracle_seq")

sequenceName is the real name of a sequence in Oracle, name is what you want to call it in Java. You need to specify sequenceName if it is different from name, otherwise just use name. I usually ignore sequenceName to save my time.

3. Use sequence in Java

Finally, it is time to make use this sequence in Java. Just add @GeneratedValue:

@GeneratedValue(strategy=GenerationType.SEQUENCE, generator="seq")

The generator field refers to which sequence generator you want to use. Notice it is not the real sequence name in DB, but the name you specified in name field of SequenceGenerator.

4. Complete

So the complete version should be like this:

public class MyTable
{
    @Id
    @SequenceGenerator(name="seq",sequenceName="oracle_seq")        
    @GeneratedValue(strategy=GenerationType.SEQUENCE, generator="seq")               
    private Integer pid;
}

Now start using these annotations to make your JavaWeb development easier.

JQuery add class to parent element

Specify the optional selector to target what you want:

jQuery(this).parent('li').addClass('yourClass');

Or:

jQuery(this).parents('li').addClass('yourClass');

Measure execution time for a Java method

Check this: System.currentTimeMillis.

With this you can calculate the time of your method by doing:

long start = System.currentTimeMillis();
class.method();
long time = System.currentTimeMillis() - start;

Add default value of datetime field in SQL Server to a timestamp

This also works:

CREATE TABLE Example(
...
created datetime default GETDATE()
);

Or:

ALTER TABLE EXAMPLE ADD created datetime default GETDATE();

Error: could not find function ... in R

You may be able to fix this error by name spacing :: the function call

comparison.cloud(colors = c("red", "green"), max.words = 100)

to

wordcloud::comparison.cloud(colors = c("red", "green"), max.words = 100)

Gradle - Could not target platform: 'Java SE 8' using tool chain: 'JDK 7 (1.7)'

Although this question specifically asks about IntelliJ, this was the first result I received on Google, so I believe that many Eclipse users may have the same problem using Buildship.

You can set your Gradle JVM in Eclipse by going to Gradle Tasks (in the default view, down at the bottom near the console), right-clicking on the specific task you are trying to run, clicking "Open Gradle Run Configuration..." and moving to the Java Home tab and picking the correct JVM for your project.

How to set time zone of a java.util.Date?

tl;dr

…parsed … from a String … time zone is not specified … I want to set a specific time zone

LocalDateTime.parse( "2018-01-23T01:23:45.123456789" )  // Parse string, lacking an offset-from-UTC and lacking a time zone, as a `LocalDateTime`.
    .atZone( ZoneId.of( "Africa/Tunis" ) )              // Assign the time zone for which you are certain this date-time was intended. Instantiates a `ZonedDateTime` object.

No Time Zone in j.u.Date

As the other correct answers stated, a java.util.Date has no time zone. It represents UTC/GMT (no time zone offset). Very confusing because its toString method applies the JVM's default time zone when generating a String representation.

Avoid j.u.Date

For this and many other reasons, you should avoid using the built-in java.util.Date & .Calendar & java.text.SimpleDateFormat. They are notoriously troublesome.

Instead use the java.time package bundled with Java 8.

java.time

The java.time classes can represent a moment on the timeline in three ways:

  • UTC (Instant)
  • With an offset (OffsetDateTime with ZoneOffset)
  • With a time zone (ZonedDateTime with ZoneId)

Instant

In java.time, the basic building block is Instant, a moment on the time line in UTC. Use Instant objects for much of your business logic.

Instant instant = Instant.now();

OffsetDateTime

Apply an offset-from-UTC to adjust into some locality’s wall-clock time.

Apply a ZoneOffset to get an OffsetDateTime.

ZoneOffset zoneOffset = ZoneOffset.of( "-04:00" );
OffsetDateTime odt = OffsetDateTime.ofInstant( instant , zoneOffset );

ZonedDateTime

Better is to apply a time zone, an offset plus the rules for handling anomalies such as Daylight Saving Time (DST).

Apply a ZoneId to an Instant to get a ZonedDateTime. Always specify a proper time zone name. Never use 3-4 abbreviations such as EST or IST that are neither unique nor standardized.

ZoneId zoneId = ZoneId.of( "America/Montreal" );
ZonedDateTime zdt = ZonedDateTime.ofInstant( instant , zoneId );

LocalDateTime

If the input string lacked any indicator of offset or zone, parse as a LocalDateTime.

If you are certain of the intended time zone, assign a ZoneId to produce a ZonedDateTime. See code example above in tl;dr section at top.

Formatted Strings

Call the toString method on any of these three classes to generate a String representing the date-time value in standard ISO 8601 format. The ZonedDateTime class extends standard format by appending the name of the time zone in brackets.

String outputInstant = instant.toString(); // Ex: 2011-12-03T10:15:30Z
String outputOdt = odt.toString(); // Ex: 2007-12-03T10:15:30+01:00
String outputZdt = zdt.toString(); // Ex: 2007-12-03T10:15:30+01:00[Europe/Paris]

For other formats use the DateTimeFormatter class. Generally best to let that class generate localized formats using the user’s expected human language and cultural norms. Or you can specify a particular format.


Table of all date-time types in Java, both modern and legacy


About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes. Hibernate 5 & JPA 2.2 support java.time.

Where to obtain the java.time classes?


Joda-Time

While Joda-Time is still actively maintained, its makers have told us to migrate to java.time as soon as is convenient. I leave this section intact as a reference, but I suggest using the java.time section above instead.

In Joda-Time, a date-time object (DateTime) truly does know its assigned time zone. That means an offset from UTC and the rules and history of that time zone’s Daylight Saving Time (DST) and other such anomalies.

String input = "2014-01-02T03:04:05";
DateTimeZone timeZone = DateTimeZone.forID( "Asia/Kolkata" );
DateTime dateTimeIndia = new DateTime( input, timeZone );
DateTime dateTimeUtcGmt = dateTimeIndia.withZone( DateTimeZone.UTC );

Call the toString method to generate a String in ISO 8601 format.

String output = dateTimeIndia.toString();

Joda-Time also offers rich capabilities for generating all kinds of other String formats.

If required, you can convert from Joda-Time DateTime to a java.util.Date.

Java.util.Date date = dateTimeIndia.toDate();

Search StackOverflow for "joda date" to find many more examples, some quite detailed.


Actually there is a time zone embedded in a java.util.Date, used for some internal functions (see comments on this Answer). But this internal time zone is not exposed as a property, and cannot be set. This internal time zone is not the one used by the toString method in generating a string representation of the date-time value; instead the JVM’s current default time zone is applied on-the-fly. So, as shorthand, we often say “j.u.Date has no time zone”. Confusing? Yes. Yet another reason to avoid these tired old classes.

Invalid use side-effecting operator Insert within a function

There is an exception (I'm using SQL 2014) when you are only using Insert/Update/Delete on Declared-Tables. These Insert/Update/Delete statements cannot contain an OUTPUT statement. The other restriction is that you are not allowed to do a MERGE, even into a Declared-Table. I broke up my Merge statements, that didn't work, into Insert/Update/Delete statements that did work.

The reason I didn't convert it to a stored-procedure is that the table-function was faster (even without the MERGE) than the stored-procedure. This is despite the stored-procedure allowing me to use Temp-Tables that have statistics. I needed the table-function to be very fast, since it is called 20-K times/day. This table function never updates the database.

I also noticed that the NewId() and RAND() SQL functions are not allowed in a function.

Is there a better way to run a command N times in bash?

The script file

bash-3.2$ cat test.sh 
#!/bin/bash

echo "The argument is  arg: $1"

for ((n=0;n<$1;n++));
do
  echo "Hi"
done

and the output below

bash-3.2$  ./test.sh 3
The argument is  arg: 3
Hi
Hi
Hi
bash-3.2$

Split pandas dataframe in two if it has more than 10 rows

def split_and_save_df(df, name, size, output_dir):
    """
    Split a df and save each chunk in a different csv file.

    Parameters:
        df : pandas df to be splitted
        name : name to give to the output file
        size : chunk size
        output_dir : directory where to write the divided df
    """
    import os
    for i in range(0, df.shape[0],size):
        start  = i
        end    = min(i+size-1, df.shape[0]) 
        subset = df.loc[start:end] 
        output_path = os.path.join(output_dir,f"{name}_{start}_{end}.csv")
        print(f"Going to write into {output_path}")
        subset.to_csv(output_path)
        output_size = os.stat(output_path).st_size
        print(f"Wrote {output_size} bytes")

ToString() function in Go

I prefer something like the following:

type StringRef []byte

func (s StringRef) String() string {
        return string(s[:])
}

…

// rather silly example, but ...
fmt.Printf("foo=%s\n",StringRef("bar"))

jquery remove "selected" attribute of option?

This works:

$("#myselect").find('option').removeAttr("selected");

or

$("#myselect").find('option:selected').removeAttr("selected");

jsFiddle

How to reference Microsoft.Office.Interop.Excel dll?

If you have VS 2013 Express and you cant find Microsoft.Office namespace, try this ('Microsoft Excel 12.0 Object Library' if you want to use Office 2007)

enter image description here

List of installed gems?

Here's a really nice one-liner to print all the Gems along with their version, homepage, and description:

Gem::Specification.sort{|a,b| a.name <=> b.name}.map {|a| puts "#{a.name} (#{a.version})"; puts "-" * 50; puts a.homepage; puts a.description; puts "\n\n"};nil

How to remove an element from the flow?

None?

I mean, other than removing it from the layout entirely with display: none, I'm pretty sure that's it.

Are you facing a particular situation in which position: absolute is not a viable solution?

How to take character input in java

use :

char ch=**scanner.nextChar**()

Hibernate JPA Sequence (non-Id)

I fixed the generation of UUID (or sequences) with Hibernate using @PrePersist annotation:

@PrePersist
public void initializeUUID() {
    if (uuid == null) {
        uuid = UUID.randomUUID().toString();
    }
}

SQL Server 2005 Using CHARINDEX() To split a string

I wouldn't exactly say it is easy or obvious, but with just two hyphens, you can reverse the string and it is not too hard:

with t as (select 'LD-23DSP-1430' as val)
select t.*,
       LEFT(val, charindex('-', val) - 1),
   SUBSTRING(val, charindex('-', val)+1, len(val) - CHARINDEX('-', reverse(val)) - charindex('-', val)),
       REVERSE(LEFT(reverse(val), charindex('-', reverse(val)) - 1))
from t;

Beyond that and you might want to use split() instead.

The meaning of NoInitialContextException error

My problem with this one was that I was creating a hibernate session, but had the JNDI settings for my database instance wrong because of a classpath problem. Just FYI...

Spring Security redirect to previous page after successful login

I've custom OAuth2 authorization and request.getHeader("Referer") is not available at poit of decision. But security request already saved in ExceptionTranslationFilter.sendStartAuthentication:

protected void sendStartAuthentication(HttpServletRequest request,...
    ...
    requestCache.saveRequest(request, response);

So, all what we need is share requestCache as Spring bean:

@Bean
public RequestCache requestCache() {
   return new HttpSessionRequestCache();
}

@Override
protected void configure(HttpSecurity http) throws Exception {
   http.authorizeRequests()
   ... 
   .requestCache().requestCache(requestCache()).and()
   ...
}     

and use it wheen authorization is finished:

@Autowired
private RequestCache requestCache;

public void authenticate(HttpServletRequest req, HttpServletResponse resp){
    ....
    SavedRequest savedRequest = requestCache.getRequest(req, resp);
    resp.sendRedirect(savedRequest != null && "GET".equals(savedRequest.getMethod()) ?  
    savedRequest.getRedirectUrl() : "defaultURL");
}

How to make inline plots in Jupyter Notebook larger?

using something like:

import matplotlib.pyplot as plt
%matplotlib inline
plt.subplots(figsize=(18,8 ))
plt.subplot(1,3,1)
plt.subplot(1,3,2)
plt.subplot(1,3,3)

The output of the command

the output of the command

How can I upload files asynchronously?

