Programs & Examples On #Jsr 275

JSR 275: Units Specification

Javascript loading CSV file into an array

You can't use AJAX to fetch files from the user machine. This is absolutely the wrong way to go about it.

Use the FileReader API:

<input type="file" id="file input">

js:

console.log(document.getElementById("file input").files); // list of File objects

var file = document.getElementById("file input").files[0];
var reader = new FileReader();
content = reader.readAsText(file);
console.log(content);

Then parse content as CSV. Keep in mind that your parser currently does not deal with escaped values in CSV like: value1,value2,"value 3","value ""4"""

Random color generator

Use getRandomColor() in place of "#0000FF":

_x000D_
_x000D_
function getRandomColor() {_x000D_
  var letters = '0123456789ABCDEF';_x000D_
  var color = '#';_x000D_
  for (var i = 0; i < 6; i++) {_x000D_
    color += letters[Math.floor(Math.random() * 16)];_x000D_
  }_x000D_
  return color;_x000D_
}_x000D_
_x000D_
_x000D_
_x000D_
function setRandomColor() {_x000D_
  $("#colorpad").css("background-color", getRandomColor());_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<div id="colorpad" style="width:300px;height:300px;background-color:#000">_x000D_
_x000D_
</div>_x000D_
<button onclick="setRandomColor()">Random Color</button>
_x000D_
_x000D_
_x000D_

CSS vertical-align: text-bottom;

Sometimes you can play with padding and margin top, add line-height, etc.

See fiddle.

Style and text forked from @aspirinemaga

.parent
{
    width:300px;
    line-height:30px;
    border:1px solid red;
    padding-top:20px;
}

LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method cannot be translated into a store expression

I got the same error in this case:

var result = Db.SystemLog
.Where(log =>
    eventTypeValues.Contains(log.EventType)
    && (
        search.Contains(log.Id.ToString())
        || log.Message.Contains(search)
        || log.PayLoad.Contains(search)
        || log.Timestamp.ToString(CultureInfo.CurrentUICulture).Contains(search)
    )
)
.OrderByDescending(log => log.Id)
.Select(r => r);

After spending way too much time debugging, I figured out that error appeared in the logic expression.

The first line search.Contains(log.Id.ToString()) does work fine, but the last line that deals with a DateTime object made it fail miserably:

|| log.Timestamp.ToString(CultureInfo.CurrentUICulture).Contains(search)

Remove the problematic line and problem solved.

I do not fully understand why, but it seems as ToString() is a LINQ expression for strings, but not for Entities. LINQ for Entities deals with database queries like SQL, and SQL has no notion of ToString(). As such, we can not throw ToString() into a .Where() clause.

But how then does the first line work? Instead of ToString(), SQL have CAST and CONVERT, so my best guess so far is that linq for entities uses that in some simple cases. DateTime objects are not always found to be so simple...

Java - sending HTTP parameters via POST method easily

Try this pattern:

public static PricesResponse getResponse(EventRequestRaw request) {

    // String urlParameters  = "param1=a&param2=b&param3=c";
    String urlParameters = Piping.serialize(request);

    HttpURLConnection conn = RestClient.getPOSTConnection(endPoint, urlParameters);

    PricesResponse response = null;

    try {
        // POST
        OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());
        writer.write(urlParameters);
        writer.flush();

        // RESPONSE
        BufferedReader reader = new BufferedReader(new InputStreamReader((conn.getInputStream()), StandardCharsets.UTF_8));
        String json = Buffering.getString(reader);
        response = (PricesResponse) Piping.deserialize(json, PricesResponse.class);

        writer.close();
        reader.close();

    } catch (Exception e) {
        e.printStackTrace();
    }

    conn.disconnect();

    System.out.println("PricesClient: " + response.toString());

    return response;
}

public static HttpURLConnection getPOSTConnection(String endPoint, String urlParameters) {

    return RestClient.getConnection(endPoint, "POST", urlParameters);

}


public static HttpURLConnection getConnection(String endPoint, String method, String urlParameters) {

    System.out.println("ENDPOINT " + endPoint + " METHOD " + method);
    HttpURLConnection conn = null;

    try {
        URL url = new URL(endPoint);
        conn = (HttpURLConnection) url.openConnection();
        conn.setRequestMethod(method);
        conn.setDoOutput(true);
        conn.setRequestProperty("Content-Type", "text/plain");

    } catch (IOException e) {
        e.printStackTrace();
    }

    return conn;
}

How to copy data from another workbook (excel)?

