Programs & Examples On #Criteria api

This tag is for questions related to the Java Persistence Criteria API (from JPA 2.0) which is used to define queries through the construction of object-based query definition objects, rather than use of the string-based approach of the Java Persistence query language. For questions related to (N)Hibernate Criteria, use the [icriteria] tag.

JPA 2.0, Criteria API, Subqueries, In Expressions

Below is the pseudo-code for using sub-query using Criteria API.

CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
CriteriaQuery<Object> criteriaQuery = criteriaBuilder.createQuery();
Root<EMPLOYEE> from = criteriaQuery.from(EMPLOYEE.class);
Path<Object> path = from.get("compare_field"); // field to map with sub-query
from.fetch("name");
from.fetch("id");
CriteriaQuery<Object> select = criteriaQuery.select(from);

Subquery<PROJECT> subquery = criteriaQuery.subquery(PROJECT.class);
Root fromProject = subquery.from(PROJECT.class);
subquery.select(fromProject.get("requiredColumnName")); // field to map with main-query
subquery.where(criteriaBuilder.and(criteriaBuilder.equal("name",name_value),criteriaBuilder.equal("id",id_value)));

select.where(criteriaBuilder.in(path).value(subquery));

TypedQuery<Object> typedQuery = entityManager.createQuery(select);
List<Object> resultList = typedQuery.getResultList();

Also it definitely needs some modification as I have tried to map it according to your query. Here is a link http://www.ibm.com/developerworks/java/library/j-typesafejpa/ which explains concept nicely.

Using Java generics for JPA findAll() query with WHERE clause

This will work, and if you need where statement you can add it as parameter.

class GenericDAOWithJPA<T, ID extends Serializable> {

.......

public List<T> findAll() {
            return entityManager.createQuery("Select t from " + persistentClass.getSimpleName() + " t").getResultList();
    }
}

JPA Criteria API - How to add JOIN clause (as general sentence as possible)

You don't need to learn JPA. You can use my easy-criteria for JPA2 (https://sourceforge.net/projects/easy-criteria/files/). Here is the example

CriteriaComposer<Pet> petCriteria CriteriaComposer.from(Pet.class).
where(Pet_.type, EQUAL, "Cat").join(Pet_.owner).where(Ower_.name,EQUAL, "foo");

List<Pet> result = CriteriaProcessor.findAllEntiry(petCriteria);

OR

List<Tuple> result =  CriteriaProcessor.findAllTuple(petCriteria);

JPA CriteriaBuilder - How to use "IN" comparison operator

If I understand well, you want to Join ScheduleRequest with User and apply the in clause to the userName property of the entity User.

I'd need to work a bit on this schema. But you can try with this trick, that is much more readable than the code you posted, and avoids the Join part (because it handles the Join logic outside the Criteria Query).

List<String> myList = new ArrayList<String> ();
for (User u : usersList) {
    myList.add(u.getUsername());
}
Expression<String> exp = scheduleRequest.get("createdBy");
Predicate predicate = exp.in(myList);
criteria.where(predicate);

In order to write more type-safe code you could also use Metamodel by replacing this line:

Expression<String> exp = scheduleRequest.get("createdBy");

with this:

Expression<String> exp = scheduleRequest.get(ScheduleRequest_.createdBy);

If it works, then you may try to add the Join logic into the Criteria Query. But right now I can't test it, so I prefer to see if somebody else wants to try.


Not a perfect answer though may be code snippets might help.

public <T> List<T> findListWhereInCondition(Class<T> clazz,
            String conditionColumnName, Serializable... conditionColumnValues) {
        QueryBuilder<T> queryBuilder = new QueryBuilder<T>(clazz);
        addWhereInClause(queryBuilder, conditionColumnName,
                conditionColumnValues);
        queryBuilder.select();
        return queryBuilder.getResultList();

    }


private <T> void addWhereInClause(QueryBuilder<T> queryBuilder,
            String conditionColumnName, Serializable... conditionColumnValues) {

        Path<Object> path = queryBuilder.root.get(conditionColumnName);
        In<Object> in = queryBuilder.criteriaBuilder.in(path);
        for (Serializable conditionColumnValue : conditionColumnValues) {
            in.value(conditionColumnValue);
        }
        queryBuilder.criteriaQuery.where(in);

    }

JPA & Criteria API - Select only specific columns

One of the JPA ways for getting only particular columns is to ask for a Tuple object.

In your case you would need to write something like this:

CriteriaQuery<Tuple> cq = builder.createTupleQuery();
// write the Root, Path elements as usual
Root<EntityClazz> root = cq.from(EntityClazz.class);
cq.multiselect(root.get(EntityClazz_.ID), root.get(EntityClazz_.VERSION));  //using metamodel
List<Tuple> tupleResult = em.createQuery(cq).getResultList();
for (Tuple t : tupleResult) {
    Long id = (Long) t.get(0);
    Long version = (Long) t.get(1);
}

Another approach is possible if you have a class representing the result, like T in your case. T doesn't need to be an Entity class. If T has a constructor like:

public T(Long id, Long version)

then you can use T directly in your CriteriaQuery constructor:

CriteriaQuery<T> cq = builder.createQuery(T.class);
// write the Root, Path elements as usual
Root<EntityClazz> root = cq.from(EntityClazz.class);
cq.multiselect(root.get(EntityClazz_.ID), root.get(EntityClazz_.VERSION));  //using metamodel
List<T> result = em.createQuery(cq).getResultList();

See this link for further reference.

Using a BOOL property

Apple simply recommends declaring an isX getter for stylistic purposes. It doesn't matter whether you customize the getter name or not, as long as you use the dot notation or message notation with the correct name. If you're going to use the dot notation it makes no difference, you still access it by the property name:

@property (nonatomic, assign) BOOL working;

[self setWorking:YES];         // Or self.working = YES;
BOOL working = [self working]; // Or = self.working;

Or

@property (nonatomic, assign, getter=isWorking) BOOL working;

[self setWorking:YES];           // Or self.working = YES;, same as above
BOOL working = [self isWorking]; // Or = self.working;, also same as above

top -c command in linux to filter processes listed based on processname

In htop, you can simply search with

/process-name

How to start an application using android ADB tools?

linux/mac users can also create a script to run an apk with something like the following:

create a file named "adb-run.sh" with these 3 lines:

pkg=$(aapt dump badging $1|awk -F" " '/package/ {print $2}'|awk -F"'" '/name=/ {print $2}')
act=$(aapt dump badging $1|awk -F" " '/launchable-activity/ {print $2}'|awk -F"'" '/name=/ {print $2}')
adb shell am start -n $pkg/$act

then "chmod +x adb-run.sh" to make it executable.

now you can simply:

adb-run.sh myapp.apk

The benefit here is that you don't need to know the package name or launchable activity name. Similarly, you can create "adb-uninstall.sh myapp.apk"

Note: This requires that you have aapt in your path. You can find it under the new build tools folder in the SDK.

How to add header data in XMLHttpRequest when using formdata?

Your error

InvalidStateError: An attempt was made to use an object that is not, or is no longer, usable

appears because you must call setRequestHeader after calling open. Simply move your setRequestHeader line below your open line (but before send):

xmlhttp.open("POST", url);
xmlhttp.setRequestHeader("x-filename", photoId);
xmlhttp.send(formData);

How to make an Android Spinner with initial text "Select One"?

I'd just use a RadioGroup with RadioButtons if you only have three choices, you can make them all unchecked at first.

How to vertically center a container in Bootstrap?

Vertically align center with bootstrap 4

Add this class: d-flex align-items-center to the element

Example

If you had this:

<div class="col-3">

change it to this:

<div class="col-3 d-flex align-items-center>

How to sort an array of objects in Java?

Sometimes you want to sort an array of objects on an arbitrary value. Since compareTo() always uses the same information about the instance, you might want to use a different technique. One way is to use a standard sorting algorithm. Let's say you have an array of books and you want to sort them on their height, which is stored as an int and accessible through the method getHeight(). Here's how you could sort the books in your array. (If you don't want to change the original array, simply make a copy and sort that.)

`int tallest; // the index of tallest book found thus far
 Book temp; // used in the swap
 for(int a = 0; a < booksArray.length - 1; a++) {
   tallest = a; // reset tallest to current index
   // start inner loop at next index
   for(int b = a + 1; b < booksArray.length; b++)
     // check if the book at this index is taller than the
     // tallest found thus far
     if(booksArray[b].getHeight() > booksArray[tallest].getHeight())
       tallest = b;
   // once inner loop is complete, swap the tallest book found with
   // the one at the current index of the outer loop
   temp = booksArray[a];
   booksArray[a] = booksArray[tallest];
   booksArray[tallest] = temp;
 }`

When this code is done, the array of Book object will be sorted by height in descending order--an interior designer's dream!

How to request Location Permission at runtime

check this code from MainActivity

 // Check location permission is granted - if it is, start
// the service, otherwise request the permission
fun checkOrAskLocationPermission(callback: () -> Unit) {
    // Check GPS is enabled
    val lm = getSystemService(Context.LOCATION_SERVICE) as LocationManager
    if (!lm.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
        Toast.makeText(this, "Please enable location services", Toast.LENGTH_SHORT).show()
        buildAlertMessageNoGps(this)
        return
    }

    // Check location permission is granted - if it is, start
    // the service, otherwise request the permission
    val permission = ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
    if (permission == PackageManager.PERMISSION_GRANTED) {
        callback.invoke()
    } else {
        // callback will be inside the activity's onRequestPermissionsResult(
        ActivityCompat.requestPermissions(
            this,
            arrayOf(Manifest.permission.ACCESS_FINE_LOCATION),
            PERMISSIONS_REQUEST
        )
    }
}

plus

   override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults)
    if (requestCode == PERMISSIONS_REQUEST) {
        if (grantResults[0] == PackageManager.PERMISSION_GRANTED){
              // Permission ok. Do work.
         }
    }
}

plus

 fun buildAlertMessageNoGps(context: Context) {
    val builder = AlertDialog.Builder(context);
    builder.setMessage("Your GPS is disabled. Do you want to enable it?")
        .setCancelable(false)
        .setPositiveButton("Yes") { _, _ -> context.startActivity(Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS)) }
        .setNegativeButton("No") { dialog, _ -> dialog.cancel(); }
    val alert = builder.create();
    alert.show();
}

usage

checkOrAskLocationPermission() {
            // Permission ok. Do work.
        }

How do I automatically update a timestamp in PostgreSQL

To populate the column during insert, use a DEFAULT value:

CREATE TABLE users (
  id serial not null,
  firstname varchar(100),
  middlename varchar(100),
  lastname varchar(100),
  email varchar(200),
  timestamp timestamp default current_timestamp
)

Note that the value for that column can explicitly be overwritten by supplying a value in the INSERT statement. If you want to prevent that you do need a trigger.

You also need a trigger if you need to update that column whenever the row is updated (as mentioned by E.J. Brennan)

Note that using reserved words for column names is usually not a good idea. You should find a different name than timestamp

Testing javascript with Mocha - how can I use console.log to debug a test?

I had an issue with node.exe programs like test output with mocha.

In my case, I solved it by removing some default "node.exe" alias.

I'm using Git Bash for Windows(2.29.2) and some default aliases are set from /etc/profile.d/aliases.sh,

  # show me alias related to 'node'
  $ alias|grep node
  alias node='winpty node.exe'`

To remove the alias, update aliases.sh or simply do

unalias node

I don't know why winpty has this side effect on console.info buffered output but with a direct node.exe use, I've no more stdout issue.

Finding the average of an array using JS

The MacGyver way,just for lulz

_x000D_
_x000D_
var a = [80, 77, 88, 95, 68];_x000D_
_x000D_
console.log(eval(a.join('+'))/a.length)
_x000D_
_x000D_
_x000D_

Can an AWS Lambda function call another

You should chain your Lambda functions via SNS. This approach provides good performance, latency and scalability for minimal effort.

Your first Lambda publishes messages to your SNS Topic and the second Lambda is subscribed to this topic. As soon as messages arrive in the topic, second Lambda gets executed with the message as it's input parameter.

See Invoking Lambda functions using Amazon SNS notifications.

You can also use this approach to Invoke cross-account Lambda functions via SNS.

Messages Using Command prompt in Windows 7

"net send" is a command using a background service called "messenger". This service has been removed from Windows 7. ie You cannot use 'net send' on Vista nor Win7 / Win8.

Pity though , I loved using it.

There is alternatives, but that requires you to download and install software on each pc you want to use, this software runs as background services, and i would advise one to be very very very very careful of using these kind of software as they can potentially cause seriously damage one's system or impair the systems securities.

winsent innocenti / winsent messenger

****This command is risky because of what is stated above***

How to add/update child entities when updating a parent entity in EF

For VB.NET developers Use this generic sub to mark the child state, easy to use

Notes:

  • PromatCon: the entity object
  • amList: is the child list that you want to add or modify
  • rList: is the child list that you want to remove
updatechild(objCas.ECC_Decision, PromatCon.ECC_Decision.Where(Function(c) c.rid = objCas.rid And Not objCas.ECC_Decision.Select(Function(x) x.dcid).Contains(c.dcid)).toList)
Sub updatechild(Of Ety)(amList As ICollection(Of Ety), rList As ICollection(Of Ety))
        If amList IsNot Nothing Then
            For Each obj In amList
                Dim x = PromatCon.Entry(obj).GetDatabaseValues()
                If x Is Nothing Then
                    PromatCon.Entry(obj).State = EntityState.Added
                Else
                    PromatCon.Entry(obj).State = EntityState.Modified
                End If
            Next
        End If

        If rList IsNot Nothing Then
            For Each obj In rList.ToList
                PromatCon.Entry(obj).State = EntityState.Deleted
            Next
        End If
End Sub
PromatCon.SaveChanges()

How do I mock an autowired @Value field in Spring with Mockito?

I used the below code and it worked for me:

@InjectMocks
private ClassABC classABC;

@Before
public void setUp() {
    ReflectionTestUtils.setField(classABC, "constantFromConfigFile", 3);
}

Reference: https://www.jeejava.com/mock-an-autowired-value-field-in-spring-with-junit-mockito/

Why would one use nested classes in C++?

Nested classes are cool for hiding implementation details.

List:

class List
{
    public:
        List(): head(nullptr), tail(nullptr) {}
    private:
        class Node
        {
              public:
                  int   data;
                  Node* next;
                  Node* prev;
        };
    private:
        Node*     head;
        Node*     tail;
};

Here I don't want to expose Node as other people may decide to use the class and that would hinder me from updating my class as anything exposed is part of the public API and must be maintained forever. By making the class private, I not only hide the implementation I am also saying this is mine and I may change it at any time so you can not use it.

Look at std::list or std::map they all contain hidden classes (or do they?). The point is they may or may not, but because the implementation is private and hidden the builders of the STL were able to update the code without affecting how you used the code, or leaving a lot of old baggage laying around the STL because they need to maintain backwards compatibility with some fool who decided they wanted to use the Node class that was hidden inside list.