To upload file asynchronously with Jquery use below steps:

step 1 In your project open Nuget manager and add package (jquery fileupload(only you need to write it in search box it will come up and install it.)) URL: https://github.com/blueimp/jQuery-File-Upload

step 2 Add below scripts in the HTML files, which are already added to the project by running above package:

jquery.ui.widget.js

jquery.iframe-transport.js

jquery.fileupload.js

step 3 Write file upload control as per below code:

<input id="upload" name="upload" type="file" />

step 4 write a js method as uploadFile as below:

 function uploadFile(element) {
    
            $(element).fileupload({
    
                dataType: 'json',
                url: '../DocumentUpload/upload',
                autoUpload: true,
                add: function (e, data) {           
                  // write code for implementing, while selecting a file. 
                  // data represents the file data. 
                  //below code triggers the action in mvc controller
                  data.formData =
                                    {
                                     files: data.files[0]
                                    };
                  data.submit();
                },
                done: function (e, data) {          
                   // after file uploaded
                },
                progress: function (e, data) {
                    
                   // progress
                },
                fail: function (e, data) {
                    
                   //fail operation
                },
                stop: function () {
                    
                  code for cancel operation
                }
            });
        
        };

step 5 In ready function call element file upload to initiate the process as per below:

$(document).ready(function()
{
    uploadFile($('#upload'));

});

step 6 Write MVC controller and Action as per below:

public class DocumentUploadController : Controller
    {       
        
        [System.Web.Mvc.HttpPost]
        public JsonResult upload(ICollection<HttpPostedFileBase> files)
        {
            bool result = false;

            if (files != null || files.Count > 0)
            {
                try
                {
                    foreach (HttpPostedFileBase file in files)
                    {
                        if (file.ContentLength == 0)
                            throw new Exception("Zero length file!");                       
                        else 
                            //code for saving a file

                    }
                }
                catch (Exception)
                {
                    result = false;
                }
            }


            return new JsonResult()
                {
                    Data=result
                };


        }

    }

Good tutorial for using HTML5 History API (Pushstate?)

Keep in mind while using HTML5 pushstate if a user copies or bookmarks a deep link and visits it again, then that will be a direct server hit which will 404 so you need to be ready for it and even a pushstate js library won't help you. The easiest solution is to add a rewrite rule to your Nginx or Apache server like so:

Apache (in your vhost if you're using one):

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteBase /
    RewriteRule ^index\.html$ - [L]
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule . /index.html [L]
 </IfModule>

Nginx

rewrite ^(.+)$ /index.html last;

Simulate a button click in Jest

#1 Using Jest

This is how I use the Jest mock callback function to test the click event:

import React from 'react';
import { shallow } from 'enzyme';
import Button from './Button';

describe('Test Button component', () => {
  it('Test click event', () => {
    const mockCallBack = jest.fn();

    const button = shallow((<Button onClick={mockCallBack}>Ok!</Button>));
    button.find('button').simulate('click');
    expect(mockCallBack.mock.calls.length).toEqual(1);
  });
});

I am also using a module called enzyme. Enzyme is a testing utility that makes it easier to assert and select your React Components

#2 Using Sinon

Also, you can use another module called Sinon which is a standalone test spy, stubs and mocks for JavaScript. This is how it looks:

import React from 'react';
import { shallow } from 'enzyme';
import sinon from 'sinon';

import Button from './Button';

describe('Test Button component', () => {
  it('simulates click events', () => {
    const mockCallBack = sinon.spy();
    const button = shallow((<Button onClick={mockCallBack}>Ok!</Button>));

    button.find('button').simulate('click');
    expect(mockCallBack).toHaveProperty('callCount', 1);
  });
});

#3 Using Your own Spy

Finally, you can make your own naive spy (I don't recommend this approach unless you have a valid reason for that).

function MySpy() {
  this.calls = 0;
}

MySpy.prototype.fn = function () {
  return () => this.calls++;
}

it('Test Button component', () => {
  const mySpy = new MySpy();
  const mockCallBack = mySpy.fn();

  const button = shallow((<Button onClick={mockCallBack}>Ok!</Button>));

  button.find('button').simulate('click');
  expect(mySpy.calls).toEqual(1);
});

Git Remote: Error: fatal: protocol error: bad line length character: Unab

I had same problem when I did git pull

git pull fatal: protocol error: bad line length character: <htm fatal: the remote end hung up unexpectedly

I changed my remote url HTTP to SSH, and it worked for me.

git remote set-url origin "HTTP" to "SSH"

get Context in non-Activity class

If your class is non-activity class, and creating an instance of it from the activiy, you can pass an instance of context via constructor of the later as follows:

class YourNonActivityClass{

// variable to hold context
private Context context;

//save the context recievied via constructor in a local variable

public YourNonActivityClass(Context context){
    this.context=context;
}

}

You can create instance of this class from the activity as follows:

new YourNonActivityClass(this);

TypeError: a bytes-like object is required, not 'str' in python and CSV

I had the same issue with Python3. My code was writing into io.BytesIO().

Replacing with io.StringIO() solved.

Date object to Calendar [Java]

You don't need to convert to Calendar for this, you can just use getTime()/setTime() instead.

getTime(): Returns the number of milliseconds since January 1, 1970, 00:00:00 GMT represented by this Date object.

setTime(long time) : Sets this Date object to represent a point in time that is time milliseconds after January 1, 1970 00:00:00 GMT. )

There are 1000 milliseconds in a second, and 60 seconds in a minute. Just do the math.

    Date now = new Date();
    Date oneMinuteInFuture = new Date(now.getTime() + 1000L * 60);
    System.out.println(now);
    System.out.println(oneMinuteInFuture);

The L suffix in 1000 signifies that it's a long literal; these calculations usually overflows int easily.

How to prevent column break within an element?

<style>
ul li{display: table;}  
</style>

works perfectly

Laravel Eloquent - Get one Row

laravel 5.8

If you don't even need an entire row, you may extract a single value from a record using the value() method. This method will return the value of the column directly:

$first_name = DB::table('users')->where('email' ,'me@mail,com')->value('first_name');

check docs

how to get current month and year

If you have following two labels:

<asp:Label ID="MonthLabel" runat="server" />
<asp:Label ID="YearLabel" runat="server" />

Than you can use following code just need to set the Text Property for these labels like:

MonthLabel.Text = DateTime.Now.Month.ToString();
YearLabel.Text = DateTime.Now.Year.ToString();

Custom fonts and XML layouts (Android)

This might be a little late, but you need to create a singleton class that returns the custom typeface to avoid memory leaks.

TypeFace class:

public class OpenSans {

private static OpenSans instance;
private static Typeface typeface;

public static OpenSans getInstance(Context context) {
    synchronized (OpenSans.class) {
        if (instance == null) {
            instance = new OpenSans();
            typeface = Typeface.createFromAsset(context.getResources().getAssets(), "open_sans.ttf");
        }
        return instance;
    }
}

public Typeface getTypeFace() {
    return typeface;
}
}

Custom TextView:

public class NativelyCustomTextView extends TextView {

    public NativelyCustomTextView(Context context) {
        super(context);
        setTypeface(OpenSans.getInstance(context).getTypeFace());
    }

    public NativelyCustomTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        setTypeface(OpenSans.getInstance(context).getTypeFace());
    }

    public NativelyCustomTextView(Context context, AttributeSet attrs,
            int defStyle) {
        super(context, attrs, defStyle);
        setTypeface(OpenSans.getInstance(context).getTypeFace());
    }

}

By xml:

<com.yourpackage.views.NativelyCustomTextView
            android:id="@+id/natively_text_view"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_margin="20dp"
            android:text="@string/natively"
            android:textSize="30sp" /> 

Programmatically:

TextView programmaticallyTextView = (TextView) 
       findViewById(R.id.programmatically_text_view);

programmaticallyTextView.setTypeface(OpenSans.getInstance(this)
                .getTypeFace());

Visual Studio Code PHP Intelephense Keep Showing Not Necessary Error

If you see this immediately after adding a new Vendor class, be sure to run the VScode command (control-shift-P) Index Workspace

HttpClient won't import in Android Studio

I think depending on which Android Studio version you have, it's important you update your android studio as well, i was becoming frustrated too following everyone's advice but no luck, until i had to upgrade my android version from 1.3 to 1.5, the errors disappeared like magic.

UICollectionView Set number of columns

If you are lazy using delegate.

extension UICollectionView {
    func setItemsInRow(items: Int) {
        if let layout = self.collectionViewLayout as? UICollectionViewFlowLayout {
            let contentInset = self.contentInset
            let itemsInRow: CGFloat = CGFloat(items);
            let innerSpace = layout.minimumInteritemSpacing * (itemsInRow - 1.0)
            let insetSpace = contentInset.left + contentInset.right + layout.sectionInset.left + layout.sectionInset.right
            let width = floor((CGRectGetWidth(frame) - insetSpace - innerSpace) / itemsInRow);
            layout.itemSize = CGSizeMake(width, width)
        }
    }
}

PS: Should be called after rotation too

How do I retrieve a textbox value using JQuery?

You need to use the val() function to get the textbox value. text does not exist as a property only as a function and even then its not the correct function to use in this situation.

var from = $("input#fromAddress").val()

val() is the standard function for getting the value of an input.

How to save image in database using C#

You'll want to convert the image to a byte[] in C#, and then you'll have the database column as varbinary(MAX)

After that, it's just like saving any other data type.

Difference between "as $key => $value" and "as $value" in PHP foreach

Let's say you have an associative array like this:

$a = array(
    "one" => 1,
    "two" => 2,
    "three" => 3,
    "seventeen" => array('x'=>123)
);

In the first iteration : $key="one" and $value=1.

Sometimes you need this key ,if you want only the value , you can avoid using it.

In the last iteration : $key='seventeen' and $value = array('x'=>123) so to get value of the first element in this array value, you need a key, x in this case: $value['x'] =123.

How do I get the n-th level parent of an element in jQuery?

If you have a common parent div you can use parentsUntil() link

eg: $('#element').parentsUntil('.commonClass')

Advantage is that you need not to remember how many generation are there between this element and the common parent(defined by commonclass).

What is the preferred Bash shebang?

#!/bin/sh

as most scripts do not need specific bash feature and should be written for sh.

Also, this makes scripts work on the BSDs, which do not have bash per default.

combining two string variables

you need to take out the quotes:

soda = a + b

(You want to refer to the variables a and b, not the strings "a" and "b")

Adding an external directory to Tomcat classpath

Just specify it in shared.loader or common.loader property of /conf/catalina.properties.

Sort tuples based on second parameter

And if you are using python 3.X, you may apply the sorted function on the mylist. This is just an addition to the answer that @Sven Marnach has given above.

# using *sort method*
mylist.sort(lambda x: x[1]) 

# using *sorted function*
sorted(mylist, key = lambda x: x[1]) 

C# getting the path of %AppData%

I don't think putting %AppData% in a string like that will work.

try

Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData).ToString()

Ruby max integer

as @Jörg W Mittag pointed out: in jruby, fix num size is always 8 bytes long. This code snippet shows the truth:

fmax = ->{
  if RUBY_PLATFORM == 'java'
    2**63 - 1
  else
    2**(0.size * 8 - 2) - 1
  end
}.call

p fmax.class     # Fixnum

fmax = fmax + 1  

p fmax.class     #Bignum

Is there a CSS selector by class prefix?

You can't do this no. There is one attribute selector that matches exactly or partial until a - sign, but it wouldn't work here because you have multiple attributes. If the class name you are looking for would always be first, you could do this:

<html>
<head>
<title>Test Page</title>
<style type="text/css">
div[class|=status] { background-color:red; }
</style>
</head>
<body>
<div id='A' class='status-important bar-class'>A</div>
<div id='B' class='bar-class'>B</div>
<div id='C' class='status-low-priority bar-class'>C</div>

</body>
</html>

Note that this is just to point out which CSS attribute selector is the closest, it is not recommended to assume class names will always be in front since javascript could manipulate the attribute.

How to change python version in anaconda spyder

  1. Set python3 as a main version in the terminal: ln -sf python3 /usr/bin/python

  2. Install pip3: apt-get install python3-pip

  3. Update spyder: pip install -U spyder

Enjoy

Why am I getting Unknown error in line 1 of pom.xml?

You just need a latest Eclipse or Spring tool suite 4.5 and above.Nothing else.refresh project and it works

Printing all properties in a Javascript Object

What about this:

var txt="";
var nyc = {
    fullName: "New York City",
    mayor: "Michael Bloomberg",
    population: 8000000,
    boroughs: 5
};

for (var x in nyc){
    txt += nyc[x];
}

Android Firebase, simply get one child object's data

just fetch specific node data and its working perfect for me

mFirebaseInstance.getReference("yourNodeName").getRef().addValueEventListener(new ValueEventListener() {
    @Override
    public void onDataChange(DataSnapshot dataSnapshot) {


        for (DataSnapshot postSnapshot : dataSnapshot.getChildren()) {
            Log.e(TAG, "======="+postSnapshot.child("email").getValue());
            Log.e(TAG, "======="+postSnapshot.child("name").getValue());
        }
    }

    @Override
    public void onCancelled(DatabaseError error) {
        // Failed to read value
        Log.e(TAG, "Failed to read app title value.", error.toException());
    }
});

Mockito : doAnswer Vs thenReturn

You should use thenReturn or doReturn when you know the return value at the time you mock a method call. This defined value is returned when you invoke the mocked method.

thenReturn(T value) Sets a return value to be returned when the method is called.