I was in need of copying the data from one workbook to another using VBA. The requirement was as mentioned below 1. On pressing an Active X button open the dialogue to select the file from which the data needs to be copied. 2. On clicking OK the value should get copied from a cell / range to currently working workbook.

I did not want to use the open function because it opens the workbook which will be annoying

Below is the code that I wrote in the VBA. Any improvement or new alternative is welcome.

Code: Here I am copying the A1:C4 content from a workbook to the A1:C4 of current workbook

    Private Sub CommandButton1_Click()
        Dim BackUp As String
        Dim cellCollection As New Collection
        Dim strSourceSheetName As String
        Dim strDestinationSheetName As String
        strSourceSheetName = "Sheet1" 'Mention the Source Sheet Name of Source Workbook
        strDestinationSheetName = "Sheet2" 'Mention the Destination Sheet Name of Destination Workbook


        Set cellCollection = GetCellsFromRange("A1:C4") 'Mention the Range you want to copy data from Source Workbook

        With Application.FileDialog(msoFileDialogOpen)
            .AllowMultiSelect = False
            .Show
            '.Filters.Add "Macro Enabled Xl", "*.xlsm;", 1

            For intWorkBookCount = 1 To .SelectedItems.Count
                Dim strWorkBookName As String
                strWorkBookName = .SelectedItems(intWorkBookCount)
                For cellCount = 1 To cellCollection.Count
                    On Error GoTo ErrorHandler
                    BackUp = Sheets(strDestinationSheetName).Range(cellCollection.Item(cellCount))
                    Sheets(strDestinationSheetName).Range(cellCollection.Item(cellCount)) = GetData(strWorkBookName, strSourceSheetName, cellCollection.Item(cellCount))
                    Dim strTempValue As String
                    strTempValue = Sheets(strDestinationSheetName).Range(cellCollection.Item(cellCount)).Value
                    If (strTempValue = "0") Then
                        strTempValue = BackUp
                    End If
Sheets(strDestinationSheetName).Range(cellCollection.Item(cellCount)) = strTempValue 
ErrorHandler:
                    If (Err.Number <> 0) Then
                            Sheets(strDestinationSheetName).Range(cellCollection.Item(cellCount)) = BackUp
                        Exit For
                    End If
                Next cellCount
            Next intWorkBookCount
        End With

    End Sub

    Function GetCellsFromRange(RangeInScope As String) As Collection
        Dim startCell As String
        Dim endCell As String
        Dim intStartColumn As Integer
        Dim intEndColumn As Integer
        Dim intStartRow As Integer
        Dim intEndRow As Integer
        Dim coll As New Collection

        startCell = Left(RangeInScope, InStr(RangeInScope, ":") - 1)
        endCell = Right(RangeInScope, Len(RangeInScope) - InStr(RangeInScope, ":"))
        intStartColumn = Range(startCell).Column
        intEndColumn = Range(endCell).Column
        intStartRow = Range(startCell).Row
        intEndRow = Range(endCell).Row

        For lngColumnCount = intStartColumn To intEndColumn
            For lngRowCount = intStartRow To intEndRow
                coll.Add (Cells(lngRowCount, lngColumnCount).Address(RowAbsolute:=False, ColumnAbsolute:=False))
            Next lngRowCount
        Next lngColumnCount

        Set GetCellsFromRange = coll
    End Function

    Function GetData(FileFullPath As String, SheetName As String, CellInScope As String) As String
        Dim Path As String
        Dim FileName As String
        Dim strFinalValue As String
        Dim doesSheetExist As Boolean

        Path = FileFullPath
        Path = StrReverse(Path)
        FileName = StrReverse(Left(Path, InStr(Path, "\") - 1))
        Path = StrReverse(Right(Path, Len(Path) - InStr(Path, "\") + 1))

        strFinalValue = "='" & Path & "[" & FileName & "]" & SheetName & "'!" & CellInScope
        GetData = strFinalValue
    End Function

Changing website favicon dynamically

Why not?

var link = document.querySelector("link[rel~='icon']");
if (!link) {
    link = document.createElement('link');
    link.rel = 'icon';
    document.getElementsByTagName('head')[0].appendChild(link);
}
link.href = 'https://stackoverflow.com/favicon.ico';

HTML checkbox - allow to check only one checkbox

The unique name identifier applies to radio buttons:

<input type="radio" />

change your checkboxes to radio and everything should be working

Execute external program

borrowed this shamely from here

Process process = new ProcessBuilder("C:\\PathToExe\\MyExe.exe","param1","param2").start();
InputStream is = process.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;

System.out.printf("Output of running %s is:", Arrays.toString(args));

while ((line = br.readLine()) != null) {
  System.out.println(line);
}

More information here

Other issues on how to pass commands here and here

How do I assign a port mapping to an existing Docker container?