Bootstrap 3.0 Sliding Menu from left

Probably late but here is a plugin that can do the job : http://multi-level-push-menu.make.rs/

Also v2 can use mobile gesture such as swipe ;)

How to print current date on python3?

The following seems to work:

import datetime
print (datetime.datetime.now().strftime("%y"))

The datetime.data object that it wants is on the "left" of the dot rather than the right. You need an instance of the datetime to call the method on, which you get through now()

How to check if object has any properties in JavaScript?

What about making a simple function?

function isEmptyObject(obj) {
  for(var prop in obj) {
    if (Object.prototype.hasOwnProperty.call(obj, prop)) {
      return false;
    }
  }
  return true;
}

isEmptyObject({}); // true
isEmptyObject({foo:'bar'});  // false

The hasOwnProperty method call directly on the Object.prototype is only to add little more safety, imagine the following using a normal obj.hasOwnProperty(...) call:

isEmptyObject({hasOwnProperty:'boom'});  // false

Note: (for the future) The above method relies on the for...in statement, and this statement iterates only over enumerable properties, in the currently most widely implemented ECMAScript Standard (3rd edition) the programmer doesn't have any way to create non-enumerable properties.

However this has changed now with ECMAScript 5th Edition, and we are able to create non-enumerable, non-writable or non-deletable properties, so the above method can fail, e.g.:

var obj = {};
Object.defineProperty(obj, 'test', { value: 'testVal', 
  enumerable: false,
  writable: true,
  configurable: true
});
isEmptyObject(obj); // true, wrong!!
obj.hasOwnProperty('test'); // true, the property exist!!

An ECMAScript 5 solution to this problem would be:

function isEmptyObject(obj) {
  return Object.getOwnPropertyNames(obj).length === 0;
}

The Object.getOwnPropertyNames method returns an Array containing the names of all the own properties of an object, enumerable or not, this method is being implemented now by browser vendors, it's already on the Chrome 5 Beta and the latest WebKit Nightly Builds.

Object.defineProperty is also available on those browsers and latest Firefox 3.7 Alpha releases.

How to set a CMake option() at command line

Delete the CMakeCache.txt file and try this:

cmake -G %1 -DBUILD_SHARED_LIBS=ON -DBUILD_STATIC_LIBS=ON -DBUILD_TESTS=ON ..

You have to enter all your command-line definitions before including the path.

How to get the file-path of the currently executing javascript code

Regardless of whether its a script, a html file (for a frame, for example), css file, image, whatever, if you dont specify a server/domain the path of the html doc will be the default, so you could do, for example,

<script type=text/javascript src='/dir/jsfile.js'></script>

or

<script type=text/javascript src='../../scripts/jsfile.js'></script>

If you don't provide the server/domain, the path will be relative to either the path of the page or script of the main document's path

Excel how to find values in 1 column exist in the range of values in another

Use the formula by tigeravatar:

=COUNTIF($B$2:$B$5,A2)>0 – tigeravatar Aug 28 '13 at 14:50

as conditional formatting. Highlight column A. Choose conditional formatting by forumula. Enter the formula (above) - this finds values in col B that are also in A. Choose a format (I like to use FILL and a bold color).

To find all of those values, highlight col A. Data > Filter and choose Filter by color.

How do I detect the Python version at runtime?

To make the scripts compatible with Python2 and 3 i use :

from sys import version_info
if version_info[0] < 3:
    from __future__ import print_function

Update query with PDO and MySQL

Your update syntax is incorrect. Please check Update Syntax for the correct syntax.

$sql = "UPDATE `access_users` set `contact_first_name` = :firstname,  `contact_surname` = :surname, `contact_email` = :email, `telephone` = :telephone";

Add and remove multiple classes in jQuery

You can separate multiple classes with the space:

$("p").addClass("myClass yourClass");

http://api.jquery.com/addClass/

How to send email to multiple recipients using python smtplib?

import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

def sender(recipients): 

    body = 'Your email content here'
    msg = MIMEMultipart()

    msg['Subject'] = 'Email Subject'
    msg['From'] = '[email protected]'
    msg['To'] = (', ').join(recipients.split(','))

    msg.attach(MIMEText(body,'plain'))

    server = smtplib.SMTP('smtp.gmail.com', 587)
    server.starttls()
    server.login('[email protected]', 'yourpassword')
    server.send_message(msg)
    server.quit()

if __name__ == '__main__':
    sender('[email protected],[email protected]')

It only worked for me with send_message function and using the join function in the list whith recipients, python 3.6.

PHPMailer character encoding issues

I work myself this way

  $mail->FromName = utf8_decode($_POST['name']);

http://php.net/manual/en/function.utf8-decode.php

CSS way to horizontally align table

Simple. IE6 and above will happily center your table with "margin: 0 auto;" if only the page renders in "standards" mode. To make this happen you need a valid doctype declaration, such as

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">

or

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

True, IE5.5 and below will still refuse to center the table but perhaps you can live with that, especially if the page is still functional with the table left aligned. I think by now users of IE5.5 and below are fairly used to some odd looking websites - but you still need to ensure that those visual glitches don't render your site unusable.

Happy coding!

EDIT: Sorry, I should perhaps point out that you do not have to have a "strict" doctype to get IE6 and up into "standards" rendering mode. I realised it might seem that way from the doctype examples I posted above. For example, this doctype declaration will of course work equally:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

Python convert set to string and vice versa

If you do not need the serialized text to be human readable, you can use pickle.

import pickle

s = set([1,2,3])

serialized_s = pickle.dumps(s)
print "serialized:"
print serialized_s

deserialized_s = pickle.loads(serialized_s)
print "deserialized:"
print deserialized_s

Result:

serialized:
c__builtin__
set
p0
((lp1
I1
aI2
aI3
atp2
Rp3
.
deserialized:
set([1, 2, 3])

How to initialize java.util.date to empty

Instance of java.util.Date stores a date. So how can you store nothing in it or have it empty? It can only store references to instances of java.util.Date. If you make it null means that it is not referring any instance of java.util.Date.

You have tried date2=""; what you mean to do by this statement you want to reference the instance of String to a variable that is suppose to store java.util.Date. This is not possible as Java is Strongly Typed Language.

Edit

After seeing the comment posted to the answer of LastFreeNickname

I am having a form that the date textbox should be by default blank in the textbox, however while submitting the data if the user didn't enter anything, it should accept it

I would suggest you could check if the textbox is empty. And if it is empty, then you could store default date in your variable or current date or may be assign it null as shown below:

if(textBox.getText() == null || textBox.getText().equals(""){
    date2 = null; // For Null;
    // date2 = new Date(); For Current Date
    // date2 = new Date(0); For Default Date
}

Also I can assume since you are asking user to enter a date in a TextBox, you are using a DateFormat to parse the text that is entered in the TextBox. If this is the case you could simply call the dateFormat.parse() which throws a ParseException if the format in which the date was written is incorrect or is empty string. Here in the catch block you could put the above statements as show below:

try{
    date2 = dateFormat.parse(textBox.getText());
}catch(ParseException e){
    date2 = null; // For Null;
    // date2 = new Date(); For Current Date
    // date2 = new Date(0); For Default Date
}

Return multiple values from a function, sub or type?

A function returns one value, but it can "output" any number of values. A sample code:

Function Test (ByVal Input1 As Integer, ByVal Input2 As Integer, _
ByRef Output1 As Integer, ByRef Output2 As Integer) As Integer

  Output1 = Input1 + Input2
  Output2 = Input1 - Input2
  Test = Output1 + Output2

End Function

Sub Test2()

  Dim Ret As Integer, Input1 As Integer, Input2 As Integer, _
  Output1 As integer, Output2 As Integer
  Input1 = 1
  Input2 = 2
  Ret = Test(Input1, Input2, Output1, Output2)
  Sheet1.Range("A1") = Ret     ' 2
  Sheet1.Range("A2") = Output1 ' 3
  Sheet1.Range("A3") = Output2 '-1

End Sub

How to run a script file remotely using SSH

I don't know if it's possible to run it just like that.

I usually first copy it with scp and then log in to run it.

scp foo.sh user@host:~
ssh user@host
./foo.sh

Jquery Date picker Default Date

$( ".selector" ).datepicker({ defaultDate: null });

and return empty string from backend

How to remove any URL within a string in Python

The following regular expression in Python works well for detecting URL(s) in the text:

source_text = '''
text1
text2
http://url.com/bla1/blah1/
text3
text4
http://url.com/bla2/blah2/
text5
text6    '''

import re
url_reg  = r'[a-z]*[:.]+\S+'
result   = re.sub(url_reg, '', source_text)
print(result)

Output:

text1
text2

text3
text4

text5
text6

Difference between Dictionary and Hashtable

Simply, Dictionary<TKey,TValue> is a generic type, allowing:

  • static typing (and compile-time verification)
  • use without boxing

If you are .NET 2.0 or above, you should prefer Dictionary<TKey,TValue> (and the other generic collections)

A subtle but important difference is that Hashtable supports multiple reader threads with a single writer thread, while Dictionary offers no thread safety. If you need thread safety with a generic dictionary, you must implement your own synchronization or (in .NET 4.0) use ConcurrentDictionary<TKey, TValue>.

How to secure an ASP.NET Web API

in continuation to @ Cuong Le's answer , my approach to prevent replay attack would be

// Encrypt the Unix Time at Client side using the shared private key(or user's password)

// Send it as part of request header to server(WEB API)

// Decrypt the Unix Time at Server(WEB API) using the shared private key(or user's password)

// Check the time difference between the Client's Unix Time and Server's Unix Time, should not be greater than x sec

// if User ID/Hash Password are correct and the decrypted UnixTime is within x sec of server time then it is a valid request

Jackson: how to prevent field serialization

You can mark it as @JsonIgnore.

With 1.9, you can add @JsonIgnore for getter, @JsonProperty for setter, to make it deserialize but not serialize.

Could not load NIB in bundle

I ran into the same problem. In my case the nib name was "MyViewController.xib" and I renamed it to "MyView.xib". This got rid of the error.

I was also moving a project from XCode 3 to 4.2. Changing the Path type did not matter.

How do I programmatically click a link with javascript?

document.getElementById('yourLinkID').click();

MySQL Insert query doesn't work with WHERE clause

It depends on the situation INSERT can actually have a where clause.

For example if you are matching values from a form.

Consider INSERT INTO Users(name,email,weight, desiredWeight) VALUES (fred,[email protected],160,145) WHERE name != fred AND email != [email protected]

Makes sense doesn't it?

How to see query history in SQL Server Management Studio

[Since this question will likely be closed as a duplicate.]

If SQL Server hasn't been restarted (and the plan hasn't been evicted, etc.), you may be able to find the query in the plan cache.

SELECT t.[text]
FROM sys.dm_exec_cached_plans AS p
CROSS APPLY sys.dm_exec_sql_text(p.plan_handle) AS t
WHERE t.[text] LIKE N'%something unique about your query%';

If you lost the file because Management Studio crashed, you might be able to find recovery files here:

C:\Users\<you>\Documents\SQL Server Management Studio\Backup Files\

Otherwise you'll need to use something else going forward to help you save your query history, like SSMS Tools Pack as mentioned in Ed Harper's answer - though it isn't free in SQL Server 2012+. Or you can set up some lightweight tracing filtered on your login or host name (but please use a server-side trace, not Profiler, for this).


As @Nenad-Zivkovic commented, it might be helpful to join on sys.dm_exec_query_stats and order by last_execution_time:

SELECT t.[text], s.last_execution_time
FROM sys.dm_exec_cached_plans AS p
INNER JOIN sys.dm_exec_query_stats AS s
   ON p.plan_handle = s.plan_handle
CROSS APPLY sys.dm_exec_sql_text(p.plan_handle) AS t
WHERE t.[text] LIKE N'%something unique about your query%'
ORDER BY s.last_execution_time DESC;

Determining whether an object is a member of a collection in VBA

In your specific case (TableDefs) iterating over the collection and checking the Name is a good approach. This is OK because the key for the collection (Name) is a property of the class in the collection.

But in the general case of VBA collections, the key will not necessarily be part of the object in the collection (e.g. you could be using a Collection as a dictionary, with a key that has nothing to do with the object in the collection). In this case, you have no choice but to try accessing the item and catching the error.

StringBuilder vs String concatenation in toString() in Java

For simple strings like that I prefer to use

"string".concat("string").concat("string");

In order, I would say the preferred method of constructing a string is using StringBuilder, String#concat(), then the overloaded + operator. StringBuilder is a significant performance increase when working large strings just like using the + operator is a large decrease in performance (exponentially large decrease as the String size increases). The one problem with using .concat() is that it can throw NullPointerExceptions.

Set multiple system properties Java command line

There's nothing on the Documentation that mentions about anything like that.

Here's a quote:

-Dproperty=value Set a system property value. If value is a string that contains spaces, you must enclose the string in double quotes:

java -Dfoo="some string" SomeClass

Excel VBA - Range.Copy transpose paste

Worksheets("Sheet1").Range("A1:A5").Copy
Worksheets("Sheet2").Range("A1").PasteSpecial Transpose:=True

Oracle date difference to get number of years

For Oracle SQL Developer I was able to calculate the difference in years using the below line of SQL. This was to get Years that were within 0 to 10 years difference. You can do a case like shown in some of the other responses to handle your ifs as well. Happy Coding!

TRUNC((MONTHS_BETWEEN(<DATE_ONE>, <DATE_TWO>) * 31) / 365) > 0 and TRUNC((MONTHS_BETWEEN(<DATE_ONE>, <DATE_TWO>) * 31) / 365) < 10

Angular 5 Button Submit On Enter Key Press

Try to use keyup.enter but make sure to use it inside your input tag

<input
  matInput
  placeholder="enter key word"
  [(ngModel)]="keyword"
  (keyup.enter)="addToKeywords()"
/>

What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?

remap is an option that makes mappings work recursively. By default it is on and I'd recommend you leave it that way. The rest are mapping commands, described below:

:map and :noremap are recursive and non-recursive versions of the various mapping commands. For example, if we run:

:map j gg           (moves cursor to first line)
:map Q j            (moves cursor to first line)
:noremap W j        (moves cursor down one line)

Then:

  • j will be mapped to gg.
  • Q will also be mapped to gg, because j will be expanded for the recursive mapping.
  • W will be mapped to j (and not to gg) because j will not be expanded for the non-recursive mapping.

Now remember that Vim is a modal editor. It has a normal mode, visual mode and other modes.

For each of these sets of mappings, there is a mapping that works in normal, visual, select and operator modes (:map and :noremap), one that works in normal mode (:nmap and :nnoremap), one in visual mode (:vmap and :vnoremap) and so on.

For more guidance on this, see:

:help :map
:help :noremap
:help recursive_mapping
:help :map-modes

Multiline strings in VB.NET

To me that is the most annoying thing about VB as a language. Seriously, i once wrote the string in a file and wrote code something along the lines of:

Dim s as String = file_get_contents("filename.txt")

just so i could test the query directly on SQL server if i need to.