@Test
public void test_return() throws Exception {
    Dummy dummy = mock(Dummy.class);
    int returnValue = 5;

    // choose your preferred way
    when(dummy.stringLength("dummy")).thenReturn(returnValue);
    doReturn(returnValue).when(dummy).stringLength("dummy");
}

Answer is used when you need to do additional actions when a mocked method is invoked, e.g. when you need to compute the return value based on the parameters of this method call.

Use doAnswer() when you want to stub a void method with generic Answer.

Answer specifies an action that is executed and a return value that is returned when you interact with the mock.

@Test
public void test_answer() throws Exception {
    Dummy dummy = mock(Dummy.class);
    Answer<Integer> answer = new Answer<Integer>() {
        public Integer answer(InvocationOnMock invocation) throws Throwable {
            String string = invocation.getArgumentAt(0, String.class);
            return string.length() * 2;
        }
    };

    // choose your preferred way
    when(dummy.stringLength("dummy")).thenAnswer(answer);
    doAnswer(answer).when(dummy).stringLength("dummy");
}

Making TextView scrollable on Android

Make your textview just adding this

TextView textview= (TextView) findViewById(R.id.your_textview_id);
textview.setMovementMethod(new ScrollingMovementMethod());

syntaxerror: "unexpected character after line continuation character in python" math

You must press enter after continuation character

Note: Space after continuation character leads to error

cost = {"apples": [3.5, 2.4, 2.3], "bananas": [1.2, 1.8]}

0.9 * average(cost["apples"]) + \ """enter here"""
0.1 * average(cost["bananas"])

Full width image with fixed height

If you don't want to lose the ratio of your image, then don't bother with height:300px; and just use width:100%;.

If the image is too large, then you will have to crop it using an image editor.

Github: Can I see the number of downloads for a repo?

I ended up writing a scraper script to find my clone count:

#!/bin/sh
#
# This script requires:
#   apt-get install html-xml-utils
#   apt-get install jq
#
USERNAME=dougluce
PASSWORD="PASSWORD GOES HERE, BE CAREFUL!"
REPO="dougluce/node-autovivify"

TOKEN=`curl https://github.com/login -s -c /tmp/cookies.txt | \
     hxnormalize | \
     hxselect 'input[name=authenticity_token]' 2>/dev/null | \
     perl -lne 'print $1 if /value=\"(\S+)\"/'`

curl -X POST https://github.com/session \
     -s -b /tmp/cookies.txt -c /tmp/cookies2.txt \
     --data-urlencode commit="Sign in" \
     --data-urlencode authenticity_token="$TOKEN" \
     --data-urlencode login="$USERNAME" \
     --data-urlencode password="$PASSWORD" > /dev/null

curl "https://github.com/$REPO/graphs/clone-activity-data" \
     -s -b /tmp/cookies2.txt \
     -H "x-requested-with: XMLHttpRequest" | jq '.summary'

This'll grab the data from the same endpoint that Github's clone graph uses and spit out the totals from it. The data also includes per-day counts, replace .summary with just . to see those pretty-printed.

How to make a countdown timer in Android?

    var futureMinDate = Date()
    val sdf = SimpleDateFormat("yyyy-MM-dd", Locale.ENGLISH)
    try {
        futureMinDate = sdf.parse("2019-08-22")
    } catch (e: ParseException) {
        e.printStackTrace()
    }

    // Here futureMinDate.time Returns the number of milliseconds since January 1, 1970, 00:00:00 GM
    // So we need to subtract the millis from current millis to get actual millis
    object : CountDownTimer(futureMinDate.time - System.currentTimeMillis(), 1000) {
        override fun onTick(millisUntilFinished: Long) {
            val sec = (millisUntilFinished / 1000) % 60
            val min = (millisUntilFinished / (1000 * 60)) % 60
            val hr = (millisUntilFinished / (1000 * 60 * 60)) % 24
            val day = ((millisUntilFinished / (1000 * 60 * 60)) / 24).toInt()
            val formattedTimeStr = if (day > 1) "$day days $hr : $min : $sec"
            else "$day day $hr : $min : $sec"
            tvFlashDealCountDownTime.text = formattedTimeStr
        }

        override fun onFinish() {
            tvFlashDealCountDownTime.text = "Done!"
        }
    }.start()

Pass a future date and convert it to millisecond.

It will work like a charm.

CSS3 100vh not constant in mobile browser

@nils explained it clearly.

What's next then?

I just went back to use relative 'classic' % (percentage) in CSS.

It's often more effort to implement something than it would be using vh, but at least, you have a pretty stable solution which works across different devices and browsers without strange UI glitches.

How to view user privileges using windows cmd?

Mark Russinovich wrote a terrific tool called AccessChk that lets you get this information from the command line. No installation is necessary.

http://technet.microsoft.com/en-us/sysinternals/bb664922.aspx

For example:

accesschk.exe /accepteula -q -a SeServiceLogonRight

Returns this for me:

IIS APPPOOL\DefaultAppPool
IIS APPPOOL\Classic .NET AppPool
NT SERVICE\ALL SERVICES

By contrast, whoami /priv and whoami /all were missing some entries for me, like SeServiceLogonRight.

How to filter by object property in angularJS

We have Collection as below:


enter image description here

Syntax:

{{(Collection/array/list | filter:{Value : (object value)})[0].KeyName}}

Example:

{{(Collectionstatus | filter:{Value:dt.Status})[0].KeyName}}

-OR-

Syntax:

ng-bind="(input | filter)"

Example:

ng-bind="(Collectionstatus | filter:{Value:dt.Status})[0].KeyName"

How to post data to specific URL using WebClient in C#

Here is the crisp answer:

public String sendSMS(String phone, String token) {
    WebClient webClient = WebClient.create(smsServiceUrl);

    SMSRequest smsRequest = new SMSRequest();
    smsRequest.setMessage(token);
    smsRequest.setPhoneNo(phone);
    smsRequest.setTokenId(smsServiceTokenId);

    Mono<String> response = webClient.post()
          .uri(smsServiceEndpoint)
          .header(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE)
          .body(Mono.just(smsRequest), SMSRequest.class)
          .retrieve().bodyToMono(String.class);

    String deliveryResponse = response.block();
    if (deliveryResponse.equalsIgnoreCase("success")) {
      return deliveryResponse;
    }
    return null;
}

Using async/await with a forEach loop

Instead of Promise.all in conjunction with Array.prototype.map (which does not guarantee the order in which the Promises are resolved), I use Array.prototype.reduce, starting with a resolved Promise:

async function printFiles () {
  const files = await getFilePaths();

  await files.reduce(async (promise, file) => {
    // This line will wait for the last async function to finish.
    // The first iteration uses an already resolved Promise
    // so, it will immediately continue.
    await promise;
    const contents = await fs.readFile(file, 'utf8');
    console.log(contents);
  }, Promise.resolve());
}

How to maximize a plt.show() window using Python

import matplotlib.pyplot as plt
def maximize():
    plot_backend = plt.get_backend()
    mng = plt.get_current_fig_manager()
    if plot_backend == 'TkAgg':
        mng.resize(*mng.window.maxsize())
    elif plot_backend == 'wxAgg':
        mng.frame.Maximize(True)
    elif plot_backend == 'Qt4Agg':
        mng.window.showMaximized()

Then call function maximize() before plt.show()

Converting from Integer, to BigInteger

The method you want is BigInteger#valueOf(long val).

E.g.,

BigInteger bi = BigInteger.valueOf(myInteger.intValue());

Making a String first is unnecessary and undesired.

The model item passed into the dictionary is of type .. but this dictionary requires a model item of type

Observe if the view has the model required:

View

@model IEnumerable<WFAccess.Models.ViewModels.SiteViewModel>

<div class="row">
    <table class="table table-striped table-hover table-width-custom">
        <thead>
            <tr>
....

Controller

[HttpGet]
public ActionResult ListItems()
{
    SiteStore site = new SiteStore();
    site.GetSites();

    IEnumerable<SiteViewModel> sites =
        site.SitesList.Select(s => new SiteViewModel
        {
            Id = s.Id,
            Type = s.Type
        });

    return PartialView("_ListItems", sites);
}

In my case I Use a partial view but runs in normal views

Cannot implicitly convert type 'System.Linq.IQueryable' to 'System.Collections.Generic.IList'

You can use the .ToList() method to convert the IQueryable result returned to an IList, as shown below, after the linq query.

   public DzieckoAndOpiekunCollection GetChildAndOpiekunByFirstnameLastname(string firstname, string lastname)
{
    DataTransfer.ChargeInSchoolEntities db = new DataTransfer.ChargeInSchoolEntities();
    DzieckoAndOpiekunCollection result = new DzieckoAndOpiekunCollection();
    if (firstname == null && lastname != null)
    {
        IList<DzieckoAndOpiekun> resultV = from p in db.Dziecko
                      where lastname == p.Nazwisko
                      **select** new DzieckoAndOpiekun(
                     p.Imie,
                     p.Nazwisko,
                     p.Opiekun.Imie,
                     p.Opiekun.Nazwisko).ToList()
                  ;
        result.AddRange(resultV);
    }
    return result;
}

How to get elements with multiple classes

querySelectorAll with standard class selectors also works for this.

document.querySelectorAll('.class1.class2');

How do I use WebRequest to access an SSL encrypted site using https?

You're doing it the correct way but users may be providing urls to sites that have invalid SSL certs installed. You can ignore those cert problems if you put this line in before you make the actual web request:

ServicePointManager.ServerCertificateValidationCallback = new System.Net.Security.RemoteCertificateValidationCallback(AcceptAllCertifications);

where AcceptAllCertifications is defined as

public bool AcceptAllCertifications(object sender, System.Security.Cryptography.X509Certificates.X509Certificate certification, System.Security.Cryptography.X509Certificates.X509Chain chain, System.Net.Security.SslPolicyErrors sslPolicyErrors)
{
    return true;
}

How can I change the default credentials used to connect to Visual Studio Online (TFSPreview) when loading Visual Studio up?

i found another solution:

  1. start session in TEAM
  2. go to SOURCE CONTROL and select WORKSPACE (mark in red)
  3. then Add new Workspace... why?
  4. because you dont work in the same workspace whey you change your account in TFS (i dont know why)
  5. and ready to MAP your project again.

Its 100% guaranteed to work.

Regular expression to search multiple strings (Textpad)

If I understand what you are asking, it is a regular expression like this:

^(8768|9875|2353)

This matches the three sets of digit strings at beginning of line only.

How to set -source 1.7 in Android Studio and Gradle

Latest Android Studio 1.4.

Click File->Project Structure->SDK Location->JDK Location.

You could also set individual module JDK Version compatibility by going to the Module (below the SDK Location), and edit the Source Compatibility accordingly. (note, this only applies to Android Module).

How to tell if a <script> tag failed to load

This can be done safely using promises

    function loadScript(src) {
      return new Promise(function(resolve, reject) {
        let script = document.createElement('script');
        script.src = src;
    
        script.onload = () => resolve(script);
        script.onerror = () => reject(new Error("Script load error: " + src));
    
        document.head.append(script);
      });
    }

and use like this

    let promise = loadScript("https://cdnjs.cloudflare.com/ajax/libs/lodash.js/3.2.0/lodash.js");
    
    promise.then(
      script => alert(`${script.src} is loaded!`),
      error => alert(`Error: ${error.message}`)
    );

How to style the UL list to a single line

In modern browsers you can do the following (CSS3 compliant)

_x000D_
_x000D_
ul_x000D_
{_x000D_
  display:flex;  _x000D_
  list-style:none;_x000D_
}
_x000D_
<ul>_x000D_
  <li><a href="">Item1</a></li>_x000D_
  <li><a href="">Item2</a></li>_x000D_
  <li><a href="">Item3</a></li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

Run JavaScript in Visual Studio Code

Just install nodemon and run

nodemon your_file.js

on vs code terminal.

Using NotNull Annotation in method argument

To test your method validation in a test, you have to wrap it a proxy in the @Before method.