For Windows & Mac Users, there is another pretty easy and friendly way to change the mapping port:

  1. download kitematic

  2. go to the settings page of the container, on the ports tab, you can directly modify the published port there.

  3. start the container again

Is there any difference between a GUID and a UUID?

GUID has longstanding usage in areas where it isn't necessarily a 128-bit value in the same way as a UUID. For example, the RSS specification defines GUIDs to be any string of your choosing, as long as it's unique, with an "isPermalink" attribute to specify that the value you're using is just a permalink back to the item being syndicated.

FB OpenGraph og:image not pulling images (possibly https?)

In addition, this problem also occurs when you add a user generated story (where you do not use og:image). For example:

POST /me/cookbook:eat?
  recipe=http://www.example.com/recipes/pizza/&
  image[0][url]=http://www.example.com/recipes/pizza/pizza.jpg&
  image[0][user_generated]=true&
  access_token=VALID_ACCESS_TOKEN

The above will only work with http and not with https. If you use https, you will get an error that says: Attached image () failed to upload

How to correctly close a feature branch in Mercurial?

One way is to just leave merged feature branches open (and inactive):

$ hg up default
$ hg merge feature-x
$ hg ci -m merge

$ hg heads
    (1 head)

$ hg branches
default    43:...
feature-x  41:...
    (2 branches)

$ hg branches -a
default    43:...
    (1 branch)

Another way is to close a feature branch before merging using an extra commit:

$ hg up feature-x
$ hg ci -m 'Closed branch feature-x' --close-branch
$ hg up default
$ hg merge feature-x
$ hg ci -m merge

$ hg heads
    (1 head)

$ hg branches
default    43:...
    (1 branch)

The first one is simpler, but it leaves an open branch. The second one leaves no open heads/branches, but it requires one more auxiliary commit. One may combine the last actual commit to the feature branch with this extra commit using --close-branch, but one should know in advance which commit will be the last one.

Update: Since Mercurial 1.5 you can close the branch at any time so it will not appear in both hg branches and hg heads anymore. The only thing that could possibly annoy you is that technically the revision graph will still have one more revision without childen.

Update 2: Since Mercurial 1.8 bookmarks have become a core feature of Mercurial. Bookmarks are more convenient for branching than named branches. See also this question:

How can I import a database with MySQL from terminal?

mysql -u username -ppassword dbname < /path/file-name.sql

example

mysql -u root -proot product < /home/myPC/Downloads/tbl_product.sql

Use this from terminal

Can I delete data from the iOS DeviceSupport directory?

More Suggestive answer supporting rmaddy's answer as our primary purpose is to delete unnecessary file and folder:

  1. Delete this folder after every few days interval. Most of the time, it occupy huge space!

      ~/Library/Developer/Xcode/DerivedData
    
  2. All your targets are kept in the archived form in Archives folder. Before you decide to delete contents of this folder, here is a warning - if you want to be able to debug deployed versions of your App, you shouldn’t delete the archives. Xcode will manage of archives and creates new file when new build is archived.

      ~/Library/Developer/Xcode/Archives
    
  3. iOS Device Support folder creates a subfolder with the device version as an identifier when you attach the device. Most of the time it’s just old stuff. Keep the latest version and rest of them can be deleted (if you don’t have an app that runs on 5.1.1, there’s no reason to keep the 5.1.1 directory/directories). If you really don't need these, delete. But we should keep a few although we test app from device mostly.

    ~/Library/Developer/Xcode/iOS DeviceSupport
    
  4. Core Simulator folder is familiar for many Xcode users. It’s simulator’s territory; that's where it stores app data. It’s obvious that you can toss the older version simulator folder/folders if you no longer support your apps for those versions. As it is user data, no big issue if you delete it completely but it’s safer to use ‘Reset Content and Settings’ option from the menu to delete all of your app data in a Simulator.

      ~/Library/Developer/CoreSimulator 
    

(Here's a handy shell command for step 5: xcrun simctl delete unavailable )

  1. Caches are always safe to delete since they will be recreated as necessary. This isn’t a directory; it’s a file of kind Xcode Project. Delete away!

    ~/Library/Caches/com.apple.dt.Xcode
    
  2. Additionally, Apple iOS device automatically syncs specific files and settings to your Mac every time they are connected to your Mac machine. To be on safe side, it’s wise to use Devices pane of iTunes preferences to delete older backups; you should be retaining your most recent back-ups off course.