My current method is to use a stored procedure on the SQL Server and just call that so i can pass in parameters to the query, etc

Bootstrap 3.0: How to have text and input on same line?

just give mother of div "class="col-lg-12""

<div class="form-group">
<div class="row">
    <div class="col-xs-3">
        <label for="class_type"><h2><span class=" label label-primary">Class Type</span></h2></label>
    </div>
    <div class="col-xs-2">
        <select name="class_type" id="class_type" class="  form-control input-lg" style="width:200px" autocomplete="off">
            <option >Economy</option>
            <option >Premium Economy</option>
            <option >Club World</option>
            <option >First Class</option>
        </select>
    </div>
 </div>

it will be

<div class="form-group">
<div class="col-lg-12">
  <div class="row">
    <div class="col-xs-3">
        <label for="class_type"><h2><span class=" label label-primary">Class Type</span></h2></label>
    </div>
    <div class="col-xs-2">
        <select name="class_type" id="class_type" class="  form-control input-lg" style="width:200px" autocomplete="off">
            <option >Economy</option>
            <option >Premium Economy</option>
            <option >Club World</option>
            <option >First Class</option>
        </select>
    </div>
</div>
</div>

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;
}

Disable sorting on last column when using jQuery DataTables

use this link http://datatables.net/ref#bSortable

$(document).ready( function() {
   $('#example').dataTable( {
      "aoColumnDefs": [{ "bSortable": false, "aTargets": [ 0 ] }]
    } );
} );

Is there any native DLL export functions viewer?

dumpbin from the Visual Studio command prompt:

dumpbin /exports csp.dll

Example of output:

Microsoft (R) COFF/PE Dumper Version 10.00.30319.01
Copyright (C) Microsoft Corporation.  All rights reserved.


Dump of file csp.dll

File Type: DLL

  Section contains the following exports for CSP.dll

    00000000 characteristics
    3B1D0B77 time date stamp Tue Jun 05 12:40:23 2001
        0.00 version
           1 ordinal base
          25 number of functions
          25 number of names

    ordinal hint RVA      name

          1    0 00001470 CPAcquireContext
          2    1 000014B0 CPCreateHash
          3    2 00001520 CPDecrypt
          4    3 000014B0 CPDeriveKey
          5    4 00001590 CPDestroyHash
          6    5 00001590 CPDestroyKey
          7    6 00001560 CPEncrypt
          8    7 00001520 CPExportKey
          9    8 00001490 CPGenKey
         10    9 000015B0 CPGenRandom
         11    A 000014D0 CPGetHashParam
         12    B 000014D0 CPGetKeyParam
         13    C 00001500 CPGetProvParam
         14    D 000015C0 CPGetUserKey
         15    E 00001580 CPHashData
         16    F 000014F0 CPHashSessionKey
         17   10 00001540 CPImportKey
         18   11 00001590 CPReleaseContext
         19   12 00001580 CPSetHashParam
         20   13 00001580 CPSetKeyParam
         21   14 000014F0 CPSetProvParam
         22   15 00001520 CPSignHash
         23   16 000015A0 CPVerifySignature
         24   17 00001060 DllRegisterServer
         25   18 00001000 DllUnregisterServer

  Summary

        1000 .data
        1000 .rdata
        1000 .reloc
        1000 .rsrc
        1000 .text

Disable firefox same origin policy

In about:config add content.cors.disable (empty string).

Exposing the current state name with ui router

I wrapped around $state around $timeout and it worked for me.

For example,

(function() {
  'use strict';

  angular
    .module('app')
    .controller('BodyController', BodyController);

  BodyController.$inject = ['$state', '$timeout'];

  /* @ngInject */
  function BodyController($state, $timeout) {
    $timeout(function(){
      console.log($state.current);
    });

  }
})();

How to select distinct query using symfony2 doctrine query builder?

Just open your repository file and add this new function, then call it inside your controller:

 public function distinctCategories(){
        return $this->createQueryBuilder('cc')
        ->where('cc.contenttype = :type')
        ->setParameter('type', 'blogarticle')
        ->groupBy('cc.blogarticle')
        ->getQuery()
        ->getResult()
        ;
    }

Then within your controller:

public function index(YourRepository $repo)
{
    $distinctCategories = $repo->distinctCategories();


    return $this->render('your_twig_file.html.twig', [
        'distinctCategories' => $distinctCategories
    ]);
}

Good luck!

Configuring Hibernate logging using Log4j XML config file?

You can configure your log4j file with the category tag like this (with a console appender for the example):

<appender name="console" class="org.apache.log4j.ConsoleAppender">
    <layout class="org.apache.log4j.PatternLayout">
        <param name="ConversionPattern" value="%d{yy-MM-dd HH:mm:ss} %p %c - %m%n" />
    </layout>
</appender>
<category name="org.hibernate">
    <priority value="WARN" />
</category>
<root>
    <priority value="INFO" />
    <appender-ref ref="console" />
</root>

So every warning, error or fatal message from hibernate will be displayed, nothing more. Also, your code and library code will be in info level (so info, warn, error and fatal)

To change log level of a library, just add a category, for example, to desactive spring info log:

<category name="org.springframework">
    <priority value="WARN" />
</category>

Or with another appender, break the additivity (additivity default value is true)

<category name="org.springframework" additivity="false">
    <priority value="WARN" />
    <appender-ref ref="anotherAppender" />
</category>

And if you don't want that hibernate log every query, set the hibernate property show_sql to false.

How to convert answer into two decimal point

If you have a Decimal or similar numeric type, you can use:

Math.Round(myNumber, 2)

EDIT: So, in your case, it would be:

Public Class Form1
  Private Sub btncalc_Click(ByVal sender As System.Object,
                            ByVal e As System.EventArgs) Handles btncalc.Click
    txtA.Text = Math.Round((Val(txtD.Text) / Val(txtC.Text) * Val(txtF.Text) / Val(txtE.Text)), 2)
    txtB.Text = Math.Round((Val(txtA.Text) * 1000 / Val(txtG.Text)), 2)
  End Sub
End Class

Pretty print in MongoDB shell as default

Give a try to Mongo-hacker(node module), it alway prints pretty. https://github.com/TylerBrock/mongo-hacker

More it enhances mongo shell (supports only ver>2.4, current ver is 3.0), like

  • Colorization
  • Additional shell commands (count documents/count docs/etc)
  • API Additions (db.collection.find({ ... }).last(), db.collection.find({ ... }).reverse(), etc)
  • Aggregation Framework

I am using for while in production env, no problems yet.

Display Last Saved Date on worksheet

This might be an alternative solution. Paste the following code into the new module:

Public Function ModDate()
ModDate = 
Format(FileDateTime(ThisWorkbook.FullName), "m/d/yy h:n ampm") 
End Function

Before saving your module, make sure to save your Excel file as Excel Macro-Enabled Workbook.

Paste the following code into the cell where you want to display the last modification time:

=ModDate()

I'd also like to recommend an alternative to Excel allowing you to add creation and last modification time easily. Feel free to check on RowShare and this article I wrote: https://www.rowshare.com/blog/en/2018/01/10/Displaying-Last-Modification-Time-in-Excel

Extract the filename from a path

Using the BaseName in Get-ChildItem displays the name of the file and and using Name displays the file name with the extension.

$filepath = Get-ChildItem "E:\Test\Basic-English-Grammar-1.pdf"

$filepath.BaseName

Basic-English-Grammar-1

$filepath.Name

Basic-English-Grammar-1.pdf

How to split strings into text and number?

>>> r = re.compile("([a-zA-Z]+)([0-9]+)")
>>> m = r.match("foobar12345")
>>> m.group(1)
'foobar'
>>> m.group(2)
'12345'

So, if you have a list of strings with that format:

import re
r = re.compile("([a-zA-Z]+)([0-9]+)")
strings = ['foofo21', 'bar432', 'foobar12345']
print [r.match(string).groups() for string in strings]

Output:

[('foofo', '21'), ('bar', '432'), ('foobar', '12345')]

Hibernate Group by Criteria Object

If you have to do group by using hibernate criteria use projections.groupPropery like the following,

@Autowired
private SessionFactory sessionFactory;
Criteria crit = sessionFactory.getCurrentSession().createCriteria(studentModel.class);
crit.setProjection(Projections.projectionList()
            .add(Projections.groupProperty("studentName").as("name"))
List result = crit.setResultTransformer(Criteria.ALIAS_TO_ENTITY_MAP).list(); 
return result;  

Tesseract OCR simple example

In my case I had all these worked except for the correct character recognition.

But you need to consider these few things:

  • Use correct tessnet2 library
  • use correct tessdata language version
  • tessdata should be somewhere out of your application folder where you can put in full path in the init parameter. use ocr.Init(@"c:\tessdata", "eng", true);
  • Debugging will cause you headache. Then you need to update your app.config use this. (I can't put the xml code here. give me your email i will email it to you)

hope that this helps

How to handle "Uncaught (in promise) DOMException: play() failed because the user didn't interact with the document first." on Desktop with Chrome 66?

I encountered a similar error with while attempting to play an audio file. At first, it was working, then it stopped working when I started using ChangeDetector's markForCheck method in the same function to trigger a re-render when a promise resolves (I had an issue with view rendering).

When I changed the markForCheck to detectChanges it started working again. I really can't explain what happened, I just thought of dropping this here, perhaps it would help someone.

How to add to an existing hash in Ruby

hash {}
hash[:a] = 'a'
hash[:b] = 'b'
hash = {:a => 'a' , :b = > b}

You might get your key and value from user input, so you can use Ruby .to_sym can convert a string to a symbol, and .to_i will convert a string to an integer.
For example:

movies ={}
movie = gets.chomp
rating = gets.chomp
movies[movie.to_sym] = rating.to_int
# movie will convert to a symbol as a key in our hash, and 
# rating will be an integer as a value.

Align text in a table header

Try:

text-align: center;

You may be familiar with the HTML align attribute (which has been discontinued as of HTML 5). The align attribute could be used with tags such as

<table>, <td>, and <img> 

to specify the alignment of these elements. This attribute allowed you to align elements horizontally. HTML also has/had a valign attribute for aligning elements vertically. This has also been discontinued from HTML5.

These attributes were discontinued in favor of using CSS to set the alignment of HTML elements.

There isn't actually a CSS align or CSS valign property. Instead, CSS has the text-align which applies to inline content of block-level elements, and vertical-align property which applies to inline level and table cells.

How do I use su to execute the rest of the bash script as that user?

The trick is to use "sudo" command instead of "su"

You may need to add this

username1 ALL=(username2) NOPASSWD: /path/to/svn

to your /etc/sudoers file

and change your script to:

sudo -u username2 -H sh -c "cd /home/$USERNAME/$PROJECT; svn update" 

Where username2 is the user you want to run the SVN command as and username1 is the user running the script.

If you need multiple users to run this script, use a %groupname instead of the username1

How do I change db schema to dbo

Way to do it for an individual thing:

alter schema dbo transfer jonathan.MovieData

List all indexes on ElasticSearch server?

If you're working in scala, a way to do this and use Future's is to create a RequestExecutor, then use the IndicesStatsRequestBuilder and the administrative client to submit your request.

import org.elasticsearch.action.{ ActionRequestBuilder, ActionListener, ActionResponse }
import scala.concurrent.{ Future, Promise, blocking }

/** Convenice wrapper for creating RequestExecutors */
object RequestExecutor {
    def apply[T <: ActionResponse](): RequestExecutor[T] = {
        new RequestExecutor[T]
    }
}

/** Wrapper to convert an ActionResponse into a scala Future
 *
 *  @see http://chris-zen.github.io/software/2015/05/10/elasticsearch-with-scala-and-akka.html
 */
class RequestExecutor[T <: ActionResponse] extends ActionListener[T] {
    private val promise = Promise[T]()

    def onResponse(response: T) {
        promise.success(response)
    }

    def onFailure(e: Throwable) {
        promise.failure(e)
    }

    def execute[RB <: ActionRequestBuilder[_, T, _, _]](request: RB): Future[T] = {
        blocking {
            request.execute(this)
            promise.future
        }
    }
}

The executor is lifted from this blog post which is definitely a good read if you're trying to query ES programmatically and not through curl. One you have this you can create a list of all indexes pretty easily like so:

def totalCountsByIndexName(): Future[List[(String, Long)]] = {
    import scala.collection.JavaConverters._
    val statsRequestBuider = new IndicesStatsRequestBuilder(client.admin().indices())
    val futureStatResponse = RequestExecutor[IndicesStatsResponse].execute(statsRequestBuider)
    futureStatResponse.map { indicesStatsResponse =>
        indicesStatsResponse.getIndices().asScala.map {
            case (k, indexStats) => {
                val indexName = indexStats.getIndex()
                val totalCount = indexStats.getTotal().getDocs().getCount()
                    (indexName, totalCount)
                }
        }.toList
    }
}

client is an instance of Client which can be a node or a transport client, whichever suits your needs. You'll also need to have an implicit ExecutionContext in scope for this request. If you try to compile this code without it then you'll get a warning from the scala compiler on how to get that if you don't have one imported already.

I needed the document count, but if you really only need the names of the indices you can pull them from the keys of the map instead of from the IndexStats:

indicesStatsResponse.getIndices().keySet()

This question shows up when you're searching for how to do this even if you're trying to do this programmatically, so I hope this helps anyone looking to do this in scala/java. Otherwise, curl users can just do as the top answer says and use

curl http://localhost:9200/_aliases

error: command 'gcc' failed with exit status 1 while installing eventlet

sudo apt install gcc

It works for PyCharm on Ubuntu 20.10.

How do I find the width & height of a terminal window?

  • tput cols tells you the number of columns.
  • tput lines tells you the number of rows.

'DataFrame' object has no attribute 'sort'

Pandas Sorting 101

sort has been replaced in v0.20 by DataFrame.sort_values and DataFrame.sort_index. Aside from this, we also have argsort.

Here are some common use cases in sorting, and how to solve them using the sorting functions in the current API. First, the setup.

# Setup
np.random.seed(0)
df = pd.DataFrame({'A': list('accab'), 'B': np.random.choice(10, 5)})    
df                                                                                                                                        
   A  B
0  a  7
1  c  9
2  c  3
3  a  5
4  b  2

Sort by Single Column

For example, to sort df by column "A", use sort_values with a single column name:

df.sort_values(by='A')

   A  B
0  a  7
3  a  5
4  b  2
1  c  9
2  c  3

If you need a fresh RangeIndex, use DataFrame.reset_index.