@Before
public void setUp() {
    this.classAutowiredWithFindStuffMethod = MethodValidationProxyFactory.createProxy(this.classAutowiredWithFindStuffMethod);
}

With MethodValidationProxyFactory as :

import org.springframework.context.support.StaticApplicationContext;
import org.springframework.validation.beanvalidation.MethodValidationPostProcessor;

public class MethodValidationProxyFactory {

private static final StaticApplicationContext ctx = new StaticApplicationContext();

static {
    MethodValidationPostProcessor processor = new MethodValidationPostProcessor();
    processor.afterPropertiesSet(); // init advisor
    ctx.getBeanFactory()
            .addBeanPostProcessor(processor);
}

@SuppressWarnings("unchecked")
public static <T> T createProxy(T instance) {

    return (T) ctx.getAutowireCapableBeanFactory()
            .applyBeanPostProcessorsAfterInitialization(instance, instance.getClass()
                    .getName());
}

}

And then, add your test :

@Test
public void findingNullStuff() {
 assertThatExceptionOfType(ConstraintViolationException.class).isThrownBy(() -> this.classAutowiredWithFindStuffMethod.findStuff(null));

}

<img>: Unsafe value used in a resource URL context

I usually add separate safe pipe reusable component as following

# Add Safe Pipe

import { Pipe, PipeTransform } from '@angular/core';
import { DomSanitizer } from '@angular/platform-browser';

@Pipe({name: 'mySafe'})
export class SafePipe implements PipeTransform {
    constructor(private sanitizer: DomSanitizer) {
    }

    public transform(url) {
        return this.sanitizer.bypassSecurityTrustResourceUrl(url);
    }
}
# then create shared pipe module as following 

import { NgModule } from '@angular/core'; 
import { SafePipe } from './safe.pipe';
@NgModule({
    declarations: [
        SafePipe
    ],
    exports: [
        SafePipe
    ]
})
export class SharedPipesModule {
}
# import shared pipe module in your native module

@NgModule({
    declarations: [],
    imports: [
        SharedPipesModule,
    ],
})
export class SupportModule {
}
<!-------------------
call your url (`trustedUrl` for me) and add `mySafe` as defined in Safe Pipe
---------------->
<div class="container-fluid" *ngIf="trustedUrl">
    <iframe [src]="trustedUrl | mySafe" align="middle" width="100%" height="800" frameborder="0"></iframe>
</div>

The action or event has been blocked by Disabled Mode

Another issue is that your database may be in a "non-trusted" location. Go to the trust center settings and add your database location to the trusted locations list.

create table with sequence.nextval in oracle

Oracle 12c

We now finally have IDENTITY columns like many other databases, in case of which a sequence is auto-generated behind the scenes. This solution is much faster than a trigger-based one as can be seen in this blog post.

So, your table creation would look like this:

CREATE TABLE qname
(
    qname_id integer GENERATED BY DEFAULT AS IDENTITY (START WITH 1) NOT NULL PRIMARY KEY,
    qname    VARCHAR2(4000) NOT NULL -- CONSTRAINT qname_uk UNIQUE
);

Oracle 11g and below

According to the documentation, you cannot do that:

Restriction on Default Column Values A DEFAULT expression cannot contain references to PL/SQL functions or to other columns, the pseudocolumns CURRVAL, NEXTVAL, LEVEL, PRIOR, and ROWNUM, or date constants that are not fully specified.

The standard way to have "auto increment" columns in Oracle is to use triggers, e.g.

CREATE OR REPLACE TRIGGER my_trigger
  BEFORE INSERT 
  ON qname
  FOR EACH ROW
  -- Optionally restrict this trigger to fire only when really needed
  WHEN (new.qname_id is null)
DECLARE
  v_id qname.qname_id%TYPE;
BEGIN
  -- Select a new value from the sequence into a local variable. As David
  -- commented, this step is optional. You can directly select into :new.qname_id
  SELECT qname_id_seq.nextval INTO v_id FROM DUAL;

  -- :new references the record that you are about to insert into qname. Hence,
  -- you can overwrite the value of :new.qname_id (qname.qname_id) with the value
  -- obtained from your sequence, before inserting
  :new.qname_id := v_id;
END my_trigger;

Read more about Oracle TRIGGERs in the documentation

Why am I suddenly getting a "Blocked loading mixed active content" issue in Firefox?

If you are consuming an internal service via AJAX, make sure the url points to https, this cleared up the error for me.

Initial AJAX URL: "http://XXXXXX.com/Core.svc/" + ApiName
Corrected AJAX URL: "https://XXXXXX.com/Core.svc/" + ApiName,

How to show/hide JPanels in a JFrame?

You can hide a JPanel by calling setVisible(false). For example:

public static void main(String args[]){
    JFrame f = new JFrame();
    f.setLayout(new BorderLayout());
    final JPanel p = new JPanel();
    p.add(new JLabel("A Panel"));
    f.add(p, BorderLayout.CENTER);

    //create a button which will hide the panel when clicked.
    JButton b = new JButton("HIDE");
    b.addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e){
                p.setVisible(false);
        }
    });

    f.add(b,BorderLayout.SOUTH);
    f.pack();
    f.setVisible(true);
}

Using setTimeout to delay timing of jQuery actions

.html() only takes a string OR a function as an argument, not both. Try this:

 $("#showDiv").click(function () {
     $('#theDiv').show(1000, function () {
         setTimeout(function () {
             $('#theDiv').html(function () {
                 setTimeout(function () {
                     $('#theDiv').html('Here is some replacement text');
                 }, 0);
                 setTimeout(function () {
                     $('#theDiv').html('More replacement text goes here');
                 }, 2500);
             });
         }, 2500);
     });
 }); //click function ends

jsFiddle example

Calculate row means on subset of columns

(Another solution using pivot_longer & pivot_wider from latest Tidyr update)

You should try using pivot_longer to get your data from wide to long form Read latest tidyR update on pivot_longer & pivot_wider (https://tidyr.tidyverse.org/articles/pivot.html)

library(tidyverse)
C1<-c(3,2,4,4,5)
C2<-c(3,7,3,4,5)
C3<-c(5,4,3,6,3)
DF<-data.frame(ID=c("A","B","C","D","E"),C1=C1,C2=C2,C3=C3)

Output here

  ID     mean
  <fct> <dbl>
1 A      3.67
2 B      4.33
3 C      3.33
4 D      4.67
5 E      4.33

GCC: array type has incomplete element type

The compiler needs to know the size of the second dimension in your two dimensional array. For example:

void print_graph(g_node graph_node[], double weight[][5], int nodes);

Custom height Bootstrap's navbar

You need also to set .min-height: 0px; please see bellow:

.navbar-inner {
    min-height: 0px;
}

.navbar-brand,
.navbar-nav li a {
    line-height: 150px;
    height: 150px;
    padding-top: 0;
}

If you set .min-height: 0px; then you can choose any height you want!

Good Luck!

Intellij idea cannot resolve anything in maven

If you have any dependencies in pom.xml specific to your organisation than you need to update path of setting.xml for your project which is by default set to your user directory in Ubuntu : /home/user/.m2/settings.xml -> (change it to your apache-maven conf path)

Update Setting.xml file Intellij

How to make bootstrap column height to 100% row height?

You can solve that using display table.

Here is the updated JSFiddle that solves your problem.

CSS

.body {
    display: table;
    background-color: green;
}

.left-side {
    background-color: blue;
    float: none;
    display: table-cell;
    border: 1px solid;
}

.right-side {
    background-color: red;
    float: none;
    display: table-cell;
    border: 1px solid;
}

HTML

<div class="row body">
        <div class="col-xs-9 left-side">
            <p>sdfsdf</p>
            <p>sdfsdf</p>
            <p>sdfsdf</p>
            <p>sdfsdf</p>
            <p>sdfsdf</p>
            <p>sdfsdf</p>
        </div>
        <div class="col-xs-3 right-side">
            asdfdf
        </div>
    </div>

How to fix C++ error: expected unqualified-id

As a side note, consider passing strings in setWord() as const references to avoid excess copying. Also, in displayWord, consider making this a const function to follow const-correctness.

void setWord(const std::string& word) {
  theWord = word;
}

SELECT list is not in GROUP BY clause and contains nonaggregated column

As @Brian Riley already said you should either remove 1 column in your select

select countrylanguage.language ,sum(country.population*countrylanguage.percentage/100)
from countrylanguage
join country on countrylanguage.countrycode = country.code
group by countrylanguage.language
order by sum(country.population*countrylanguage.percentage) desc ;

or add it to your grouping

select countrylanguage.language, country.code, sum(country.population*countrylanguage.percentage/100)
from countrylanguage
join country on countrylanguage.countrycode = country.code
group by countrylanguage.language, country.code
order by sum(country.population*countrylanguage.percentage) desc ;

Getting the "real" Facebook profile picture URL from graph API

$url = 'http://graph.facebook.com/100000771470028/picture?type=large';
$rray=get_headers($url);
$hd = $rray[4];
echo(substr($hd,strpos($hd,'http')));

This will return the url that you asked, and the problem of changing the url by facebook doesn't matter because you are dynamically calling the url from the original url.

pip install from git repo branch

This worked like charm:

pip3 install git+https://github.com/deepak1725/fabric8-analytics-worker.git@develop

Where :

develop: Branch

fabric8-analytics-worker.git : Repo

deepak1725: user

Commit history on remote repository

This is what worked for me:

git fetch --all 
git log production/master

Note that this fetches from ALL remotes, i.e. potentially you "have to clone 2GB worth of objects just to look through the commit logs".

Laravel Unknown Column 'updated_at'

For those who are using laravel 5 or above must use public modifier other wise it will throw an exception

Access level to App\yourModelName::$timestamps must be
public (as in class Illuminate\Database\Eloquent\Model)

public $timestamps = false;

How to export a table dataframe in PySpark to csv?

You need to repartition the Dataframe in a single partition and then define the format, path and other parameter to the file in Unix file system format and here you go,

df.repartition(1).write.format('com.databricks.spark.csv').save("/path/to/file/myfile.csv",header = 'true')

Read more about the repartition function Read more about the save function

However, repartition is a costly function and toPandas() is worst. Try using .coalesce(1) instead of .repartition(1) in previous syntax for better performance.

Read more on repartition vs coalesce functions.

How do I reload a page without a POSTDATA warning in Javascript?

I've written a function that will reload the page without post submission and it will work with hashes, too.

I do this by adding / modifying a GET parameter in the URL called reload by updating its value with the current timestamp in ms.

var reload = function () {
    var regex = new RegExp("([?;&])reload[^&;]*[;&]?");
    var query = window.location.href.split('#')[0].replace(regex, "$1").replace(/&$/, '');
    window.location.href =
        (window.location.href.indexOf('?') < 0 ? "?" : query + (query.slice(-1) != "?" ? "&" : ""))
        + "reload=" + new Date().getTime() + window.location.hash;
};

Keep in mind, if you want to trigger this function in a href attribute, implement it this way: href="javascript:reload();void 0;" to make it work, successfully.

The downside of my solution is it will change the URL, so this "reload" is not a real reload, instead it's a load with a different query. Still, it could fit your needs like it does for me.

How can I lock the first row and first column of a table when scrolling, possibly using JavaScript and CSS?

How about a solution where you put the actual "data" of the table inside its own div, with overflow: scroll;? Then the browser will automatically create scrollbars for the portion of the "table" you do not want to lock, and you can put the "table header"/first row just above that <div>.

Not sure how that would work with scrolling horizontally though.

What is Teredo Tunneling Pseudo-Interface?

Unless you have some kind of really weird problem, keep it. The number of IPv6 sites is very small, but there are some and it will let you get to them even if you're at an IPv4 only location.

If it is causing you a problem, it's best to fix it. I've seen a number of people recommending removing it to solve problems. However, they're not actually solving the root cause of the issue. In all the cases I've seen, removing Teredo just happens to cause a side-effect that fixes their problem... :)

How to find the mysql data directory from command line in windows

You can see the complete list of MySQL server options by running

mysqld --verbose --help

For example, to find out the path to the data directory on Linux, you can run:

mysqld --verbose --help | grep ^datadir

Example output:

datadir                                     /var/lib/mysql/

How to run two jQuery animations simultaneously?

See this brilliant blog post about animating values in objects.. you can then use the values to animate whatever you like, 100% simultaneously!

http://www.josscrowcroft.com/2011/code/jquery-animate-increment-decrement-numeric-text-elements-value/

I've used it like this to slide in/out:

        slide : function(id, prop, from, to) {
            if (from < to) {
                // Sliding out
                var fromvals = { add: from, subtract: 0 };
                var tovals = { add: to, subtract: 0 };
            } else {
                // Sliding back in
                var fromvals = { add: from, subtract: to };
                var tovals = { add: from, subtract: from };
            }

            $(fromvals).animate(tovals, {
                duration: 200,
                easing: 'swing', // can be anything
                step: function () { // called on every step
                    // Slide using the entire -ms-grid-columns setting
                    $(id).css(prop, (this.add - this.subtract) + 'px 1.5fr 0.3fr 8fr 3fr 5fr 0.5fr');
                }
            });
        }

What is your most productive shortcut with Vim?

In addition to the great reply about grokking vi, it should be noted that vim does add some very vi-like features that make using vi commands nicer. The one that comes to mind first are text objects: instead of {!}fmt to reformat the current paragraph, !apfmt does the same. It works by first specifying that we want to select a text object, which is the current paragraph. Similar, to change the current string literal (foo to bar for an example), instead of T"ct"bar (move to just after the previous ", change until just before the next ", insert bar), you can say ci"bar: change inside (innermost) quotes, inserting bar.

Thinking in terms of text objects instead of movement commands is quite nice.

"Adaptive Server is unavailable or does not exist" error connecting to SQL Server from PHP

1. See information about the SQL server

tsql -LH SERVER_IP_ADDRESS

locale is "C"
locale charset is "646"
ServerName TITAN
InstanceName MSSQLSERVER
IsClustered No
Version 8.00.194
tcp 1433
np \\TITAN\pipe\sql\query

2. Set your freetds.conf

tsql -C    
freetds.conf directory: /usr/local/etc

[TITAN]
host = SERVER_IP_ADDRESS
port = 1433
tds version = 7.2

3 Try

tsql -S TITAN -U user -P password

OR

 'dsn' => 'dblib:host=TITAN:1433;dbname=YOURDBNAME',

See also http://www.freetds.org/userguide/confirminstall.htm (Example 3-5.)

If you get message 20009, remember you haven't connected to the machine. It's a configuration or network issue, not a protocol failure. Verify the server is up, has the name and IP address FreeTDS is using, and is listening to the configured port.

How to programmatically empty browser cache?

_x000D_
_x000D_
//The code below should be put in the "js" folder with the name "clear-browser-cache.js"_x000D_
_x000D_
(function () {_x000D_
    var process_scripts = false;_x000D_
    var rep = /.*\?.*/,_x000D_
    links = document.getElementsByTagName('link'),_x000D_
    scripts = document.getElementsByTagName('script');_x000D_
    var value = document.getElementsByName('clear-browser-cache');_x000D_
    for (var i = 0; i < value.length; i++) {_x000D_
        var val = value[i],_x000D_
            outerHTML = val.outerHTML;_x000D_
        var check = /.*value="true".*/;_x000D_
        if (check.test(outerHTML)) {_x000D_
            process_scripts = true;_x000D_
        }_x000D_
    }_x000D_
    for (var i = 0; i < links.length; i++) {_x000D_
        var link = links[i],_x000D_
        href = link.href;_x000D_
        if (rep.test(href)) {_x000D_
            link.href = href + '&' + Date.now();_x000D_
        }_x000D_
        else {_x000D_
            link.href = href + '?' + Date.now();_x000D_
        }_x000D_
    }_x000D_
    if (process_scripts) {_x000D_
        for (var i = 0; i < scripts.length; i++) {_x000D_
            var script = scripts[i],_x000D_
            src = script.src;_x000D_
            if (src !== "") {_x000D_
                if (rep.test(src)) {_x000D_
                    script.src = src + '&' + Date.now();_x000D_
                }_x000D_
                else {_x000D_
                    script.src = src + '?' + Date.now();_x000D_
                }_x000D_
            }_x000D_
        }_x000D_
    }_x000D_
})();
_x000D_
At the end of the tah head, place the line at the code below_x000D_
_x000D_
    < script name="clear-browser-cache" src='js/clear-browser-cache.js' value="true" >< /script >
_x000D_
_x000D_
_x000D_

Ternary operator ?: vs if...else

In C A ternary operator " ? : " is available to construct conditional expressions of the form

exp1 ? exp2:exp3

where exp1,exp2 and exp3 are expressions

for Example

        a=20;
        b=25;
        x=(a>b)?a:b;

        in the above example x value will be assigned to b;

This can be written using if..else statement as follows

            if (a>b)
             x=a;
             else
             x=b;

**Hence there is no difference between these two. This for the programmer to write easily, but for compiler both are same.*

Error: 0xC0202009 at Data Flow Task, OLE DB Destination [43]: SSIS Error Code DTS_E_OLEDBERROR. An OLE DB error has occurred. Error code: 0x80040E21

It is also possible to receive this error from a select component if the query fails in an unusual manner (eg: a sub-query returns multiple rows in an oracle oledb connection)

How to draw vertical lines on a given plot in matplotlib

For multiple lines

xposition = [0.3, 0.4, 0.45]
for xc in xposition:
    plt.axvline(x=xc, color='k', linestyle='--')

Truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all()

You need to use bitwise operators | instead of or and & instead of and in pandas, you can't simply use the bool statements from python.

For much complex filtering create a mask and apply the mask on the dataframe.
Put all your query in the mask and apply it.
Suppose,

mask = (df["col1"]>=df["col2"]) & (stock["col1"]<=df["col2"])
df_new = df[mask]

How to create a template function within a class? (C++)

Your guess is the correct one. The only thing you have to remember is that the member function template definition (in addition to the declaration) should be in the header file, not the cpp, though it does not have to be in the body of the class declaration itself.

Using Service to run background and create notification

The question is relatively old, but I hope this post still might be relevant for others.

TL;DR: use AlarmManager to schedule a task, use IntentService, see the sample code here;

What this test-application(and instruction) is about:

Simple helloworld app, which sends you notification every 2 hours. Clicking on notification - opens secondary Activity in the app; deleting notification tracks.

When should you use it:

Once you need to run some task on a scheduled basis. My own case: once a day, I want to fetch new content from server, compose a notification based on the content I got and show it to user.

What to do:

  1. First, let's create 2 activities: MainActivity, which starts notification-service and NotificationActivity, which will be started by clicking notification:

    activity_main.xml

    <?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:padding="16dp">
        <Button
            android:id="@+id/sendNotifications"
            android:onClick="onSendNotificationsButtonClick"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Start Sending Notifications Every 2 Hours!" />
    </RelativeLayout>
    

    MainActivity.java

    public class MainActivity extends AppCompatActivity {
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
        }
    
        public void onSendNotificationsButtonClick(View view) {
            NotificationEventReceiver.setupAlarm(getApplicationContext());
        }   
    }
    

    and NotificationActivity is any random activity you can come up with. NB! Don't forget to add both activities into AndroidManifest.

  2. Then let's create WakefulBroadcastReceiver broadcast receiver, I called NotificationEventReceiver in code above.

    Here, we'll set up AlarmManager to fire PendingIntent every 2 hours (or with any other frequency), and specify the handled actions for this intent in onReceive() method. In our case - wakefully start IntentService, which we'll specify in the later steps. This IntentService would generate notifications for us.

    Also, this receiver would contain some helper-methods like creating PendintIntents, which we'll use later

    NB1! As I'm using WakefulBroadcastReceiver, I need to add extra-permission into my manifest: <uses-permission android:name="android.permission.WAKE_LOCK" />

    NB2! I use it wakeful version of broadcast receiver, as I want to ensure, that the device does not go back to sleep during my IntentService's operation. In the hello-world it's not that important (we have no long-running operation in our service, but imagine, if you have to fetch some relatively huge files from server during this operation). Read more about Device Awake here.

    NotificationEventReceiver.java

    public class NotificationEventReceiver extends WakefulBroadcastReceiver {
    
        private static final String ACTION_START_NOTIFICATION_SERVICE = "ACTION_START_NOTIFICATION_SERVICE";
        private static final String ACTION_DELETE_NOTIFICATION = "ACTION_DELETE_NOTIFICATION";
        private static final int NOTIFICATIONS_INTERVAL_IN_HOURS = 2;
    
        public static void setupAlarm(Context context) {
            AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
            PendingIntent alarmIntent = getStartPendingIntent(context);
            alarmManager.setRepeating(AlarmManager.RTC_WAKEUP,
                    getTriggerAt(new Date()),
                    NOTIFICATIONS_INTERVAL_IN_HOURS * AlarmManager.INTERVAL_HOUR,
                    alarmIntent);
        }
    
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            Intent serviceIntent = null;
            if (ACTION_START_NOTIFICATION_SERVICE.equals(action)) {
                Log.i(getClass().getSimpleName(), "onReceive from alarm, starting notification service");
                serviceIntent = NotificationIntentService.createIntentStartNotificationService(context);
            } else if (ACTION_DELETE_NOTIFICATION.equals(action)) {
                Log.i(getClass().getSimpleName(), "onReceive delete notification action, starting notification service to handle delete");
                serviceIntent = NotificationIntentService.createIntentDeleteNotification(context);
            }
    
            if (serviceIntent != null) {
                startWakefulService(context, serviceIntent);
            }
        }
    
        private static long getTriggerAt(Date now) {
            Calendar calendar = Calendar.getInstance();
            calendar.setTime(now);
            //calendar.add(Calendar.HOUR, NOTIFICATIONS_INTERVAL_IN_HOURS);
            return calendar.getTimeInMillis();
        }
    
        private static PendingIntent getStartPendingIntent(Context context) {
            Intent intent = new Intent(context, NotificationEventReceiver.class);
            intent.setAction(ACTION_START_NOTIFICATION_SERVICE);
            return PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
        }
    
        public static PendingIntent getDeleteIntent(Context context) {
            Intent intent = new Intent(context, NotificationEventReceiver.class);
            intent.setAction(ACTION_DELETE_NOTIFICATION);
            return PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
        }
    }
    
  3. Now let's create an IntentService to actually create notifications.

    There, we specify onHandleIntent() which is responses on NotificationEventReceiver's intent we passed in startWakefulService method.

    If it's Delete action - we can log it to our analytics, for example. If it's Start notification intent - then by using NotificationCompat.Builder we're composing new notification and showing it by NotificationManager.notify. While composing notification, we are also setting pending intents for click and remove actions. Fairly Easy.

    NotificationIntentService.java

    public class NotificationIntentService extends IntentService {
    
        private static final int NOTIFICATION_ID = 1;
        private static final String ACTION_START = "ACTION_START";
        private static final String ACTION_DELETE = "ACTION_DELETE";
    
        public NotificationIntentService() {
            super(NotificationIntentService.class.getSimpleName());
        }
    
        public static Intent createIntentStartNotificationService(Context context) {
            Intent intent = new Intent(context, NotificationIntentService.class);
            intent.setAction(ACTION_START);
            return intent;
        }
    
        public static Intent createIntentDeleteNotification(Context context) {
            Intent intent = new Intent(context, NotificationIntentService.class);
            intent.setAction(ACTION_DELETE);
            return intent;
        }
    
        @Override
        protected void onHandleIntent(Intent intent) {
            Log.d(getClass().getSimpleName(), "onHandleIntent, started handling a notification event");
            try {
                String action = intent.getAction();
                if (ACTION_START.equals(action)) {
                    processStartNotification();
                }
                if (ACTION_DELETE.equals(action)) {
                    processDeleteNotification(intent);
                }
            } finally {
                WakefulBroadcastReceiver.completeWakefulIntent(intent);
            }
        }
    
        private void processDeleteNotification(Intent intent) {
            // Log something?
        }
    
        private void processStartNotification() {
            // Do something. For example, fetch fresh data from backend to create a rich notification?
    
            final NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
            builder.setContentTitle("Scheduled Notification")
                    .setAutoCancel(true)
                    .setColor(getResources().getColor(R.color.colorAccent))
                    .setContentText("This notification has been triggered by Notification Service")
                    .setSmallIcon(R.drawable.notification_icon);
    
            PendingIntent pendingIntent = PendingIntent.getActivity(this,
                    NOTIFICATION_ID,
                    new Intent(this, NotificationActivity.class),
                    PendingIntent.FLAG_UPDATE_CURRENT);
            builder.setContentIntent(pendingIntent);
            builder.setDeleteIntent(NotificationEventReceiver.getDeleteIntent(this));
    
            final NotificationManager manager = (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
            manager.notify(NOTIFICATION_ID, builder.build());
        }
    }
    
  4. Almost done. Now I also add broadcast receiver for BOOT_COMPLETED, TIMEZONE_CHANGED, and TIME_SET events to re-setup my AlarmManager, once device has been rebooted or timezone has changed (For example, user flown from USA to Europe and you don't want notification to pop up in the middle of the night, but was sticky to the local time :-) ).