Sort by Multiple Columns

For example, to sort by both col "A" and "B" in df, you can pass a list to sort_values:

df.sort_values(by=['A', 'B'])

   A  B
3  a  5
0  a  7
4  b  2
2  c  3
1  c  9

Sort By DataFrame Index

df2 = df.sample(frac=1)
df2

   A  B
1  c  9
0  a  7
2  c  3
3  a  5
4  b  2

You can do this using sort_index:

df2.sort_index()

   A  B
0  a  7
1  c  9
2  c  3
3  a  5
4  b  2

df.equals(df2)                                                                                                                            
# False
df.equals(df2.sort_index())                                                                                                               
# True

Here are some comparable methods with their performance:

%timeit df2.sort_index()                                                                                                                  
%timeit df2.iloc[df2.index.argsort()]                                                                                                     
%timeit df2.reindex(np.sort(df2.index))                                                                                                   

605 µs ± 13.6 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
610 µs ± 24.2 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
581 µs ± 7.63 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)

Sort by List of Indices

For example,

idx = df2.index.argsort()
idx
# array([0, 7, 2, 3, 9, 4, 5, 6, 8, 1])

This "sorting" problem is actually a simple indexing problem. Just passing integer labels to iloc will do.

df.iloc[idx]

   A  B
1  c  9
0  a  7
2  c  3
3  a  5
4  b  2

What is ANSI format?

I remember when "ANSI" text referred to the pseudo VT-100 escape codes usable in DOS through the ANSI.SYS driver to alter the flow of streaming text.... Probably not what you are referring to but if it is see http://en.wikipedia.org/wiki/ANSI_escape_code

What does git push -u mean?

When you push a new branch the first time use: >git push -u origin

After that, you can just type a shorter command: >git push

The first-time -u option created a persistent upstream tracking branch with your local branch.

How to get query params from url in Angular 2?

To send query params

import { Router } from '@angular/router';
this.router.navigate([ '/your-route' ], { queryParams: { key: va1, keyN: valN } });

To receive query params

import { ActivatedRoute } from '@angular/router';
this.activatedRoute.queryParams.subscribe(params => {
    let value_1 = params['key'];
    let value_N = params['keyN'];
});

Official source

CORS header 'Access-Control-Allow-Origin' missing

You have to modify your server side code, as given below

public class CorsResponseFilter implements ContainerResponseFilter {
@Override
public void filter(ContainerRequestContext requestContext,   ContainerResponseContext responseContext)
    throws IOException {
        responseContext.getHeaders().add("Access-Control-Allow-Origin","*");
        responseContext.getHeaders().add("Access-Control-Allow-Methods", "GET, POST, DELETE, PUT");

  }
}

jQuery - Uncaught RangeError: Maximum call stack size exceeded

Your calls are made recursively which pushes functions on to the stack infinitely that causes max call stack exceeded error due to recursive behavior. Instead try using setTimeout which is a callback.

Also based on your markup your selector is wrong. it should be #advisersDiv

Demo

function fadeIn() {
    $('#pulseDiv').find('div#advisersDiv').delay(400).addClass("pulse");
    setTimeout(fadeOut,1); //<-- Provide any delay here
};

function fadeOut() {
    $('#pulseDiv').find('div#advisersDiv').delay(400).removeClass("pulse");
    setTimeout(fadeIn,1);//<-- Provide any delay here
};
fadeIn();

How to replace a hash key with another key

Answering exactly what was asked:

hash = {"_id"=>"4de7140772f8be03da000018"}
hash.transform_keys { |key| key[1..] }
# => {"id"=>"4de7140772f8be03da000018"}

The method transform_keys exists in the Hash class since Ruby version 2.5.

https://blog.bigbinary.com/2018/01/09/ruby-2-5-adds-hash-transform_keys-method.html

How to change the session timeout in PHP?

You can override values in php.ini from your PHP code using ini_set().

Convert String to SecureString

You can follow this:

string password = "test";
SecureString sec_pass = new SecureString();
Array.ForEach(password.ToArray(), sec_pass.AppendChar);
sec_pass.MakeReadOnly();

http to https through .htaccess

There are better and more secure ways to make sure that all your traffic goes over https. For example setting up two virtual hosts and redirecting all traffic from your http to your https host. Read more on this in this answer here on security.stackexchange.com.

With setting up a virtual host for redirecting you can send a 301 status (redirect permanently) so the browser understands that all the following requests should be sent to the https server where it was redirected to. Hence no further http requests will be made after the first redirect response.

You should also carefully check the given answers because with the wrong rewrite rules set you might loose the query params from your incoming requests.

Environment variable in Jenkins Pipeline

You can access the same environment variables from groovy using the same names (e.g. JOB_NAME or env.JOB_NAME).

From the documentation:

Environment variables are accessible from Groovy code as env.VARNAME or simply as VARNAME. You can write to such properties as well (only using the env. prefix):

env.MYTOOL_VERSION = '1.33'
node {
  sh '/usr/local/mytool-$MYTOOL_VERSION/bin/start'
}

These definitions will also be available via the REST API during the build or after its completion, and from upstream Pipeline builds using the build step.

For the rest of the documentation, click the "Pipeline Syntax" link from any Pipeline job enter image description here

Binding ItemsSource of a ComboBoxColumn in WPF DataGrid

I realize this question is over a year old, but I just stumbled across it in dealing with a similar problem and thought I would share another potential solution in case it might help a future traveler (or myself, when I forget this later and find myself flopping around on StackOverflow between screams and throwings of the nearest object on my desk).

In my case I was able to get the effect I wanted by using a DataGridTemplateColumn instead of a DataGridComboBoxColumn, a la the following snippet. [caveat: I'm using .NET 4.0, and what I've been reading leads me to believe the DataGrid has done a lot of evolving, so YMMV if using earlier version]

<DataGridTemplateColumn Header="Identifier_TEMPLATED">
    <DataGridTemplateColumn.CellEditingTemplate>
        <DataTemplate>
            <ComboBox IsEditable="False" 
                Text="{Binding ComponentIdentifier,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
                ItemsSource="{Binding Path=ApplicableIdentifiers, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}" />
        </DataTemplate>
    </DataGridTemplateColumn.CellEditingTemplate>
    <DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
            <TextBlock Text="{Binding ComponentIdentifier}" />
        </DataTemplate>
    </DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>

codeigniter model error: Undefined property

function user() { 

       parent::Model(); 

} 

=> class name is User, construct name is User.

function User() { 

       parent::Model(); 

} 

Chain-calling parent initialisers in python

The way you are doing it is indeed the recommended one (for Python 2.x).

The issue of whether the class is passed explicitly to super is a matter of style rather than functionality. Passing the class to super fits in with Python's philosophy of "explicit is better than implicit".

Android Studio Gradle Already disposed Module

I also face this problem sometimes. Click on gradle console in bottom bar of android studio, at right side. It will show the exact error in logs. My problem was that I had compile SDK 22 and imported appcomact library was of sdk 23.

What is the dual table in Oracle?

From Wikipedia

History

The DUAL table was created by Chuck Weiss of Oracle corporation to provide a table for joining in internal views:

I created the DUAL table as an underlying object in the Oracle Data Dictionary. It was never meant to be seen itself, but instead used inside a view that was expected to be queried. The idea was that you could do a JOIN to the DUAL table and create two rows in the result for every one row in your table. Then, by using GROUP BY, the resulting join could be summarized to show the amount of storage for the DATA extent and for the INDEX extent(s). The name, DUAL, seemed apt for the process of creating a pair of rows from just one. 1

It may not be obvious from the above, but the original DUAL table had two rows in it (hence its name). Nowadays it only has one row.

Optimization

DUAL was originally a table and the database engine would perform disk IO on the table when selecting from DUAL. This disk IO was usually logical IO (not involving physical disk access) as the disk blocks were usually already cached in memory. This resulted in a large amount of logical IO against the DUAL table.

Later versions of the Oracle database have been optimized and the database no longer performs physical or logical IO on the DUAL table even though the DUAL table still actually exists.

Python regex to match dates

I built my solution on top of @aditya Prakash appraoch:

 print(re.search("^([1-9]|0[1-9]|1[0-9]|2[0-9]|3[0-1])(\.|-|/)([1-9]|0[1-9]|1[0-2])(\.|-|/)([0-9][0-9]|19[0-9][0-9]|20[0-9][0-9])$|^([0-9][0-9]|19[0-9][0-9]|20[0-9][0-9])(\.|-|/)([1-9]|0[1-9]|1[0-2])(\.|-|/)([1-9]|0[1-9]|1[0-9]|2[0-9]|3[0-1])$",'01/01/2018'))

The first part (^([1-9]|0[1-9]|1[0-9]|2[0-9]|3[0-1])(\.|-|/)([1-9]|0[1-9]|1[0-2])(\.|-|/)([0-9][0-9]|19[0-9][0-9]|20[0-9][0-9])$) can handle the following formats:

  • 01.10.2019
  • 1.1.2019
  • 1.1.19
  • 12/03/2020
  • 01.05.1950

The second part (^([0-9][0-9]|19[0-9][0-9]|20[0-9][0-9])(\.|-|/)([1-9]|0[1-9]|1[0-2])(\.|-|/)([1-9]|0[1-9]|1[0-9]|2[0-9]|3[0-1])$) can basically do the same, but in inverse order, where the year comes first, followed by month, and then day.

  • 2020/02/12

As delimiters it allows ., /, -. As years it allows everything from 1900-2099, also giving only two numbers is fine.

If you have suggestions for improvement please let me know in the comments, so I can update the answer.

View tabular file such as CSV from command line

Using TxtSushi you can do:

csvtopretty filename.csv | less -S

How to use the COLLATE in a JOIN in SQL Server?

As a general rule, you can use Database_Default collation so you don't need to figure out which one to use. However, I strongly suggest reading Simons Liew's excellent article Understanding the COLLATE DATABASE_DEFAULT clause in SQL Server

SELECT *
  FROM [FAEB].[dbo].[ExportaComisiones] AS f
  JOIN [zCredifiel].[dbo].[optPerson] AS p
  ON (p.vTreasuryId = f.RFC) COLLATE Database_Default 

Calculating distance between two points, using latitude longitude?

Slightly upgraded answer from @David George:

public static double distance(double lat1, double lat2, double lon1,
                              double lon2, double el1, double el2) {

    final int R = 6371; // Radius of the earth

    double latDistance = Math.toRadians(lat2 - lat1);
    double lonDistance = Math.toRadians(lon2 - lon1);
    double a = Math.sin(latDistance / 2) * Math.sin(latDistance / 2)
            + Math.cos(Math.toRadians(lat1)) * Math.cos(Math.toRadians(lat2))
            * Math.sin(lonDistance / 2) * Math.sin(lonDistance / 2);
    double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    double distance = R * c * 1000; // convert to meters

    double height = el1 - el2;

    distance = Math.pow(distance, 2) + Math.pow(height, 2);

    return Math.sqrt(distance);
}

public static double distanceBetweenLocations(Location l1, Location l2) {
    if(l1.hasAltitude() && l2.hasAltitude()) {
        return distance(l1.getLatitude(), l2.getLatitude(), l1.getLongitude(), l2.getLongitude(), l1.getAltitude(), l2.getAltitude());
    }
    return l1.distanceTo(l2);
}

distance function is the same, but I've created I small wrapper function, which takes 2 Location objects. Thanks to this, I only use distance function if both of locations actually have altitude, because sometimes they don't. And it can lead to strange results (if location doesn't know its altitude 0 will be returned). In this case, I fall back to classic distanceTo function.

SSIS package creating Hresult: 0x80004005 Description: "Login timeout expired" error

I had a similar error..This might be due to two reasons. a) If you have used variables, re-evaluate the expressions in which variables are used and make sure the expression is evaluated without errors. b) If you are deleting the excel sheet and creating excel sheet on the fly in your package.

Convert Text to Uppercase while typing in Text box

There is a specific property for this. It is called CharacterCasing and you could set it to Upper

  TextBox1.CharacterCasing = CharacterCasing.Upper;

In ASP.NET you could try to add this to your textbox style

  style="text-transform:uppercase;"

You could find an example here: http://www.w3schools.com/cssref/pr_text_text-transform.asp

How to fix "The ConnectionString property has not been initialized"

The connection string is not in AppSettings.

What you're looking for is in:

System.Configuration.ConfigurationManager.ConnectionStrings["MyDB"]...

Convert file to byte array and vice versa

I think you misunderstood what the java.io.File class really represents. It is just a representation of the file on your system, i.e. its name, its path etc.

Did you even look at the Javadoc for the java.io.File class? Have a look here If you check the fields it has or the methods or constructor arguments, you immediately get the hint that all it is, is a representation of the URL/path.

Oracle provides quite an extensive tutorial in their Java File I/O tutorial, with the latest NIO.2 functionality too.

With NIO.2 you can read it in one line using java.nio.file.Files.readAllBytes().

Similarly you can use java.nio.file.Files.write() to write all bytes in your byte array.

UPDATE

Since the question is tagged Android, the more conventional way is to wrap the FileInputStream in a BufferedInputStream and then wrap that in a ByteArrayInputStream. That will allow you to read the contents in a byte[]. Similarly the counterparts to them exist for the OutputStream.

How to stretch the background image to fill a div

Try something like this:

div {
    background-image: url(../img/picture1.jpg);
    height: 30em;
    background-repeat: no-repeat;
    width: 100%;
    background-position: center;
}

LF will be replaced by CRLF in git - What is that and is it important?

If you want, you can deactivate this feature in your git core config using

git config core.autocrlf false

But it would be better to just get rid of the warnings using

git config core.autocrlf true

Animation CSS3: display + opacity

I used this to achieve it. They fade on hover but take no space when hidden, perfect!

.child {
    height: 0px;
    opacity: 0;
    visibility: hidden;
    transition: all .5s ease-in-out;
}

.parent:hover .child {
    height: auto;
    opacity: 1;
    visibility: visible;
}

Error reading JObject from JsonReader. Current JsonReader item is not an object: StartArray. Path

I ran into a very similar problem with my Xamarin Windows Phone 8.1 app. The reason JObject.Parse(json) would not work for me was because my Json had a beginning "[" and an ending "]". In order to make it work, I had to remove those two characters. From your example, it looks like you might have the same issue.

jsonResult = jsonResult.TrimStart(new char[] { '[' }).TrimEnd(new char[] { ']' });

I was then able to use the JObject.Parse(jsonResult) and everything worked.

How to check if array element is null to avoid NullPointerException in Java

The given code works for me. Notice that someArray[i] is always null since you have not initialized the second dimension of the array.

Better way to sort array in descending order

class Program
{
    private static int[] table;

    static void Main(string[] args)
    {
        int[] ints = new int[] { 6, 2, 5, 99, 55 };

       table = ints.OrderByDescending(x => x).ToArray();

        foreach (var item in table)
        {
            Console.WriteLine(item);
        }

    }

How to solve SyntaxError on autogenerated manage.py?

I was experiencing the same but this was solved by running with specific python 3.6 as below:

python3.6 manage.py runserver

How to list npm user-installed packages?