    NotificationServiceStarterReceiver.java

    public final class NotificationServiceStarterReceiver extends BroadcastReceiver {
    
        @Override
        public void onReceive(Context context, Intent intent) {
            NotificationEventReceiver.setupAlarm(context);
        }
    }
    
  5. We need to also register all our services, broadcast receivers in AndroidManifest:

    <?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="klogi.com.notificationbyschedule">
    
        <uses-permission android:name="android.permission.INTERNET" />
        <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
        <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
        <uses-permission android:name="android.permission.WAKE_LOCK" />
    
        <application
            android:allowBackup="true"
            android:icon="@mipmap/ic_launcher"
            android:label="@string/app_name"
            android:supportsRtl="true"
            android:theme="@style/AppTheme">
            <activity android:name=".MainActivity">
                <intent-filter>
                    <action android:name="android.intent.action.MAIN" />
    
                    <category android:name="android.intent.category.LAUNCHER" />
                </intent-filter>
            </activity>
    
            <service
                android:name=".notifications.NotificationIntentService"
                android:enabled="true"
                android:exported="false" />
    
            <receiver android:name=".broadcast_receivers.NotificationEventReceiver" />
            <receiver android:name=".broadcast_receivers.NotificationServiceStarterReceiver">
                <intent-filter>
                    <action android:name="android.intent.action.BOOT_COMPLETED" />
                    <action android:name="android.intent.action.TIMEZONE_CHANGED" />
                    <action android:name="android.intent.action.TIME_SET" />
                </intent-filter>
            </receiver>
    
            <activity
                android:name=".NotificationActivity"
                android:label="@string/title_activity_notification"
                android:theme="@style/AppTheme.NoActionBar"/>
        </application>
    
    </manifest>
    

That's it!

The source code for this project you can find here. I hope, you will find this post helpful.

Can the :not() pseudo-class have multiple arguments?

If you're using SASS in your project, I've built this mixin to make it work the way we all want it to:

@mixin not($ignorList...) {
    //if only a single value given
    @if (length($ignorList) == 1){
        //it is probably a list variable so set ignore list to the variable
        $ignorList: nth($ignorList,1);
    }
    //set up an empty $notOutput variable
    $notOutput: '';
    //for each item in the list
    @each $not in $ignorList {
        //generate a :not([ignored_item]) segment for each item in the ignore list and put them back to back
        $notOutput: $notOutput + ':not(#{$not})';
    }
    //output the full :not() rule including all ignored items
    &#{$notOutput} {
        @content;
    }
}

it can be used in 2 ways:

Option 1: list the ignored items inline

input {
  /*non-ignored styling goes here*/
  @include not('[type="radio"]','[type="checkbox"]'){
    /*ignored styling goes here*/
  }
}

Option 2: list the ignored items in a variable first

$ignoredItems:
  '[type="radio"]',
  '[type="checkbox"]'
;

input {
  /*non-ignored styling goes here*/
  @include not($ignoredItems){
    /*ignored styling goes here*/
  }
}

Outputted CSS for either option

input {
    /*non-ignored styling goes here*/
}

input:not([type="radio"]):not([type="checkbox"]) {
    /*ignored styling goes here*/
}

System.Net.WebException: The operation has timed out

proxy issue can cause this. IIS webconfig put this in

<defaultProxy useDefaultCredentials="true" enabled="true">
          <proxy usesystemdefault="True" />
        </defaultProxy>

PHP 5 disable strict standards error

For no errors.

error_reporting(0);

or for just not strict

error_reporting(E_ALL ^ E_STRICT);

and if you ever want to display all errors again, use

error_reporting(-1);

Loop through each cell in a range of cells when given a Range object

I'm resurrecting the dead here, but because a range can be defined as "A:A", using a for each loop ends up with a potential infinite loop. The solution, as far as I know, is to use the Do Until loop.

Do Until Selection.Value = ""
  Rem Do things here...
Loop

Configure cron job to run every 15 minutes on Jenkins

Your syntax is slightly wrong. Say:

*/15 * * * * command
  |
  |--> `*/15` would imply every 15 minutes.

* indicates that the cron expression matches for all values of the field.

/ describes increments of ranges.

JSONDecodeError: Expecting value: line 1 column 1 (char 0)

I had exactly this issue using requests. Thanks to Christophe Roussy for his explanation.

To debug, I used:

response = requests.get(url)
logger.info(type(response))

I was getting a 404 response back from the API.

How to load a resource bundle from a file resource in Java?

ResourceBundle rb = ResourceBundle.getBundle("service"); //service.properties
System.out.println(rb.getString("server.dns")); //server.dns=http://....

How to calculate md5 hash of a file using javascript

I've made a library that implements incremental md5 in order to hash large files efficiently. Basically you read a file in chunks (to keep memory low) and hash it incrementally. You got basic usage and examples in the readme.

Be aware that you need HTML5 FileAPI, so be sure to check for it. There is a full example in the test folder.

https://github.com/satazor/SparkMD5

Sort array by value alphabetically php

You want the php function "asort":

http://php.net/manual/en/function.asort.php

it sorts the array, maintaining the index associations.

Edit: I've just noticed you're using a standard array (non-associative). if you're not fussed about preserving index associations, use sort():

http://php.net/manual/en/function.sort.php

Very simple log4j2 XML configuration file using Console and File appender

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="INFO">
    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n" />
        </Console>
        <File name="MyFile" fileName="all.log" immediateFlush="false" append="false">
            <PatternLayout pattern="%d{yyy-MM-dd HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
        </File>
    </Appenders>
    <Loggers>
        <Root level="debug">
            <AppenderRef ref="Console" />
            <AppenderRef ref="MyFile"/>
        </Root>
    </Loggers>
</Configuration>

Notes:

  • Put the following content in your configuration file.
  • Name the configuration file log4j2.xml
  • Put the log4j2.xml in a folder which is in the class-path (i.e. your source folder "src")
  • Use Logger logger = LogManager.getLogger(); to initialize your logger
  • I did set the immediateFlush="false" since this is better for SSD lifetime. If you need the log right away in your log-file remove the parameter or set it to true

Check if table exists without using "select from"

There are several issues to note with the answers here:

1) INFORMATION_SCHEMA.TABLES does not include TEMPORARY tables.

2) Using any type of SHOW query, i.e. SHOW TABLES LIKE 'test_table', will force the return of a resultset to the client, which is undesired behavior for checking if a table exists server-side, from within a stored procedure that also returns a resultset.

3) As some users mentioned, you have to be careful with how you use SELECT 1 FROM test_table LIMIT 1.

If you do something like:

SET @table_exists = 0;
SET @table_exists = (SELECT 1 FROM test_table LIMIT 1);

You will not get the expected result if the table has zero rows.

Below is a stored procedure that will work for all tables (even TEMPORARY).

It can be used like:

SET @test_table = 'test_table';
SET @test_db = NULL;
SET @does_table_exist = NULL;

CALL DoesTableExist(@test_table, @test_db, @does_table_exist);

SELECT @does_table_exist;

The code:

/*
    p_table_name is required
    p_database_name is optional
        if NULL is given for p_database_name, then it defaults to the currently selected database
    p_does_table_exist
        The @variable to save the result to

    This procedure attempts to
        SELECT NULL FROM `p_database_name`.`p_table_name` LIMIT 0;

    If [SQLSTATE '42S02'] is raised, then
        SET p_does_table_exist = 0
    Else
        SET p_does_table_exist = 1

    Info on SQLSTATE '42S02' at:
        https://dev.mysql.com/doc/refman/5.7/en/server-error-reference.html#error_er_no_such_table
*/

DELIMITER $$

DROP PROCEDURE IF EXISTS DoesTableExist
$$

CREATE PROCEDURE         DoesTableExist (
    IN p_table_name VARCHAR(64),
    IN p_database_name VARCHAR(64),
    OUT p_does_table_exist TINYINT(1) UNSIGNED
)
BEGIN
    /* 793441 is used in this procedure for ensuring that user variables have unique names */

    DECLARE EXIT HANDLER FOR SQLSTATE '42S02'
    BEGIN
        SET p_does_table_exist = 0
        ;
    END
    ;


    IF p_table_name IS NULL THEN
        SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = 'DoesTableExist received NULL for p_table_name.';
    END IF;


    /* redirect resultset to a dummy variable */

    SET @test_select_sql_793441 = CONCAT(
        "SET @dummy_var_793441 = ("
            " SELECT"
                " NULL"
            " FROM ",
                IF(
                    p_database_name IS NULL,
                    "",
                    CONCAT(
                        "`",
                        REPLACE(p_database_name, "`", "``"),
                        "`."
                    )
                ),
                "`",
                REPLACE(p_table_name, "`", "``"),
                "`"
            " LIMIT 0"
        ")"
    )
    ;

    PREPARE _sql_statement FROM @test_select_sql_793441
    ;
    SET @test_select_sql_793441 = NULL
    ;
    EXECUTE _sql_statement
    ;
    DEALLOCATE PREPARE _sql_statement
    ;

    SET p_does_table_exist = 1
    ;
END
$$

DELIMITER ;

Google maps Places API V3 autocomplete - select first option on enter

How about this?

$("input").keypress(function(event) {
  var firstValue = null;
  if (event.keyCode == 13 || event.keyCode == 9) {
    $(event.target).blur();
    if ($(".pac-container .pac-item:first span:eq(3)").text() == "") {
      firstValue = $(".pac-container .pac-item:first .pac-item-query").text();
    } else {
      firstValue = $(".pac-container .pac-item:first .pac-item-query").text() + ", " + $(".pac-container .pac-item:first span:eq(3)").text();
    }
    event.target.value = firstValue;
  } else
    return true;
});

What are the most useful Intellij IDEA keyboard shortcuts?

By far my favourite all purpose shortcut is Ctrl+Shift+A

It does a search as you type through all the commands in intellij. Not only that but when you find the command you want it also displays the corresponding shortcut key next to it!

Execute method on startup in Spring

You can use @EventListener on your component, which will be invoked after the server is started and all beans initialized.

@EventListener
public void onApplicationEvent(ContextClosedEvent event) {

}

Directory.GetFiles: how to get only filename, not full path?

You can use System.IO.Path.GetFileName to do this.

E.g.,

string[] files = Directory.GetFiles(dir);
foreach(string file in files)
    Console.WriteLine(Path.GetFileName(file));

While you could use FileInfo, it is much more heavyweight than the approach you are already using (just retrieving file paths). So I would suggest you stick with GetFiles unless you need the additional functionality of the FileInfo class.

How to change facebook login button with my custom image

Found a site on google explaining some changes, according to the author of the page fb does not allow custom buttons. Heres the website.

Unfortunately, it’s against Facebook’s developer policies, which state:

You must not circumvent our intended limitations on core Facebook features.

The Facebook Connect button is intended to be rendered in FBML, which means it’s only meant to look the way Facebook lets it.

When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used?

Does this answer your question?

I have never used reinterpret_cast, and wonder whether running into a case that needs it isn't a smell of bad design. In the code base I work on dynamic_cast is used a lot. The difference with static_cast is that a dynamic_cast does runtime checking which may (safer) or may not (more overhead) be what you want (see msdn).

Android/Java - Date Difference in days

This is NOT my work, found the answer here. did not want a broken link in the future :).

The key is this line for taking daylight setting into account, ref Full Code.

TimeZone.setDefault(TimeZone.getTimeZone("Europe/London"));

or try passing TimeZone as a parameter to daysBetween() and call setTimeZone() in the sDate and eDate objects.

So here it goes:

public static Calendar getDatePart(Date date){
    Calendar cal = Calendar.getInstance();       // get calendar instance
    cal.setTime(date);      
    cal.set(Calendar.HOUR_OF_DAY, 0);            // set hour to midnight
    cal.set(Calendar.MINUTE, 0);                 // set minute in hour
    cal.set(Calendar.SECOND, 0);                 // set second in minute
    cal.set(Calendar.MILLISECOND, 0);            // set millisecond in second
    
    return cal;                                  // return the date part
}

getDatePart() taken from here

/**
 * This method also assumes endDate >= startDate
**/
public static long daysBetween(Date startDate, Date endDate) {
  Calendar sDate = getDatePart(startDate);
  Calendar eDate = getDatePart(endDate);

  long daysBetween = 0;
  while (sDate.before(eDate)) {
      sDate.add(Calendar.DAY_OF_MONTH, 1);
      daysBetween++;
  }
  return daysBetween;
}

The Nuances: Finding the difference between two dates isn't as straightforward as subtracting the two dates and dividing the result by (24 * 60 * 60 * 1000). Infact, its erroneous!

For example: The difference between the two dates 03/24/2007 and 03/25/2007 should be 1 day; However, using the above method, in the UK, you'll get 0 days!

See for yourself (code below). Going the milliseconds way will lead to rounding off errors and they become most evident once you have a little thing like Daylight Savings Time come into the picture.

Full Code:

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public class DateTest {

public class DateTest {

static SimpleDateFormat sdf = new SimpleDateFormat("dd-MMM-yyyy");

public static void main(String[] args) {

  TimeZone.setDefault(TimeZone.getTimeZone("Europe/London"));

  //diff between these 2 dates should be 1
  Date d1 = new Date("01/01/2007 12:00:00");
  Date d2 = new Date("01/02/2007 12:00:00");

  //diff between these 2 dates should be 1
  Date d3 = new Date("03/24/2007 12:00:00");
  Date d4 = new Date("03/25/2007 12:00:00");

  Calendar cal1 = Calendar.getInstance();cal1.setTime(d1);
  Calendar cal2 = Calendar.getInstance();cal2.setTime(d2);
  Calendar cal3 = Calendar.getInstance();cal3.setTime(d3);
  Calendar cal4 = Calendar.getInstance();cal4.setTime(d4);

  printOutput("Manual   ", d1, d2, calculateDays(d1, d2));
  printOutput("Calendar ", d1, d2, daysBetween(cal1, cal2));
  System.out.println("---");
  printOutput("Manual   ", d3, d4, calculateDays(d3, d4));
  printOutput("Calendar ", d3, d4, daysBetween(cal3, cal4));
}


private static void printOutput(String type, Date d1, Date d2, long result) {
  System.out.println(type+ "- Days between: " + sdf.format(d1)
                    + " and " + sdf.format(d2) + " is: " + result);
}

/** Manual Method - YIELDS INCORRECT RESULTS - DO NOT USE**/
/* This method is used to find the no of days between the given dates */
public static long calculateDays(Date dateEarly, Date dateLater) {
  return (dateLater.getTime() - dateEarly.getTime()) / (24 * 60 * 60 * 1000);
}

/** Using Calendar - THE CORRECT WAY**/
public static long daysBetween(Date startDate, Date endDate) {
  ...
}

OUTPUT:

Manual - Days between: 01-Jan-2007 and 02-Jan-2007 is: 1

Calendar - Days between: 01-Jan-2007 and 02-Jan-2007 is: 1


Manual - Days between: 24-Mar-2007 and 25-Mar-2007 is: 0

Calendar - Days between: 24-Mar-2007 and 25-Mar-2007 is: 1

android.content.res.Resources$NotFoundException: String resource ID #0x0

Change

dateTime.setText(app.getTotalDl());

To

dateTime.setText(String.valueOf(app.getTotalDl()));

There are different versions of setText - one takes a String and one takes an int resource id. If you pass it an integer it will try to look for the corresponding string resource id - which it can't find, which is your error.

I guess app.getTotalDl() returns an int. You need to specifically tell setText to set it to the String value of this int.

setText (int resid) vs setText (CharSequence text)

PHP cURL HTTP CODE return 0

What is the exact contents you are passing into $html_brand?

If it is has an invalid URL syntax, you will very likely get the HTTP code 0.

Setting the default page for ASP.NET (Visual Studio) server configuration

The built-in webserver is hardwired to use Default.aspx as the default page.

The project must have atleast an empty Default.aspx file to overcome the Directory Listing problem for Global.asax.

:)

Once you add that empty file all requests can be handled in one location.

public class Global : System.Web.HttpApplication
{
    protected void Application_BeginRequest(object sender, EventArgs e)
    {
        this.Response.Write("hi@ " + this.Request.Path + "?" + this.Request.QueryString);
        this.Response.StatusCode = 200;
        this.Response.ContentType = "text/plain";

        this.Response.End();
    }
}

How to fix Invalid AES key length?

You can use this code, this code is for AES-256-CBC or you can use it for other AES encryption. Key length error mainly comes in 256-bit encryption.

This error comes due to the encoding or charset name we pass in the SecretKeySpec. Suppose, in my case, I have a key length of 44, but I am not able to encrypt my text using this long key; Java throws me an error of invalid key length. Therefore I pass my key as a BASE64 in the function, and it converts my 44 length key in the 32 bytes, which is must for the 256-bit encryption.

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.MessageDigest;
import java.security.Security;
import java.util.Base64;

public class Encrypt {

    static byte [] arr = {1,2,3,4,5,6,7,8,9};

    // static byte [] arr = new byte[16];

      public static void main(String...args) {
        try {
         //   System.out.println(Cipher.getMaxAllowedKeyLength("AES"));
            Base64.Decoder decoder = Base64.getDecoder();
            // static byte [] arr = new byte[16];
            Security.setProperty("crypto.policy", "unlimited");
            String key = "Your key";
       //     System.out.println("-------" + key);

            String value = "Hey, i am adnan";
            String IV = "0123456789abcdef";
       //     System.out.println(value);
            // log.info(value);
          IvParameterSpec iv = new IvParameterSpec(IV.getBytes());
            //    IvParameterSpec iv = new IvParameterSpec(arr);

        //    System.out.println(key);
            SecretKeySpec skeySpec = new SecretKeySpec(decoder.decode(key), "AES");
         //   System.out.println(skeySpec);
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        //    System.out.println("ddddddddd"+IV);
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
       //     System.out.println(cipher.getIV());

            byte[] encrypted = cipher.doFinal(value.getBytes());
            String encryptedString = Base64.getEncoder().encodeToString(encrypted);

            System.out.println("encrypted string,,,,,,,,,,,,,,,,,,,: " + encryptedString);
            // vars.put("input-1",encryptedString);
            //  log.info("beanshell");
        }catch (Exception e){
            System.out.println(e.getMessage());
        }
    }
}

mysql after insert trigger which updates another table's column

Maybe remove the semi-colon after set because now the where statement doesn't belong to the update statement. Also the idRequest could be a problem, better write BookingRequest.idRequest

Explode PHP string by new line

Here is what worked for me. Tested in PHP 5.6 as well as as PHP 7.0:

    $skuList = str_replace("\\r\\n", "\n", $_POST['skuList']);
    $skuList = str_replace("\\n\\r", "\n", $skuList);

    $skuList = preg_split("/\n/", $skuList);
    print_r($skuList);

Where/How to getIntent().getExtras() in an Android Fragment?

you can still use

String Item = getIntent().getExtras().getString("name");

in the fragment, you just need call getActivity() first:

String Item = getActivity().getIntent().getExtras().getString("name");

This saves you having to write some code.

How to declare an array of objects in C#

I guess GameObject is a reference type. Default for reference types is null => you have an array of nulls.

You need to initialize each member of the array separatedly.

houses[0] = new GameObject(..);

Only then can you access the object without compilation errors.

So you can explicitly initalize the array:

for (int i = 0; i < houses.Length; i++)
{
    houses[i] = new GameObject();
}

or you can change GameObject to value type.

data type not understood

Try:

mmatrix = np.zeros((nrows, ncols))

Since the shape parameter has to be an int or sequence of ints

http://docs.scipy.org/doc/numpy/reference/generated/numpy.zeros.html

Otherwise you are passing ncols to np.zeros as the dtype.

Array inside a JavaScript Object?

In regards to multiple arrays in an object. For instance, you want to record modules for different courses

var course = {
    InfoTech:["Information Systems","Internet Programming","Software Eng"],
    BusComm:["Commercial Law","Accounting","Financial Mng"],
    Tourism:["Travel Destination","Travel Services","Customer Mng"]
};
console.log(course.Tourism[1]);
console.log(course.BusComm);
console.log(course.InfoTech);

Display PNG image as response to jQuery AJAX request

Method 1

You should not make an ajax call, just put the src of the img element as the url of the image.

This would be useful if you use GET instead of POST

<script type="text/javascript" > 

  $(document).ready( function() { 
      $('.div_imagetranscrits').html('<img src="get_image_probes_via_ajax.pl?id_project=xxx" />')
  } );

</script>

Method 2

If you want to POST to that image and do it the way you do (trying to parse the contents of the image on the client side, you could try something like this: http://en.wikipedia.org/wiki/Data_URI_scheme

You'll need to encode the data to base64, then you could put data:[<MIME-type>][;charset=<encoding>][;base64],<data> into the img src

as example:

<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red dot img" />

To encode to base64:

Errors: Data path ".builders['app-shell']" should have required property 'class'

What actually worked for me was to update the application and its dependencies with:

ng update @angular/cli @angular/core

Angular documentation

Creating SVG elements dynamically with javascript inside HTML

To facilitate svg editing you can use an intermediate function:

function getNode(n, v) {
  n = document.createElementNS("http://www.w3.org/2000/svg", n);
  for (var p in v)
    n.setAttributeNS(null, p, v[p]);
  return n
}

Now you can write:

svg.appendChild( getNode('rect', { width:200, height:20, fill:'#ff0000' }) );

Example (with an improved getNode function allowing camelcase for property with dash, eg strokeWidth > stroke-width):

_x000D_
_x000D_
function getNode(n, v) {_x000D_
  n = document.createElementNS("http://www.w3.org/2000/svg", n);_x000D_
  for (var p in v)_x000D_
    n.setAttributeNS(null, p.replace(/[A-Z]/g, function(m, p, o, s) { return "-" + m.toLowerCase(); }), v[p]);_x000D_
  return n_x000D_
}_x000D_
_x000D_
var svg = getNode("svg");_x000D_
document.body.appendChild(svg);_x000D_
_x000D_
var r = getNode('rect', { x: 10, y: 10, width: 100, height: 20, fill:'#ff00ff' });_x000D_
svg.appendChild(r);_x000D_
_x000D_
var r = getNode('rect', { x: 20, y: 40, width: 100, height: 40, rx: 8, ry: 8, fill: 'pink', stroke:'purple', strokeWidth:7 });_x000D_
svg.appendChild(r);
_x000D_
_x000D_
_x000D_

How can I include all JavaScript files in a directory via JavaScript file?

You can't do that in JavaScript, since JS is executed in the browser, not in the server, so it didn't know anything about directories or other server resources.

The best option is using a server side script like the one posted by jellyfishtree.

How do I create my own URL protocol? (e.g. so://...)

For most Microsoft products (Internet Explorer, Office, "open file" dialogs etc) you can register an application to be run when URI with appropriate prefix is opened. This is a part of more common explanation - how to implement your own protocol.

For Mozilla the explanation is here, Java - here.

How to display custom view in ActionBar?

For example, you can define a layout file which contains a EditText element.

<?xml version="1.0" encoding="utf-8"?>
<EditText xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/searchfield"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:inputType="textFilter" >

</EditText> 

you can do

public class MainActivity extends Activity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    ActionBar actionBar = getActionBar();
    // add the custom view to the action bar
    actionBar.setCustomView(R.layout.actionbar_view);
    EditText search = (EditText) actionBar.getCustomView().findViewById(R.id.searchfield);
    search.setOnEditorActionListener(new OnEditorActionListener() {

      @Override
      public boolean onEditorAction(TextView v, int actionId,
          KeyEvent event) {
        Toast.makeText(MainActivity.this, "Search triggered",
            Toast.LENGTH_LONG).show();
        return false;
      }
    });
    actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM
        | ActionBar.DISPLAY_SHOW_HOME);


    }

How do I tell Matplotlib to create a second (new) plot, then later plot on the old one?

One way I found after some struggling is creating a function which gets data_plot matrix, file name and order as parameter to create boxplots from the given data in the ordered figure (different orders = different figures) and save it under the given file_name.

def plotFigure(data_plot,file_name,order):
    fig = plt.figure(order, figsize=(9, 6))
    ax = fig.add_subplot(111)
    bp = ax.boxplot(data_plot)
    fig.savefig(file_name, bbox_inches='tight')
    plt.close()

WebRTC vs Websockets: If WebRTC can do Video, Audio, and Data, why do I need Websockets?

webRTC or websockets? Why not use both.

When building a video/audio/text chat, webRTC is definitely a good choice since it uses peer to peer technology and once the connection is up and running, you do not need to pass the communication via a server (unless using TURN).

When setting up the webRTC communication you have to involve some sort of signaling mechanism. Websockets could be a good choice here, but webRTC is the way to go for the video/audio/text info. Chat rooms is accomplished in the signaling.

But, as you mention, not every browser supports webRTC, so websockets can sometimes be a good fallback for those browsers.