As a shorthand, you can run:

npm ls -g --depth=0

Remove blank attributes from an Object in Javascript

If you use eslint and want to avoid tripping the the no-param-reassign rule, you can use Object.assign in conjunction with .reduce and a computed property name for a fairly elegant ES6 solution:

const queryParams = { a: 'a', b: 'b', c: 'c', d: undefined, e: null, f: '', g: 0 };
const cleanParams = Object.keys(queryParams) 
  .filter(key => queryParams[key] != null)
  .reduce((acc, key) => Object.assign(acc, { [key]: queryParams[key] }), {});
// { a: 'a', b: 'b', c: 'c', f: '', g: 0 }

Select box arrow style

for any1 using ie8 and dont want to use a plugin i've made something inspired by Rohit Azad and Bacotasan's blog, i just added a span using JS to show the selected value.

the html:

<div class="styled-select">
   <select>
      <option>Here is the first option</option>
      <option>The second option</option>
   </select>
   <span>Here is the first option</span>
</div>

the css (i used only an arrow for BG but you could put a full image and drop the positioning):

.styled-select div
{
    display:inline-block;
    border: 1px solid darkgray;
    width:100px;
    background:url("/Style Library/Nifgashim/Images/drop_arrrow.png") no-repeat 10px 10px;
    position:relative;
}

.styled-select div select
{
    height: 30px;
    width: 100px;
    font-size:14px;
    font-family:ariel;

    -moz-opacity: 0.00;
    opacity: .00;
    filter: alpha(opacity=00);
}

.styled-select div span
{
    position: absolute;
    right: 10px;
    top: 6px;
    z-index: -5;
}

the js:

$(".styled-select select").change(function(e){
     $(".styled-select span").html($(".styled-select select").val());
});

Don't change link color when a link is clicked

I think this suits perfect for any color you have:

a {
    color: inherit;
}

What is the origin of foo and bar?

tl;dr

  • "Foo" and "bar" as metasyntactic variables were popularised by MIT and DEC, the first references are in work on LISP and PDP-1 and Project MAC from 1964 onwards.

  • Many of these people were in MIT's Tech Model Railroad Club, where we find the first documented use of "foo" in tech circles in 1959 (and a variant in 1958).

  • Both "foo" and "bar" (and even "baz") were well known in popular culture, especially from Smokey Stover and Pogo comics, which will have been read by many TMRC members.

  • Also, it seems likely the military FUBAR contributed to their popularity.


The use of lone "foo" as a nonsense word is pretty well documented in popular culture in the early 20th century, as is the military FUBAR. (Some background reading: FOLDOC FOLDOC Jargon File Jargon File Wikipedia RFC3092)


OK, so let's find some references.

STOP PRESS! After posting this answer, I discovered this perfect article about "foo" in the Friday 14th January 1938 edition of The Tech ("MIT's oldest and largest newspaper & the first newspaper published on the web"), Volume LVII. No. 57, Price Three Cents:

On Foo-ism

The Lounger thinks that this business of Foo-ism has been carried too far by its misguided proponents, and does hereby and forthwith take his stand against its abuse. It may be that there's no foo like an old foo, and we're it, but anyway, a foo and his money are some party. (Voice from the bleachers- "Don't be foo-lish!")

As an expletive, of course, "foo!" has a definite and probably irreplaceable position in our language, although we fear that the excessive use to which it is currently subjected may well result in its falling into an early (and, alas, a dark) oblivion. We say alas because proper use of the word may result in such happy incidents as the following.

It was an 8.50 Thermodynamics lecture by Professor Slater in Room 6-120. The professor, having covered the front side of the blackboard, set the handle that operates the lift mechanism, turning meanwhile to the class to continue his discussion. The front board slowly, majestically, lifted itself, revealing the board behind it, and on that board, writ large, the symbols that spelled "FOO"!

The Tech newspaper, a year earlier, the Letter to the Editor, September 1937:

By the time the train has reached the station the neophytes are so filled with the stories of the glory of Phi Omicron Omicron, usually referred to as Foo, that they are easy prey.

...

It is not that I mind having lost my first four sons to the Grand and Universal Brotherhood of Phi Omicron Omicron, but I do wish that my fifth son, my baby, should at least be warned in advance.

Hopefully yours,

Indignant Mother of Five.

And The Tech in December 1938:

General trend of thought might be best interpreted from the remarks made at the end of the ballots. One vote said, '"I don't think what I do is any of Pulver's business," while another merely added a curt "Foo."


The first documented "foo" in tech circles is probably 1959's Dictionary of the TMRC Language:

FOO: the sacred syllable (FOO MANI PADME HUM); to be spoken only when under inspiration to commune with the Deity. Our first obligation is to keep the Foo Counters turning.

These are explained at FOLDOC. The dictionary's compiler Pete Samson said in 2005:

Use of this word at TMRC antedates my coming there. A foo counter could simply have randomly flashing lights, or could be a real counter with an obscure input.

And from 1996's Jargon File 4.0.0:

Earlier versions of this lexicon derived 'baz' as a Stanford corruption of bar. However, Pete Samson (compiler of the TMRC lexicon) reports it was already current when he joined TMRC in 1958. He says "It came from "Pogo". Albert the Alligator, when vexed or outraged, would shout 'Bazz Fazz!' or 'Rowrbazzle!' The club layout was said to model the (mythical) New England counties of Rowrfolk and Bassex (Rowrbazzle mingled with (Norfolk/Suffolk/Middlesex/Essex)."

A year before the TMRC dictionary, 1958's MIT Voo Doo Gazette ("Humor suplement of the MIT Deans' office") (PDF) mentions Foocom, in "The Laws of Murphy and Finagle" by John Banzhaf (an electrical engineering student):

Further research under a joint Foocom and Anarcom grant expanded the law to be all embracing and universally applicable: If anything can go wrong, it will!

Also 1964's MIT Voo Doo (PDF) references the TMRC usage:

Yes! I want to be an instant success and snow customers. Send me a degree in: ...

  • Foo Counters

  • Foo Jung


Let's find "foo", "bar" and "foobar" published in code examples.

So, Jargon File 4.4.7 says of "foobar":

Probably originally propagated through DECsystem manuals by Digital Equipment Corporation (DEC) in 1960s and early 1970s; confirmed sightings there go back to 1972.

The first published reference I can find is from February 1964, but written in June 1963, The Programming Language LISP: its Operation and Applications by Information International, Inc., with many authors, but including Timothy P. Hart and Michael Levin:

Thus, since "FOO" is a name for itself, "COMITRIN" will treat both "FOO" and "(FOO)" in exactly the same way.

Also includes other metasyntactic variables such as: FOO CROCK GLITCH / POOT TOOR / ON YOU / SNAP CRACKLE POP / X Y Z

I expect this is much the same as this next reference of "foo" from MIT's Project MAC in January 1964's AIM-064, or LISP Exercises by Timothy P. Hart and Michael Levin:

car[((FOO . CROCK) . GLITCH)]

It shares many other metasyntactic variables like: CHI / BOSTON NEW YORK / SPINACH BUTTER STEAK / FOO CROCK GLITCH / POOT TOOP / TOOT TOOT / ISTHISATRIVIALEXCERCISE / PLOOP FLOT TOP / SNAP CRACKLE POP / ONE TWO THREE / PLANE SUB THRESHER

For both "foo" and "bar" together, the earliest reference I could find is from MIT's Project MAC in June 1966's AIM-098, or PDP-6 LISP by none other than Peter Samson:

EXPLODE, like PRIN1, inserts slashes, so (EXPLODE (QUOTE FOO/ BAR)) PRIN1's as (F O O // / B A R) or PRINC's as (F O O / B A R).


Some more recallations.

@Walter Mitty recalled on this site in 2008:

I second the jargon file regarding Foo Bar. I can trace it back at least to 1963, and PDP-1 serial number 2, which was on the second floor of Building 26 at MIT. Foo and Foo Bar were used there, and after 1964 at the PDP-6 room at project MAC.

John V. Everett recalls in 1996:

When I joined DEC in 1966, foobar was already being commonly used as a throw-away file name. I believe fubar became foobar because the PDP-6 supported six character names, although I always assumed the term migrated to DEC from MIT. There were many MIT types at DEC in those days, some of whom had worked with the 7090/7094 CTSS. Since the 709x was also a 36 bit machine, foobar may have been used as a common file name there.

Foo and bar were also commonly used as file extensions. Since the text editors of the day operated on an input file and produced an output file, it was common to edit from a .foo file to a .bar file, and back again.

It was also common to use foo to fill a buffer when editing with TECO. The text string to exactly fill one disk block was IFOO$HXA127GA$$. Almost all of the PDP-6/10 programmers I worked with used this same command string.

Daniel P. B. Smith in 1998:

Dick Gruen had a device in his dorm room, the usual assemblage of B-battery, resistors, capacitors, and NE-2 neon tubes, which he called a "foo counter." This would have been circa 1964 or so.

Robert Schuldenfrei in 1996:

The use of FOO and BAR as example variable names goes back at least to 1964 and the IBM 7070. This too may be older, but that is where I first saw it. This was in Assembler. What would be the FORTRAN integer equivalent? IFOO and IBAR?

Paul M. Wexelblat in 1992:

The earliest PDP-1 Assembler used two characters for symbols (18 bit machine) programmers always left a few words as patch space to fix problems. (Jump to patch space, do new code, jump back) That space conventionally was named FU: which stood for Fxxx Up, the place where you fixed Fxxx Ups. When spoken, it was known as FU space. Later Assemblers ( e.g. MIDAS allowed three char tags so FU became FOO, and as ALL PDP-1 programmers will tell you that was FOO space.

Bruce B. Reynolds in 1996:

On the IBM side of FOO(FU)BAR is the use of the BAR side as Base Address Register; in the middle 1970's CICS programmers had to worry out the various xxxBARs...I think one of those was FRACTBAR...

Here's a straight IBM "BAR" from 1955.


Other early references:


I haven't been able to find any references to foo bar as "inverted foo signal" as suggested in RFC3092 and elsewhere.

Here are a some of even earlier F00s but I think they're coincidences/false positives:

Best way to create unique token in Rails?

If you want something that will be unique you can use something like this:

string = (Digest::MD5.hexdigest "#{ActiveSupport::SecureRandom.hex(10)}-#{DateTime.now.to_s}")

however this will generate string of 32 characters.

There is however other way:

require 'base64'

def after_create
update_attributes!(:token => Base64::encode64(id.to_s))
end

for example for id like 10000, generated token would be like "MTAwMDA=" (and you can easily decode it for id, just make

Base64::decode64(string)

Getting request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource

In case of Request to a REST Service:

You need to allow the CORS (cross origin sharing of resources) on the endpoint of your REST Service with Spring annotation:

@CrossOrigin(origins = "http://localhost:8080")

Very good tutorial: https://spring.io/guides/gs/rest-service-cors/

How to delete only the content of file in python

You can do this:

def deleteContent(pfile):
    fn=pfile.name 
    pfile.close()
    return open(fn,'w')

How to compare datetime with only date in SQL Server

Of-course this is an old thread but to make it complete.

From SQL 2008 you can use DATE datatype so you can simply do:

SELECT CONVERT(DATE,GETDATE())

OR

Select * from [User] U
where  CONVERT(DATE,U.DateCreated) = '2014-02-07' 

How can I use Html.Action?

Another case is http redirection. If your page redirects http requests to https, then may be your partial view tries to redirect by itself.

It causes same problem again. For this problem, you can reorganize your .net error pages or iis error pages configuration.

Just make sure you are redirecting requests to right error or not found page and make sure this error page contains non problematic partial. If your page supports only https, do not forward requests to error page without using https, if error page contains partial, this partials tries to redirect seperately from requested url, it causes problem.

java.lang.ClassCastException

According to the documentation:

Thrown to indicate that the code has attempted to cast an Object to a subclass of which it is not an instance. For example, the following code generates a ClassCastException:

Object x = new Integer(0);
System.out.println((String)x); 

prevent property from being serialized in web API

For some reason [IgnoreDataMember] does not always work for me, and I sometimes get StackOverflowException (or similar). So instead (or in addition) i've started using a pattern looking something like this when POSTing in Objects to my API:

[Route("api/myroute")]
[AcceptVerbs("POST")]
public IHttpActionResult PostMyObject(JObject myObject)
{
    MyObject myObjectConverted = myObject.ToObject<MyObject>();

    //Do some stuff with the object

    return Ok(myObjectConverted);
}

So basically i pass in an JObject and convert it after it has been recieved to aviod problems caused by the built-in serializer that sometimes cause an infinite loop while parsing the objects.

If someone know a reason that this is in any way a bad idea, please let me know.

It may be worth noting that it is the following code for an EntityFramework Class-property that causes the problem (If two classes refer to each-other):

[Serializable]
public partial class MyObject
{
   [IgnoreDataMember]
   public MyOtherObject MyOtherObject => MyOtherObject.GetById(MyOtherObjectId);
}

[Serializable]
public partial class MyOtherObject
{
   [IgnoreDataMember]
   public List<MyObject> MyObjects => MyObject.GetByMyOtherObjectId(Id);
}

env: node: No such file or directory in mac

I got such a problem after I upgraded my node version with brew. To fix the problem

1)run $brew doctor to check out if it is successfully installed or not 2) In case you missed clearing any node-related file before, such error log might pop up:

Warning: You have unlinked kegs in your Cellar Leaving kegs unlinked can lead to build-trouble and cause brews that depend on those kegs to fail to run properly once built. node

3) Now you are recommended to run brew link command to delete the original node-related files and overwrite new files - $ brew link node.

And that's it - everything works again !!!

Waiting for another flutter command to release the startup lock

I also faced same issue i followed the best and the easiest way

Environment : Windows

IDE : Android Studio

Tools>flutter(last option)> select flutter clean

after flutter clean finished you all set and good to go.

Mongoose limit/offset and count query

After having to tackle this issue myself, I would like to build upon user854301's answer.

Mongoose ^4.13.8 I was able to use a function called toConstructor() which allowed me to avoid building the query multiple times when filters are applied. I know this function is available in older versions too but you'll have to check the Mongoose docs to confirm this.

The following uses Bluebird promises:

let schema = Query.find({ name: 'bloggs', age: { $gt: 30 } });

// save the query as a 'template'
let query = schema.toConstructor();

return Promise.join(
    schema.count().exec(),
    query().limit(limit).skip(skip).exec(),

    function (total, data) {
        return { data: data, total: total }
    }
);

Now the count query will return the total records it matched and the data returned will be a subset of the total records.

Please note the () around query() which constructs the query.

Is there any way to set environment variables in Visual Studio Code?

In the VSCode launch.json you can use "env" and configure all your environment variables there:

{
    "version": "0.2.0",
    "configurations": [
        {           
            "env": {
                "NODE_ENV": "development",
                "port":"1337"
            },
            ...
        }
    ]
}

get original element from ng-click

You need $event.currentTarget instead of $event.target.

How do I set combobox read-only or user cannot write in a combo box only can select the given items?

Just change the DropDownStyle to DropDownList. Or if you want it completely read only you can set Enabled = false, or if you don't like the look of that I sometimes have two controls, one readonly textbox and one combobox and then hide the combo and show the textbox if it should be completely readonly and vice versa.

How to change progress bar's progress color in Android

For my indeterminate progressbar (spinner) I just set a color filter on the drawable. Works great and just one line.

Example where setting color to red:

ProgressBar spinner = new android.widget.ProgressBar(
                context,
                null,
                android.R.attr.progressBarStyle);

spinner.getIndeterminateDrawable().setColorFilter(0xFFFF0000, android.graphics.PorterDuff.Mode.MULTIPLY);

enter image description here

How can I show a hidden div when a select option is selected?

Check this code. It awesome code for hide div using select item.

HTML

<select name="name" id="cboOptions" onchange="showDiv('div',this)" class="form-control" >
    <option value="1">YES</option>
    <option value="2">NO</option>
</select>

<div id="div1" style="display:block;">
    <input type="text" id="customerName" class="form-control" placeholder="Type Customer Name...">
    <input type="text" style="margin-top: 3px;" id="customerAddress" class="form-control" placeholder="Type Customer Address...">
    <input type="text" style="margin-top: 3px;" id="customerMobile" class="form-control" placeholder="Type Customer Mobile...">
</div>
<div id="div2" style="display:none;">
    <input type="text" list="cars" id="customerID" class="form-control" placeholder="Type Customer Name...">
    <datalist id="cars">
        <option>Value 1</option>
        <option>Value 2</option>
        <option>Value 3</option>
        <option>Value 4</option>
    </datalist>
</div>

JS

<script>
    function showDiv(prefix,chooser) 
    {
            for(var i=0;i<chooser.options.length;i++) 
            {
                var div = document.getElementById(prefix+chooser.options[i].value);
                div.style.display = 'none';
            }

            var selectedOption = (chooser.options[chooser.selectedIndex].value);

            if(selectedOption == "1")
            {
                displayDiv(prefix,"1");
            }
            if(selectedOption == "2")
            {
                displayDiv(prefix,"2");
            }
    }

    function displayDiv(prefix,suffix) 
    {
            var div = document.getElementById(prefix+suffix);
            div.style.display = 'block';
    }
</script>

Is there a Google Keep API?

No there's not and developers still don't know why google doesn't pay attention to this request!

As you can see in this link it's one of the most popular issues with many stars in google code but still no response from google! You can also add stars to this issue, maybe google hears that!

forward declaration of a struct in C?

A struct (without a typedef) often needs to (or should) be with the keyword struct when used.

struct A;                      // forward declaration
void function( struct A *a );  // using the 'incomplete' type only as pointer

If you typedef your struct you can leave out the struct keyword.

typedef struct A A;          // forward declaration *and* typedef
void function( A *a );

Note that it is legal to reuse the struct name

Try changing the forward declaration to this in your code:

typedef struct context context;

It might be more readable to do add a suffix to indicate struct name and type name:

typedef struct context_s context_t;

Creating new database from a backup of another Database on the same server?

Checking the Options Over Write Database worked for me :)

enter image description here

How to run Gradle from the command line on Mac bash

./gradlew

Your directory with gradlew is not included in the PATH, so you must specify path to the gradlew. . means "current directory".

How do I find numeric columns in Pandas?

You could use select_dtypes method of DataFrame. It includes two parameters include and exclude. So isNumeric would look like:

numerics = ['int16', 'int32', 'int64', 'float16', 'float32', 'float64']

newdf = df.select_dtypes(include=numerics)

Bootstrap change carousel height

For Bootstrap 4

In the same line as image add height: 300px;

<img src="..." style="height: 300px;" class="d-block w-100" alt="image">

Secure random token in Node.js

The up-to-date right way to do this asynchronously using ES 2016 standards of async and await (as of Node 7) would be the following:

const crypto = require('crypto');

function generateToken({ stringBase = 'base64', byteLength = 48 } = {}) {
  return new Promise((resolve, reject) => {
    crypto.randomBytes(byteLength, (err, buffer) => {
      if (err) {
        reject(err);
      } else {
        resolve(buffer.toString(stringBase));
      }
    });
  });
}

async function handler(req, res) {
   // default token length
   const newToken = await generateToken();
   console.log('newToken', newToken);

   // pass in parameters - adjust byte length
   const shortToken = await generateToken({byteLength: 20});
   console.log('newToken', shortToken);
}

This works out of the box in Node 7 without any Babel transformations

Maven dependency for Servlet 3.0 API?

This seems to be added recently:

https://repo1.maven.org/maven2/javax/servlet/javax.servlet-api/3.0.1/

<dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.0.1</version>
        <scope>provided</scope>
</dependency>

How do I convert a list of ascii values to a string in python?

Same basic solution as others, but I personally prefer to use map instead of the list comprehension:


>>> L = [104, 101, 108, 108, 111, 44, 32, 119, 111, 114, 108, 100]
>>> ''.join(map(chr,L))
'hello, world'

how to call a variable in code behind to aspx page

I would create a property to access the variable, like this:

protected string Test
{
    get; set;
}

And in your markup:

<%= this.Test %>

Extract MSI from EXE

The only way to do that is running the exe and collect the MSI. The thing you must take care of is that if you are tranforming the MSI using MST they might get lost.

I use this batch commandline:

SET TMP=c:\msipath

MD "%TMP%"

SET TEMP=%TMP%

start /d "c:\install" install.exe /L1033

PING 1.1.1.1 -n 1 -w 10000 >NUL

for /R "%TMP%" %%f in (*.msi) do copy "%%f" "%TMP%"

taskkill /F /IM msiexec.exe /T

What's the best/easiest GUI Library for Ruby?

Try visualruby you can easily build your forms using the glade interface designer, then write pure ruby code to animate them. Its much easier than the options mentioned above because you don't have to hand-code everything.

You can see example videos on the visualruby website.

cvc-elt.1: Cannot find the declaration of element 'MyElement'

Your schema is for its target namespace http://www.example.org/Test so it defines an element with name MyElement in that target namespace http://www.example.org/Test. Your instance document however has an element with name MyElement in no namespace. That is why the validating parser tells you it can't find a declaration for that element, you haven't provided a schema for elements in no namespace.

You either need to change the schema to not use a target namespace at all or you need to change the instance to use e.g. <MyElement xmlns="http://www.example.org/Test">A</MyElement>.

Jquery UI Datepicker not displaying

it's the css file in the new one doesn't work. Try to include the old 1.7.* css file on your header too, and try again.

Also, did you try to do a .datepicker( "show" ) right after it constructed?

creating Hashmap from a JSON String

consider this json string

{
    "12": [
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/12/12_960x540_200k.mp4/manifest.mpd",
            "video_bitrate": "200k",
            "audio_bitrate": "32k",
            "video_width": 960,
            "video_height": 540,
            "file_size": 125465600
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/12/12_960x540_80k.mp4/manifest.mpd",
            "video_bitrate": "80k",
            "audio_bitrate": "32k",
            "video_width": 960,
            "video_height": 540,
            "file_size": 50186240
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/12/12_640x360_201k.mp4/manifest.mpd",
            "video_bitrate": "201k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 145934731
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/12/12_640x360_199k.mp4/manifest.mpd",
            "video_bitrate": "199k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 145800030
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/12/12_640x360_79k.mp4/manifest.mpd",
            "video_bitrate": "79k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 71709477
        }
    ],
    "13": [
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/13/13_960x540_200k.mp4/manifest.mpd",
            "video_bitrate": "200k",
            "audio_bitrate": "32k",
            "video_width": 960,
            "video_height": 540,
            "file_size": 172902400
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/13/13_960x540_80k.mp4/manifest.mpd",
            "video_bitrate": "80k",
            "audio_bitrate": "32k",
            "video_width": 960,
            "video_height": 540,
            "file_size": 69160960
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/13/13_640x360_201k.mp4/manifest.mpd",
            "video_bitrate": "201k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 199932081
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/13/13_640x360_199k.mp4/manifest.mpd",
            "video_bitrate": "199k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 199630781
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/13/13_640x360_79k.mp4/manifest.mpd",
            "video_bitrate": "79k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 98303415
        }
    ],
    "14": [
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/14/14_960x540_200k.mp4/manifest.mpd",
            "video_bitrate": "200k",
            "audio_bitrate": "32k",
            "video_width": 960,
            "video_height": 540,
            "file_size": 205747200
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/14/14_960x540_80k.mp4/manifest.mpd",
            "video_bitrate": "80k",
            "audio_bitrate": "32k",
            "video_width": 960,
            "video_height": 540,
            "file_size": 82298880
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/14/14_640x360_201k.mp4/manifest.mpd",
            "video_bitrate": "201k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 237769546
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/14/14_640x360_199k.mp4/manifest.mpd",
            "video_bitrate": "199k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 237395552
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/14/14_640x360_79k.mp4/manifest.mpd",
            "video_bitrate": "79k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 116885686
        }
    ],
    "15": [
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/15/15_960x540_200k.mp4/manifest.mpd",
            "video_bitrate": "200k",
            "audio_bitrate": "32k",
            "video_width": 960,
            "video_height": 540,
            "file_size": 176128000
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/15/15_960x540_80k.mp4/manifest.mpd",
            "video_bitrate": "80k",
            "audio_bitrate": "32k",
            "video_width": 960,
            "video_height": 540,
            "file_size": 70451200
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/15/15_640x360_201k.mp4/manifest.mpd",
            "video_bitrate": "201k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 204263286
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/15/15_640x360_199k.mp4/manifest.mpd",
            "video_bitrate": "199k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 204144447
        },
        {
            "dash_url": "http://mediaserver.superprofs.com:1935/vods3/_definst_/mp4:amazons3/superprofs-media/private/lectures/15/15_640x360_79k.mp4/manifest.mpd",
            "video_bitrate": "79k",
            "audio_bitrate": "32k",
            "video_width": 640,
            "video_height": 360,
            "file_size": 100454382
        }
    ]
}

using jackson parser

 private static ObjectMapper underScoreToCamelCaseMapper;

    static {
        final DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

        underScoreToCamelCaseMapper = new ObjectMapper();
        underScoreToCamelCaseMapper.setDateFormat(df);
        underScoreToCamelCaseMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
        underScoreToCamelCaseMapper.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY);
        underScoreToCamelCaseMapper.setPropertyNamingStrategy(
                PropertyNamingStrategy.CAMEL_CASE_TO_LOWER_CASE_WITH_UNDERSCORES);
}
    public static <T> T parseUnderScoredResponse(String json, Class<T> classOfT) {
        try {
            if (json == null) {
                return null;
            }
            return underScoreToCamelCaseMapper.readValue(json, classOfT);

        } catch (JsonParseException e) {
        } catch (JsonMappingException e) {
        } catch (IOException e) {
        }
        return null;
    }

use following code to parse

 HashMap<String, ArrayList<Video>> integerArrayListHashMap =
                JsonHandler.parseUnderScoredResponse(test, MyHashMap.class);

where MyHashMap is

 private static class MyHashMap extends HashMap<String,ArrayList<Video>>{
    }

Warning: mysqli_query() expects parameter 1 to be mysqli, null given in

use global scope on your $con and put it inside your getPosts() function like so.

function getPosts() {
global $con;
$query = mysqli_query($con,"SELECT * FROM Blog");
while($row = mysqli_fetch_array($query))
    {
        echo "<div class=\"blogsnippet\">";
        echo "<h4>" . $row['Title'] . "</h4>" . $row['SubHeading'];
        echo "</div>";
    }
}

Java AES encryption and decryption

Try this, a simpler solution.

byte[] salt = "ThisIsASecretKey".getBytes();
Key key = new SecretKeySpec(salt, 0, 16, "AES");

Cipher cipher = Cipher.getInstance("AES");

ORA-01017 Invalid Username/Password when connecting to 11g database from 9i client

Oracle 11 G and 12 C versions suggest to use more complex passwords, Although there is no issues during the user creation. The password must be alphanumeric and with special character.

Verify the password version and status of the user:

select * from dba_users where username = <user_name>;

Amend it to be like below in case of 11G 12C:

alter user <user_name> identified by Pass2019$;

Now test connection!

The Web Application Project [...] is configured to use IIS. The Web server [...] could not be found.

If you are connected via TFS, open your project.csproj.user file and check for

<UseIISExpress>false</UseIISExpress>

and change it to true.

<UseIISExpress>true</UseIISExpress>

Linux/Unix command to determine if process is running?

You should know the PID of your process.

When you launch it, its PID will be recorded in the $! variable. Save this PID into a file.

Then you will need to check if this PID corresponds to a running process. Here's a complete skeleton script:

FILE="/tmp/myapp.pid"

if [ -f $FILE ];
then
   PID=$(cat $FILE)
else
   PID=1
fi

ps -o pid= -p $PID
if [ $? -eq 0 ]; then
  echo "Process already running."  
else
  echo "Starting process."
  run_my_app &
  echo $! > $FILE
fi

Based on the answer of peterh. The trick for knowing if a given PID is running is in the ps -o pid= -p $PID instruction.

What is the use of the JavaScript 'bind' method?

/**
 * Bind is a method inherited from Function.prototype same like call and apply
 * It basically helps to bind a function to an object's context during initialisation 
 * 
 * */

window.myname = "Jineesh";  
var foo = function(){ 
  return this.myname;
};

//IE < 8 has issues with this, supported in ecmascript 5
var obj = { 
    myname : "John", 
    fn:foo.bind(window)// binds to window object
}; 
console.log( obj.fn() ); // Returns Jineesh

Can you change what a symlink points to after it is created?

Wouldn't unlinking it and creating the new one do the same thing in the end anyway?

How do I read configuration settings from Symfony2 config.yml?

Rather than defining contact_email within app.config, define it in a parameters entry:

parameters:
    contact_email: [email protected]

You should find the call you are making within your controller now works.

Applying an ellipsis to multiline text

Please check this css for ellipsis to multi-line text

_x000D_
_x000D_
body {_x000D_
  margin: 0;_x000D_
  padding: 50px;_x000D_
}_x000D_
_x000D_
/* mixin for multiline */_x000D_
.block-with-text {_x000D_
  overflow: hidden;_x000D_
  position: relative;_x000D_
  line-height: 1.2em;_x000D_
  max-height: 6em;_x000D_
  text-align: justify;_x000D_
  margin-right: -1em;_x000D_
  padding-right: 1em;_x000D_
}_x000D_
.block-with-text:before {_x000D_
  content: '...';_x000D_
  position: absolute;_x000D_
  right: 0;_x000D_
  bottom: 0;_x000D_
}_x000D_
.block-with-text:after {_x000D_
  content: '';_x000D_
  position: absolute;_x000D_
  right: 0;_x000D_
  width: 1em;_x000D_
  height: 1em;_x000D_
  margin-top: 0.2em;_x000D_
  background: white;_x000D_
}
_x000D_
<p class="block-with-text">The Hitch Hiker's Guide to the Galaxy has a few things to say on the subject of towels. A towel, it says, is about the most massivelyuseful thing an interstellar hitch hiker can have. Partly it has great practical value - you can wrap it around you for warmth as you bound across the cold moons of  Jaglan Beta; you can lie on it on the brilliant marble-sanded beaches of Santraginus V, inhaling the heady sea vapours; you can sleep under it beneath the stars which shine so redly on the desert world of Kakrafoon;  use it to sail a mini raft down the slow heavy river Moth; wet it for use in hand-to-hand-combat; wrap it round your head to ward off noxious fumes or to avoid the gaze of the Ravenous Bugblatter Beast of Traal (a mindboggingly stupid animal, it assumes that if you can't see it, it can't see you - daft as a bush, but very ravenous); you can wave your towel in emergencies as a distress signal, and of course dry yourself off with it if it still seems to be clean enough. More importantly, a towel has immense psychological value. For some reason, if a strag (strag: non-hitch hiker) discovers that a hitch hiker has his towel with him, he will automatically assume that he is also in possession of a toothbrush, face flannel, soap, tin of biscuits, flask, compass, map, ball of string, gnat spray, wet weather gear, space suit etc., etc. Furthermore, the strag will then happily lend the hitch hiker any of these or a dozen other items that the hitch hiker might accidentally have "lost". What the strag will think is that any man who can hitch the length and breadth of the galaxy, rough it, slum it, struggle against terrible odds, win through, and still knows where his towel is is clearly a man to be reckoned with.</p>
_x000D_
_x000D_
_x000D_

Checking if type == list in python

You should try using isinstance()

if isinstance(object, list):
       ## DO what you want

In your case

if isinstance(tmpDict[key], list):
      ## DO SOMETHING

To elaborate:

x = [1,2,3]
if type(x) == list():
    print "This wont work"
if type(x) == list:                  ## one of the way to see if it's list
    print "this will work"           
if type(x) == type(list()):
    print "lets see if this works"
if isinstance(x, list):              ## most preferred way to check if it's list
    print "This should work just fine"

The difference between isinstance() and type() though both seems to do the same job is that isinstance() checks for subclasses in addition, while type() doesn’t.