Number of lines in a file in Java

/**
 * Count file rows.
 *
 * @param file file
 * @return file row count
 * @throws IOException
 */
public static long getLineCount(File file) throws IOException {

    try (Stream<String> lines = Files.lines(file.toPath())) {
        return lines.count();
    }
}

Tested on JDK8_u31. But indeed performance is slow compared to this method:

/**
 * Count file rows.
 *
 * @param file file
 * @return file row count
 * @throws IOException
 */
public static long getLineCount(File file) throws IOException {

    try (BufferedInputStream is = new BufferedInputStream(new FileInputStream(file), 1024)) {

        byte[] c = new byte[1024];
        boolean empty = true,
                lastEmpty = false;
        long count = 0;
        int read;
        while ((read = is.read(c)) != -1) {
            for (int i = 0; i < read; i++) {
                if (c[i] == '\n') {
                    count++;
                    lastEmpty = true;
                } else if (lastEmpty) {
                    lastEmpty = false;
                }
            }
            empty = false;
        }

        if (!empty) {
            if (count == 0) {
                count = 1;
            } else if (!lastEmpty) {
                count++;
            }
        }

        return count;
    }
}

Tested and very fast.

How to get item's position in a list?

Try the below:

testlist = [1,2,3,5,3,1,2,1,6]    
position=0
for i in testlist:
   if i == 1:
      print(position)
   position=position+1

Matplotlib make tick labels font size smaller

To specify both font size and rotation at the same time, try this:

plt.xticks(fontsize=14, rotation=90)

R define dimensions of empty data frame

seq_along may help to find out how many rows in your data file and create a data.frame with the desired number of rows

    listdf <- data.frame(ID=seq_along(df),
                              var1=seq_along(df), var2=seq_along(df))

How to uncheck a radio button?

$('#frm input[type="radio":checked]').each(function(){
   $(this).checked = false;  
  });

This is almost good but you missed the [0]

Correct ->> $(this)[0].checked = false;

Angularjs autocomplete from $http

You need to write a controller with ng-change function in scope. In ng-change callback you do a call to server and update completions. Here is a stub (without $http as this is a plunk):

HTML

<!doctype html>
<html ng-app="plunker">
    <head>
        <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.0.5/angular.js"></script>
        <script src="http://angular-ui.github.io/bootstrap/ui-bootstrap-tpls-0.4.0.js"></script>
        <script src="example.js"></script>
        <link href="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/css/bootstrap-combined.min.css" rel="stylesheet">
    </head>
    <body>
        <div class='container-fluid' ng-controller="TypeaheadCtrl">
            <pre>Model: {{selected| json}}</pre>
            <pre>{{states}}</pre>
            <input type="text" ng-change="onedit()" ng-model="selected" typeahead="state for state in states | filter:$viewValue">
        </div>
    </body>
</html>

JS

angular.module('plunker', ['ui.bootstrap']);

function TypeaheadCtrl($scope) {
  $scope.selected = undefined;
  $scope.states = [];

  $scope.onedit = function(){
    $scope.states = [];

    for(var i = 0; i < Math.floor((Math.random()*10)+1); i++){
      var value = "";

      for(var j = 0; j < i; j++){
        value += j;
      }
      $scope.states.push(value);
    }
  }
}

How do I deal with "signed/unsigned mismatch" warnings (C4018)?

I would just do

int pnSize = primeNumber.size();
for (int i = 0; i < pnSize; i++)
    cout << primeNumber[i] << ' ';

jQuery selector for inputs with square brackets in the name attribute

Just separate it with different quotes:

<input name="myName[1][data]" value="myValue">

JQuery:

var value = $('input[name="myName[1][data]"]').val();

Get Absolute URL from Relative path (refactored method)

If you're in the context of an MVC Controller or View you can use the UrlHelper which should be accessible via just Url

Url.Content("~/content/images/myimage.jpg")

Which will be fully expanded to /virtual_directoryname/content/images/myimage.jpg

This can be used in a controller or .cshtml file

Yes it is a little odd that it's called Content but it's meant to be used to get an absolute path to a resource so it makes sense

How can I present a file for download from an MVC controller?

Although standard action results FileContentResult or FileStreamResult may be used for downloading files, for reusability, creating a custom action result might be the best solution.

As an example let's create a custom action result for exporting data to Excel files on the fly for download.

ExcelResult class inherits abstract ActionResult class and overrides the ExecuteResult method.

We are using FastMember package for creating DataTable from IEnumerable object and ClosedXML package for creating Excel file from the DataTable.

public class ExcelResult<T> : ActionResult
{
    private DataTable dataTable;
    private string fileName;

    public ExcelResult(IEnumerable<T> data, string filename, string[] columns)
    {
        this.dataTable = new DataTable();
        using (var reader = ObjectReader.Create(data, columns))
        {
            dataTable.Load(reader);
        }
        this.fileName = filename;
    }

    public override void ExecuteResult(ControllerContext context)
    {
        if (context != null)
        {
            var response = context.HttpContext.Response;
            response.Clear();
            response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
            response.AddHeader("content-disposition", string.Format(@"attachment;filename=""{0}""", fileName));
            using (XLWorkbook wb = new XLWorkbook())
            {
                wb.Worksheets.Add(dataTable, "Sheet1");
                using (MemoryStream stream = new MemoryStream())
                {
                    wb.SaveAs(stream);
                    response.BinaryWrite(stream.ToArray());
                }
            }
        }
    }
}

In the Controller use the custom ExcelResult action result as follows

[HttpGet]
public async Task<ExcelResult<MyViewModel>> ExportToExcel()
{
    var model = new Models.MyDataModel();
    var items = await model.GetItems();
    string[] columns = new string[] { "Column1", "Column2", "Column3" };
    string filename = "mydata.xlsx";
    return new ExcelResult<MyViewModel>(items, filename, columns);
}

Since we are downloading the file using HttpGet, create an empty View without model and empty layout.

Blog post about custom action result for downloading files that are created on the fly:

https://acanozturk.blogspot.com/2019/03/custom-actionresult-for-files-in-aspnet.html

Difference between onStart() and onResume()

Note that there are things that happen between the calls to onStart() and onResume(). Namely, onNewIntent(), which I've painfully found out.

If you are using the SINGLE_TOP flag, and you send some data to your activity, using intent extras, you will be able to access it only in onNewIntent(), which is called after onStart() and before onResume(). So usually, you will take the new (maybe only modified) data from the extras and set it to some class members, or use setIntent() to set the new intent as the original activity intent and process the data in onResume().

'if' statement in jinja2 template

We need to remember that the {% endif %} comes after the {% else %}.

So this is an example:

{% if someTest %}
     <p> Something is True </p>
{% else %}
     <p> Something is False </p>
{% endif %}

SQL Server stored procedure creating temp table and inserting value

A SELECT INTO statement creates the table for you. There is no need for the CREATE TABLE statement before hand.

What is happening is that you create #ivmy_cash_temp1 in your CREATE statement, then the DB tries to create it for you when you do a SELECT INTO. This causes an error as it is trying to create a table that you have already created.

Either eliminate the CREATE TABLE statement or alter your query that fills it to use INSERT INTO SELECT format.

If you need a unique ID added to your new row then it's best to use SELECT INTO... since IDENTITY() only works with this syntax.

How to deselect a selected UITableView cell?

Swift 4:

tableView.deselectRow(at: indexPath, animated: true)

Eclipse jump to closing brace

On the Macintosh, place the cursor after either the opening or closing curly brace } and use the keys: Shift + Command + P.

ASP.NET MVC JsonResult Date Format

Just to expand on casperOne's answer.

The JSON spec does not account for Date values. MS had to make a call, and the path they chose was to exploit a little trick in the javascript representation of strings: the string literal "/" is the same as "\/", and a string literal will never get serialized to "\/" (even "\/" must be mapped to "\\/").

See http://msdn.microsoft.com/en-us/library/bb299886.aspx#intro_to_json_topic2 for a better explanation (scroll down to "From JavaScript Literals to JSON")

One of the sore points of JSON is the lack of a date/time literal. Many people are surprised and disappointed to learn this when they first encounter JSON. The simple explanation (consoling or not) for the absence of a date/time literal is that JavaScript never had one either: The support for date and time values in JavaScript is entirely provided through the Date object. Most applications using JSON as a data format, therefore, generally tend to use either a string or a number to express date and time values. If a string is used, you can generally expect it to be in the ISO 8601 format. If a number is used, instead, then the value is usually taken to mean the number of milliseconds in Universal Coordinated Time (UTC) since epoch, where epoch is defined as midnight January 1, 1970 (UTC). Again, this is a mere convention and not part of the JSON standard. If you are exchanging data with another application, you will need to check its documentation to see how it encodes date and time values within a JSON literal. For example, Microsoft's ASP.NET AJAX uses neither of the described conventions. Rather, it encodes .NET DateTime values as a JSON string, where the content of the string is /Date(ticks)/ and where ticks represents milliseconds since epoch (UTC). So November 29, 1989, 4:55:30 AM, in UTC is encoded as "\/Date(628318530718)\/".

A solution would be to just parse it out:

value = new Date(parseInt(value.replace("/Date(", "").replace(")/",""), 10));

However I've heard that there is a setting somewhere to get the serializer to output DateTime objects with the new Date(xxx) syntax. I'll try to dig that out.


The second parameter of JSON.parse() accepts a reviver function where prescribes how the value originally produced by, before being returned.

Here is an example for date:

var parsed = JSON.parse(data, function(key, value) {
  if (typeof value === 'string') {
    var d = /\/Date\((\d*)\)\//.exec(value);
    return (d) ? new Date(+d[1]) : value;
  }
  return value;
});

See the docs of JSON.parse()

Compiling php with curl, where is curl installed?

If you're going to compile a 64bit version(x86_64) of php use: /usr/lib64/

For architectures (i386 ... i686) use /usr/lib/

I recommend compiling php to the same architecture as apache. As you're using a 64bit linux i asume your apache is also compiled for x86_64.

How to find out mySQL server ip address from phpmyadmin

The SQL query SHOW VARIABLES WHERE Variable_name = 'hostname' will show you the hostname of the MySQL server which you can easily resolve to its IP address.

SHOW VARIABLES WHERE Variable_name = 'port' Will give you the port number.

You can find details about this in MySQL's manual: 12.4.5.41. SHOW VARIABLES Syntax and 5.1.4. Server System Variables

"Parse Error : There is a problem parsing the package" while installing Android application

use it inside build.gradle (Module:app)

minSdkVersion 14
targetSdkVersion 28

This error also comes when Android version is less than minSdkVersion

Restore a postgres backup file using the command line?

You might need to be logged in as postgres in order to have full privileges on databases.

su - postgres
psql -l                      # will list all databases on Postgres cluster

pg_dump/pg_restore

  pg_dump -U username -f backup.dump database_name -Fc 

switch -F specify format of backup file:

  • c will use custom PostgreSQL format which is compressed and results in smallest backup file size
  • d for directory where each file is one table
  • t for TAR archive (bigger than custom format)
  • -h/--host Specifies the host name of the machine on which the server is running
  • -W/--password Force pg_dump to prompt for a password before connecting to a database

restore backup:

   pg_restore -d database_name -U username -C backup.dump

Parameter -C should create database before importing data. If it doesn't work you can always create database eg. with command (as user postgres or other account that has rights to create databases) createdb db_name -O owner

pg_dump/psql

In case that you didn't specify the argument -F default plain text SQL format was used (or with -F p). Then you can't use pg_restore. You can import data with psql.

backup:

pg_dump -U username -f backup.sql database_name

restore:

psql -d database_name -f backup.sql

H.264 file size for 1 hr of HD video

It is whatever size you want it to be, the only thing that changes is quality. If you intend it to be played back on a non-PC device (or a slow PC), you may need to respect a certain profile (standardized set of compression settings that ensure a fixed device can play back the content).

You can see the main H.264 profiles at Wikipedia

While it is highly subjective (and highly dependent on the content being compressed), it is claimed that H.264 can achieve the same quality as DVD MPEG2 using half the bitrate.

Nested ng-repeat

Create a dummy tag that is not going to rendered on the page but it will work as holder for ng-repeat:

<dummyTag ng-repeat="featureItem in item.features">{{featureItem.feature}}</br> </dummyTag>

How to set environment variable for everyone under my linux system?

As well as /etc/profile which others have mentioned, some Linux systems now use a directory /etc/profile.d/; any .sh files in there will be sourced by /etc/profile. It's slightly neater to keep your custom environment stuff in these files than to just edit /etc/profile.

How do I create a simple 'Hello World' module in Magento?

And,

I suggest you to learn about system configuration.

How to Show All Categories on System Configuration Field?

Here I solved with a good example. It working. You can check and learn the flow of code.

There are other too many examples also that you should learn.