How can I shrink the drawable on a button?

If you want to use 1 image and display it in different size, you can use scale drawable ( http://developer.android.com/guide/topics/resources/drawable-resource.html#Scale ).

Search for "does-not-contain" on a DataFrame in pandas

I had to get rid of the NULL values before using the command recommended by Andy above. An example:

df = pd.DataFrame(index = [0, 1, 2], columns=['first', 'second', 'third'])
df.ix[:, 'first'] = 'myword'
df.ix[0, 'second'] = 'myword'
df.ix[2, 'second'] = 'myword'
df.ix[1, 'third'] = 'myword'
df

    first   second  third
0   myword  myword   NaN
1   myword  NaN      myword 
2   myword  myword   NaN

Now running the command:

~df["second"].str.contains(word)

I get the following error:

TypeError: bad operand type for unary ~: 'float'

I got rid of the NULL values using dropna() or fillna() first and retried the command with no problem.

What is a vertical tab?

I believe it's still being used, not sure exactly. There might be even a key combination of it.

As English is written Left to Right, Arabic Right to Left, there are languages in world that are also written top to bottom. In that case a vertical tab might be useful same as the horizontal tab is used for English text.

I tried searching, but couldn't find anything useful yet.

string in namespace std does not name a type

You need to add:

#include <string>

In your header file.

How to handle invalid SSL certificates with Apache HttpClient?

Once you have a Java Cert Store (by using the great InstallCert class created above), you can get java to use it by passing the "javax.net.ssl.trustStore" param at java startup.

Ex:

java -Djavax.net.ssl.trustStore=/path/to/jssecacerts MyClassName

Return multiple values from a function in swift

//By : Dhaval Nimavat
    import UIKit

   func weather_diff(country1:String,temp1:Double,country2:String,temp2:Double)->(c1:String,c2:String,diff:Double)
   {
    let c1 = country1
    let c2 = country2
    let diff = temp1 - temp2
    return(c1,c2,diff)
   }

   let result = 
   weather_diff(country1: "India", temp1: 45.5, country2: "Canada", temp2:    18.5)
   print("Weather difference between \(result.c1) and \(result.c2) is \(result.diff)")

How to make ConstraintLayout work with percentage values?

For someone that might find useful, you can use layout_constraintDimensionRatio im any child view inside a ConstraintLayout and we can define the Height or Width a ratio of the other dimension( at least one must be 0dp either width or heigh) example

 <ImageView
        android:layout_width="wrap_content"
        android:layout_height="0dp"
        android:src="@drawable/top_image"
        app:layout_constraintDimensionRatio="16:9"        
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"/>

in this case the aspect ratio it's 16:9 app:layout_constraintDimensionRatio="16:9" you can find more info HERE

Multiple input in JOptionPane.showInputDialog

this is my solution

JTextField username = new JTextField();
JTextField password = new JPasswordField();
Object[] message = {
    "Username:", username,
    "Password:", password
};

int option = JOptionPane.showConfirmDialog(null, message, "Login", JOptionPane.OK_CANCEL_OPTION);
if (option == JOptionPane.OK_OPTION) {
    if (username.getText().equals("h") && password.getText().equals("h")) {
        System.out.println("Login successful");
    } else {
        System.out.println("login failed");
    }
} else {
    System.out.println("Login canceled");
}

Python read JSON file and modify

try this script:

with open("data.json") as f:
    data = json.load(f)
    data["id"] = 134
    json.dump(data, open("data.json", "w"), indent = 4)

the result is:

{
    "name":"mynamme",
    "id":134
}

Just the arrangement is different, You can solve the problem by converting the "data" type to a list, then arranging it as you wish, then returning it and saving the file, like that:

index_add = 0
with open("data.json") as f:
    data = json.load(f)
    data_li = [[k, v] for k, v in data.items()]
    data_li.insert(index_add, ["id", 134])
    data = {data_li[i][0]:data_li[i][1] for i in range(0, len(data_li))}
    json.dump(data, open("data.json", "w"), indent = 4)

the result is:

{
    "id":134,
    "name":"myname"
}

you can add if condition in order not to repeat the key, just change it, like that:

index_add = 0
n_k = "id"
n_v = 134
with open("data.json") as f:
    data = json.load(f)
    if n_k in data:
        data[n_k] = n_v
    else:
       data_li = [[k, v] for k, v in data.items()]
       data_li.insert(index_add, [n_k, n_v])
       data = {data_li[i][0]:data_li[i][1] for i in range(0, len(data_li))}
    json.dump(data, open("data.json", "w"), indent = 4)

Filezilla FTP Server Fails to Retrieve Directory Listing

File > Site Manager > Select your site > Transfer Settings > Active

Works for me.

Java double comparison epsilon

If you can use BigDecimal, then use it, else:

/**
  *@param precision number of decimal digits
  */
public static boolean areEqualDouble(double a, double b, int precision) {
   return Math.abs(a - b) <= Math.pow(10, -precision);
}

Mongodb find() query : return only unique values (no duplicates)

I think you can use db.collection.distinct(fields,query)

You will be able to get the distinct values in your case for NetworkID.

It should be something like this :

Db.collection.distinct('NetworkID')

How to pass a file path which is in assets folder to File(String path)?

Unless you unpack them, assets remain inside the apk. Accordingly, there isn't a path you can feed into a File. The path you've given in your question will work with/in a WebView, but I think that's a special case for WebView.

You'll need to unpack the file or use it directly.

If you have a Context, you can use context.getAssets().open("myfoldername/myfilename"); to open an InputStream on the file. With the InputStream you can use it directly, or write it out somewhere (after which you can use it with File).

Getting a 500 Internal Server Error on Laravel 5+ Ubuntu 14.04

Make sure a .env file, containing an APP_KEY, exists in root.

What should be in the .env hasn't been explicitly stated in other solutions, and thought I'd boil it down to the sentence above.

This fixed my 500 error on a fresh install of Laravel.

Steps:

  1. Create a .env file in root (e.g. touch .env)
  2. Make sure it contains at least one line: APP_KEY=
  3. Generate an app key in terminal: php artisan key:generate

Notes:

  • My particular installation didn't include any .env whatsoever (example or otherwise)

  • Simply having a blank .env does not work.

  • A .env containing parameters, but no APP_KEY parameter, does not work.

Bug?: When generating an app key in terminal, it may report as successful, however no key will actually get placed in the .env if the file has no pre-existing APP_KEY= line.

As a reference, here's the official .env with useful baseline parameters. Copy-paste what you need:

https://github.com/laravel/laravel/blob/master/.env.example

facet label font size

This should get you started:

R> qplot(hwy, cty, data = mpg) + 
       facet_grid(. ~ manufacturer) + 
       theme(strip.text.x = element_text(size = 8, colour = "orange", angle = 90))

See also this question: How can I manipulate the strip text of facet plots in ggplot2?

How can I print literal curly-brace characters in a string and also use .format on it?

If you need curly braces within a f-string template that can be formatted, you need to output a string containing two curly braces within a set of curly braces for the f-string:

css_template = f"{{tag}} {'{{'} margin: 0; padding: 0;{'}}'}"
for_p = css_template.format(tag="p")
# 'p { margin: 0; padding: 0;}'

How to Delete a topic in apache kafka

Deletion of a topic has been supported since 0.8.2.x version. You have to enable topic deletion (setting delete.topic.enable to true) on all brokers first.

Note: Ever since 1.0.x, the functionality being stable, delete.topic.enable is by default true.

Follow this step by step process for manual deletion of topics

  1. Stop Kafka server
  2. Delete the topic directory, on each broker (as defined in the logs.dirs and log.dir properties) with rm -rf command
  3. Connect to Zookeeper instance: zookeeper-shell.sh host:port
  4. From within the Zookeeper instance:
    1. List the topics using: ls /brokers/topics
    2. Remove the topic folder from ZooKeeper using: rmr /brokers/topics/yourtopic
    3. Exit the Zookeeper instance (Ctrl+C)
  5. Restart Kafka server
  6. Confirm if it was deleted or not by using this command kafka-topics.sh --list --zookeeper host:port

Unable to connect with remote debugger

  1. react-native start --reset-cache in one tab and react-native run-android in another
  2. adb reverse tcp:8081 tcp:8081 ( so you could add it to your scripts and just run yarn run adb-reverse)
  3. If you're using android, Instead of shake your phone a great tip is run adb commands.

So you can run:

  • adb shell input keyevent 82 (menu option )
  • adb shell input keyevent 46 46 ( reload )

PHP form send email to multiple recipients

If i understood correct try this one

$headers = "Bcc: [email protected]";

or

$headers = "Cc: [email protected]";

Validate email with a regex in jQuery

You probably want to use a regex like the one described here to check the format. When the form's submitted, run the following test on each field:

var userinput = $(this).val();
var pattern = /^\b[A-Z0-9._%-]+@[A-Z0-9.-]+\.[A-Z]{2,4}\b$/i

if(!pattern.test(userinput))
{
  alert('not a valid e-mail address');
}?

Can I load a .NET assembly at runtime and instantiate a type knowing only the name?

I found this question and some answers very useful, however I did have path problems, so this answer would cover loading library by finding bin directory path.

First solution:

string assemblyName = "library.dll";
string assemblyPath = HttpContext.Current.Server.MapPath("~/bin/" + assemblyName);
Assembly assembly = Assembly.LoadFrom(assemblyPath);
Type T = assembly.GetType("Company.Project.Classname");
Company.Project.Classname instance = (Company.Project.Classname) Activator.CreateInstance(T);

Second solution

string assemblyName = "library.dll";
string assemblyPath = HttpContext.Current.Server.MapPath("~/bin/" + assemblyName);
Assembly assembly = Assembly.LoadFile(assemblyPath);
(Company.Project.Classname) instance = (Company.Project.Classname) assembly.CreateInstance("Company.Project.Classname");

You can use same principle for interfaces (you would be creating a class but casting to interface), such as:

(Company.Project.Interfacename) instance = (Company.Project.Interfacename) assembly.CreateInstance("Company.Project.Classname");

This example is for web application but similar could be used for Desktop application, only path is resolved in different way, for example

Path.GetDirectoryName(Application.ExecutablePath)

PyTorch: How to get the shape of a Tensor as a list of int

For PyTorch v1.0 and possibly above:

>>> import torch
>>> var = torch.tensor([[1,0], [0,1]])

# Using .size function, returns a torch.Size object.
>>> var.size()
torch.Size([2, 2])
>>> type(var.size())
<class 'torch.Size'>

# Similarly, using .shape
>>> var.shape
torch.Size([2, 2])
>>> type(var.shape)
<class 'torch.Size'>

You can cast any torch.Size object to a native Python list:

>>> list(var.size())
[2, 2]
>>> type(list(var.size()))
<class 'list'>

In PyTorch v0.3 and 0.4:

Simply list(var.size()), e.g.:

>>> import torch
>>> from torch.autograd import Variable
>>> from torch import IntTensor
>>> var = Variable(IntTensor([[1,0],[0,1]]))

>>> var
Variable containing:
 1  0
 0  1
[torch.IntTensor of size 2x2]

>>> var.size()
torch.Size([2, 2])

>>> list(var.size())
[2, 2]

How to drop columns by name in a data frame

Here's a quick solution for this. Say, you have a data frame X with three columns A, B and C:

> X<-data.frame(A=c(1,2),B=c(3,4),C=c(5,6))
> X
  A B C
1 1 3 5
2 2 4 6

If I want to remove a column, say B, just use grep on colnames to get the column index, which you can then use to omit the column.

> X<-X[,-grep("B",colnames(X))]

Your new X data frame would look like the following (this time without the B column):

> X
  A C
1 1 5
2 2 6

The beauty of grep is that you can specify multiple columns that match the regular expression. If I had X with five columns (A,B,C,D,E):

> X<-data.frame(A=c(1,2),B=c(3,4),C=c(5,6),D=c(7,8),E=c(9,10))
> X
  A B C D  E
1 1 3 5 7  9
2 2 4 6 8 10

Take out columns B and D:

> X<-X[,-grep("B|D",colnames(X))]
> X
  A C  E
1 1 5  9
2 2 6 10

EDIT: Considering the grepl suggestion of Matthew Lundberg in the comments below:

> X<-data.frame(A=c(1,2),B=c(3,4),C=c(5,6),D=c(7,8),E=c(9,10))
> X
  A B C D  E
1 1 3 5 7  9
2 2 4 6 8 10
> X<-X[,!grepl("B|D",colnames(X))]
> X
  A C  E
1 1 5  9
2 2 6 10

If I try to drop a column that's non-existent,nothing should happen:

> X<-X[,!grepl("G",colnames(X))]
> X
  A C  E
1 1 5  9
2 2 6 10

Can I specify maxlength in css?

No. This needs to be done in the HTML. You could set the value with Javascript if you need to though.

Sending and receiving data over a network using TcpClient

I have had luck using the socket object directly (rather than the TCP client). I create a Server object that looks something like this (I've edited some stuff such as exception handling out for brevity, but I hope that the idea comes across.)...

public class Server()
{
    private Socket sock;
    // You'll probably want to initialize the port and address in the
    // constructor, or via accessors, but to start your server listening
    // on port 8080 and on any IP address available on the machine...
    private int port = 8080;
    private IPAddress addr = IPAddress.Any;

    // This is the method that starts the server listening.
    public void Start()
    {
        // Create the new socket on which we'll be listening.
        this.sock = new Socket(
            addr.AddressFamily,
            SocketType.Stream,
            ProtocolType.Tcp);
        // Bind the socket to the address and port.
        sock.Bind(new IPEndPoint(this.addr, this.port));
        // Start listening.
        this.sock.Listen(this.backlog);
        // Set up the callback to be notified when somebody requests
        // a new connection.
        this.sock.BeginAccept(this.OnConnectRequest, sock);
    }

    // This is the method that is called when the socket recives a request
    // for a new connection.
    private void OnConnectRequest(IAsyncResult result)
    {
        // Get the socket (which should be this listener's socket) from
        // the argument.
        Socket sock = (Socket)result.AsyncState;
        // Create a new client connection, using the primary socket to
        // spawn a new socket.
        Connection newConn = new Connection(sock.EndAccept(result));
        // Tell the listener socket to start listening again.
        sock.BeginAccept(this.OnConnectRequest, sock);
    }
}

Then, I use a separate Connection class to manage the individual connection with the remote host. That looks something like this...

public class Connection()
{
    private Socket sock;
    // Pick whatever encoding works best for you.  Just make sure the remote 
    // host is using the same encoding.
    private Encoding encoding = Encoding.UTF8;

    public Connection(Socket s)
    {
        this.sock = s;
        // Start listening for incoming data.  (If you want a multi-
        // threaded service, you can start this method up in a separate
        // thread.)
        this.BeginReceive();
    }

    // Call this method to set this connection's socket up to receive data.
    private void BeginReceive()
    {
        this.sock.BeginReceive(
                this.dataRcvBuf, 0,
                this.dataRcvBuf.Length,
                SocketFlags.None,
                new AsyncCallback(this.OnBytesReceived),
                this);
    }

    // This is the method that is called whenever the socket receives
    // incoming bytes.
    protected void OnBytesReceived(IAsyncResult result)
    {
        // End the data receiving that the socket has done and get
        // the number of bytes read.
        int nBytesRec = this.sock.EndReceive(result);
        // If no bytes were received, the connection is closed (at
        // least as far as we're concerned).
        if (nBytesRec <= 0)
        {
            this.sock.Close();
            return;
        }
        // Convert the data we have to a string.
        string strReceived = this.encoding.GetString(
            this.dataRcvBuf, 0, nBytesRec);

        // ...Now, do whatever works best with the string data.
        // You could, for example, look at each character in the string
        // one-at-a-time and check for characters like the "end of text"
        // character ('\u0003') from a client indicating that they've finished
        // sending the current message.  It's totally up to you how you want
        // the protocol to work.

        // Whenever you decide the connection should be closed, call 
        // sock.Close() and don't call sock.BeginReceive() again.  But as long 
        // as you want to keep processing incoming data...

        // Set up again to get the next chunk of data.
        this.sock.BeginReceive(
            this.dataRcvBuf, 0,
            this.dataRcvBuf.Length,
            SocketFlags.None,
            new AsyncCallback(this.OnBytesReceived),
            this);

    }
}

You can use your Connection object to send data by calling its Socket directly, like so...

this.sock.Send(this.encoding.GetBytes("Hello to you, remote host."));

As I said, I've tried to edit the code here for posting, so I apologize if there are any errors in it.

How to add element into ArrayList in HashMap

Typical code is to create an explicit method to add to the list, and create the ArrayList on the fly when adding. Note the synchronization so the list only gets created once!

@Override
public synchronized boolean addToList(String key, Item item) {
   Collection<Item> list = theMap.get(key);
   if (list == null)  {
      list = new ArrayList<Item>();  // or, if you prefer, some other List, a Set, etc...
      theMap.put(key, list );
   }

   return list.add(item);
}

unsigned APK can not be installed

You cannot install an unsigned application on a phone. You can only use it to test with an emulator. If you still want to go ahead, you can try self-signing the application.

Also, since you are installing the application from an SD card, I hope you have the necessary permissions set. Do go through stackoverflow.com and look at questions regarding installation of applications from an SD card - there have been many and they have been asked before.

Hope that helps.

Python convert decimal to hex

I recently made this python program to convert Decimal to Hexadecimal, please check this out. This is my first Answer in stack overflow .

decimal = int(input("Enter the Decimal no that you want to convert to Hexadecimal : "))
intact = decimal
hexadecimal = ''
dictionary = {1:'1',2:'2',3:'3',4:'4',5:'5',6:'6',7:'7',8:'8',9:'9',10:'A',11:'B',12:'C',13:'D',14:'E',15:'F'}

while(decimal!=0):
    c = decimal%16 
    hexadecimal =  dictionary[c] + hexadecimal 
    decimal = int(decimal/16)

print(f"{intact} is {hexadecimal} in Hexadecimal")

When you Execute this code this will give output as:

Enter the Decimal no that you want to convert to Hexadecimal : 2766

2766 is ACE in Hexadecimal

Azure SQL Database "DTU percentage" metric

From this document, this DTU percent is determined by this query:

SELECT end_time,   
  (SELECT Max(v)    
   FROM (VALUES (avg_cpu_percent), (avg_data_io_percent), 
(avg_log_write_percent)) AS    
   value(v)) AS [avg_DTU_percent]   
FROM sys.dm_db_resource_stats;  

looks like the max of avg_cpu_percent, avg_data_io_percent and avg_log_write_percent

Reference:

https://docs.microsoft.com/en-us/sql/relational-databases/system-dynamic-management-views/sys-dm-db-resource-stats-azure-sql-database

How do I get out of 'screen' without typing 'exit'?

  • Ctrl + A, Ctrl + \ - Exit screen and terminate all programs in this screen. It is helpful, for example, if you need to close a tty connection.

  • Ctrl + D, D or - Ctrl + A, Ctrl + D - "minimize" screen and screen -r to restore it.

Why does my 'git branch' have no master?

I actually had the same problem with a completely new repository. I had even tried creating one with git checkout -b master, but it would not create the branch. I then realized if I made some changes and committed them, git created my master branch.

String.strip() in Python

In this case, you might get some differences. Consider a line like:

"foo\tbar "

In this case, if you strip, then you'll get {"foo":"bar"} as the dictionary entry. If you don't strip, you'll get {"foo":"bar "} (note the extra space at the end)

Note that if you use line.split() instead of line.split('\t'), you'll split on every whitespace character and the "striping" will be done during splitting automatically. In other words:

line.strip().split()

is always identical to:

line.split()

but:

line.strip().split(delimiter)

Is not necessarily equivalent to:

line.split(delimiter)

AngularJS does not send hidden field value

I had facing the same problem, I really need to send a key from my jsp to java script, It spend around 4h or more of my day to solve it.

I include this tag on my JavaScript/JSP:

_x000D_
_x000D_
 $scope.sucessMessage = function (){  _x000D_
     var message =     ($scope.messages.sucess).format($scope.portfolio.name,$scope.portfolio.id);_x000D_
     $scope.inforMessage = message;_x000D_
     alert(message);  _x000D_
}_x000D_
 _x000D_
_x000D_
String.prototype.format = function() {_x000D_
    var formatted = this;_x000D_
    for( var arg in arguments ) {_x000D_
        formatted = formatted.replace("{" + arg + "}", arguments[arg]);_x000D_
    }_x000D_
    return formatted;_x000D_
};
_x000D_
<!-- Messages definition -->_x000D_
<input type="hidden"  name="sucess"   ng-init="messages.sucess='<fmt:message  key='portfolio.create.sucessMessage' />'" >_x000D_
_x000D_
<!-- Message showed affter insert -->_x000D_
<div class="alert alert-info" ng-show="(inforMessage.length > 0)">_x000D_
    {{inforMessage}}_x000D_
</div>_x000D_
_x000D_
<!-- properties_x000D_
  portfolio.create.sucessMessage=Portf\u00f3lio {0} criado com sucesso! ID={1}. -->
_x000D_
_x000D_
_x000D_

The result was: Portfólio 1 criado com sucesso! ID=3.

Best Regards

How do I inject a controller into another controller in AngularJS

you can also use $rootScope to call a function/method of 1st controller from second controller like this,

.controller('ctrl1', function($rootScope, $scope) {
     $rootScope.methodOf2ndCtrl();
     //Your code here. 
})

.controller('ctrl2', function($rootScope, $scope) {
     $rootScope.methodOf2ndCtrl = function() {
     //Your code here. 
}
})

Alternative to Intersect in MySQL

For completeness here is another method for emulating INTERSECT. Note that the IN (SELECT ...) form suggested in other answers is generally more efficient.

Generally for a table called mytable with a primary key called id:

SELECT id
FROM mytable AS a
INNER JOIN mytable AS b ON a.id = b.id
WHERE
(a.col1 = "someval")
AND
(b.col1 = "someotherval")

(Note that if you use SELECT * with this query you will get twice as many columns as are defined in mytable, this is because INNER JOIN generates a Cartesian product)

The INNER JOIN here generates every permutation of row-pairs from your table. That means every combination of rows is generated, in every possible order. The WHERE clause then filters the a side of the pair, then the b side. The result is that only rows which satisfy both conditions are returned, just like intersection two queries would do.

How to make a simple rounded button in Storyboard?

The extension is the best option for this problem. Create an extension of View or Button

public extension UIView {
  //Round the corners
  func roundCorners(){
    let radius = bounds.maxX / 16
    layer.cornerRadius = radius
  }
}

Call it from the code

button.roundCorners()

Background images: how to fill whole div if image is small and vice versa

This will work like a charm.

background-image:url("http://assets.toptal.io/uploads/blog/category/logo/4/php.png");
background-repeat: no-repeat;
background-size: contain;

Python - Dimension of Data Frame

df.shape, where df is your DataFrame.

PHP Unset Session Variable

You can unset session variable using:

  1. session_unset - Frees all session variables (It is equal to using: $_SESSION = array(); for older deprecated code)
  2. unset($_SESSION['Products']); - Unset only Products index in session variable. (Remember: You have to use like a function, not as you used)
  3. session_destroy — Destroys all data registered to a session

To know the difference between using session_unset and session_destroy, read this SO answer. That helps.

python for increment inner loop

It seems that you want to use step parameter of range function. From documentation:

range(start, stop[, step]) This is a versatile function to create lists containing arithmetic progressions. It is most often used in for loops. The arguments must be plain integers. If the step argument is omitted, it defaults to 1. If the start argument is omitted, it defaults to 0. The full form returns a list of plain integers [start, start + step, start + 2 * step, ...]. If step is positive, the last element is the largest start + i * step less than stop; if step is negative, the last element is the smallest start + i * step greater than stop. step must not be zero (or else ValueError is raised). Example:

 >>> range(10) [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
 >>> range(1, 11) [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
 >>> range(0, 30, 5) [0, 5, 10, 15, 20, 25]
 >>> range(0, 10, 3) [0, 3, 6, 9]
 >>> range(0, -10, -1) [0, -1, -2, -3, -4, -5, -6, -7, -8, -9]
 >>> range(0) []
 >>> range(1, 0) []

In your case to get [0,2,4] you can use:

range(0,6,2)

OR in your case when is a var:

idx = None
for i in range(len(str1)):
    if idx and i < idx:
        continue
    for j in range(len(str2)):
        if str1[i+j] != str2[j]:
            break
    else:
        idx = i+j

List names of all tables in a SQL Server 2012 schema

select * from [schema_name].sys.tables

This should work. Make sure you are on the server which consists of your "[schema_name]"

java.net.UnknownHostException: Unable to resolve host "<url>": No address associated with hostname and End of input at character 0 of

I had the same exception in the simulator (Android Studio on OSX) but connecting to the same URL on the iOS simulator worked fine... Looks like it all stemmed from the fact I'd be running the simulator whilst connected to a personal hotspot for my internet connection and then came back later while connected to wifi and the simulator didn't like the new internet connection for some reason, seems like it thought the old hotspot was the current connection, which was no longer working..

Closing and relaunching the simulator worked!

Uncaught TypeError: Cannot set property 'value' of null

The problem is that you haven't got any element with the id u so that you are calling something that doesn't exist.
To fix that you have to add an id to the element.

<input id="u" type="text" class="searchbox1" name="search" placeholder="Search for Brand, Store or an Item..." value="text" />


And I've seen too you have added a value for the input, so it means the input is not empty and it will contain text. As result placeholder won't be displayed.

Finally there is a warning that W3Validator will say because of the "/" in the end. :

For the current document, the validator interprets strings like according to legacy rules that break the expectations of most authors and thus cause confusing warnings and error messages from the validator. This interpretation is triggered by HTML 4 documents or other SGML-based HTML documents. To avoid the messages, simply remove the "/" character in such contexts. NB: If you expect <FOO /> to be interpreted as an XML-compatible "self-closing" tag, then you need to use XHTML or HTML5.

In conclusion it says you have to remove the slash. Simply write this:

<input id="u" type="text" class="searchbox1" name="search" placeholder="Search for Brand, Store or an Item...">

Available text color classes in Bootstrap

The bootstrap 3 documentation lists this under helper classes: Muted, Primary, Success, Info, Warning, Danger.

The bootstrap 4 documentation lists this under utilities -> color, and has more options: primary, secondary, success, danger, warning, info, light, dark, muted, white.

To access them one uses the class text-[class-name]

So, if I want the primary text color for example I would do something like this:

<p class="text-primary">This text is the primary color.</p>

This is not a huge number of choices, but it's some.

How to use timeit module

# ????????? ????? ?????

def gen_prime(x):
    multiples = []
    results = []
    for i in range(2, x+1):
        if i not in multiples:
            results.append(i)
            for j in range(i*i, x+1, i):
                multiples.append(j)

    return results


import timeit

# ???????? ?????

start_time = timeit.default_timer()
gen_prime(3000)
print(timeit.default_timer() - start_time)

# start_time = timeit.default_timer()
# gen_prime(1001)
# print(timeit.default_timer() - start_time)

Event for Handling the Focus of the EditText

Here is the focus listener example.

editText.setOnFocusChangeListener(new OnFocusChangeListener() {
    @Override
    public void onFocusChange(View view, boolean hasFocus) {
        if (hasFocus) {
            Toast.makeText(getApplicationContext(), "Got the focus", Toast.LENGTH_LONG).show();
        } else {
            Toast.makeText(getApplicationContext(), "Lost the focus", Toast.LENGTH_LONG).show();
        }
    }
});

How to post query parameters with Axios?

axios signature for post is axios.post(url[, data[, config]]). So you want to send params object within the third argument:

.post(`/mails/users/sendVerificationMail`, null, { params: {
  mail,
  firstname
}})
.then(response => response.status)
.catch(err => console.warn(err));

This will POST an empty body with the two query params:

POST http://localhost:8000/api/mails/users/sendVerificationMail?mail=lol%40lol.com&firstname=myFirstName

Possible to iterate backwards through a foreach?

Elaborateling slighty on the nice answer by Jon Skeet, this could be versatile:

public static IEnumerable<T> Directional<T>(this IList<T> items, bool Forwards) {
    if (Forwards) foreach (T item in items) yield return item;
    else for (int i = items.Count-1; 0<=i; i--) yield return items[i];
}

And then use as

foreach (var item in myList.Directional(forwardsCondition)) {
    .
    .
}