     ~/Library/Application Support/MobileSync/Backup
    

Source: https://ajithrnayak.com/post/95441624221/xcode-users-can-free-up-space-on-your-mac

I got back about 40GB!

Looping through dictionary object

public class TestModels
{
    public Dictionary<int, dynamic> sp = new Dictionary<int, dynamic>();

    public TestModels()
    {
        sp.Add(0, new {name="Test One", age=5});
        sp.Add(1, new {name="Test Two", age=7});
    }
}

MaxLength Attribute not generating client-side validation attributes

In MVC 4 If you want maxlenght in input type text ? You can !

@Html.TextBoxFor(model => model.Item3.ADR_ZIP, new { @class = "gui-input ui-oblig", @maxlength = "5" })

SQLAlchemy: how to filter date field?

from app import SQLAlchemyDB as db

Chance.query.filter(Chance.repo_id==repo_id, 
                    Chance.status=="1", 
                    db.func.date(Chance.apply_time)<=end, 
                    db.func.date(Chance.apply_time)>=start).count()

it is equal to:

select
   count(id)
from
   Chance
where
   repo_id=:repo_id 
   and status='1'
   and date(apple_time) <= end
   and date(apple_time) >= start

wish can help you.

C# version of java's synchronized keyword?

You can use the lock statement instead. I think this can only replace the second version. Also, remember that both synchronized and lock need to operate on an object.

How do I find the install time and date of Windows?

I find the creation date of c:\pagefile.sys can be pretty reliable in most cases. It can easily be obtained using this command (assuming Windows is installed on C:):

dir /as /t:c c:\pagefile.sys

The '/as' specifies 'system files', otherwise it will not be found. The '/t:c' sets the time field to display 'creation'.

Can you append strings to variables in PHP?

This is because PHP uses the period character . for string concatenation, not the plus character +. Therefore to append to a string you want to use the .= operator:

for ($i=1;$i<=100;$i++)
{
    $selectBox .= '<option value="' . $i . '">' . $i . '</option>';
}
$selectBox .= '</select>';

jQuery if statement to check visibility

Yes you can use .is(':visible') in jquery. But while the code is running under the safari browser .is(':visible') is won't work.

So please use the below code

if( $(".example").offset().top > 0 )

The above line will work both IE as well as safari also.

Changing the interval of SetInterval while it's running

(function variableInterval() {
    //whatever needs to be done
    interval *= 2; //deal with your interval
    setTimeout(variableInterval, interval);
    //whatever needs to be done
})();

can't get any shorter

What is limiting the # of simultaneous connections my ASP.NET application can make to a web service?

Have you tried to set the value of the static DefaultConnectionLimit property programmatically?

Here is a good source of information about that true headache... ASP.NET Thread Usage on IIS 7.5, IIS 7.0, and IIS 6.0, with updates for framework 4.0.

Importing modules from parent folder

Here is more generic solution that includes the parent directory into sys.path (works for me):

import os.path, sys
sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), os.pardir))

JPA CascadeType.ALL does not delete orphans

If you are using JPA with EclipseLink, you'll have to set the @PrivateOwned annotation.

Documentation: Eclipse Wiki - Using EclipseLink JPA Extensions - Chapter 1.4 How to Use the @PrivateOwned Annotation

Pure CSS scroll animation

You can use my script from CodePen by just wrapping all the content within a .levit-container DIV.

~function  () {
    function Smooth () {
        this.$container = document.querySelector('.levit-container');
        this.$placeholder = document.createElement('div');
    }

    Smooth.prototype.init = function () {
        var instance = this;

        setContainer.call(instance);
        setPlaceholder.call(instance);
        bindEvents.call(instance);
    }

    function bindEvents () {
        window.addEventListener('scroll', handleScroll.bind(this), false);
    }

    function setContainer () {
        var style = this.$container.style;

        style.position = 'fixed';
        style.width = '100%';
        style.top = '0';
        style.left = '0';
        style.transition = '0.5s ease-out';
    }

    function setPlaceholder () {
        var instance = this,
                $container = instance.$container,
                $placeholder = instance.$placeholder;

        $placeholder.setAttribute('class', 'levit-placeholder');
        $placeholder.style.height = $container.offsetHeight + 'px';
        document.body.insertBefore($placeholder, $container);
    }

    function handleScroll () {
        this.$container.style.transform = 'translateZ(0) translateY(' + (window.scrollY * (- 1)) + 'px)';
    }

    var smooth = new Smooth();
    smooth.init();
}();

https://codepen.io/acauamontiel/pen/zxxebb?editors=0010

How to get Domain name from URL using jquery..?

You don't need jQuery for this, as simple javascript will suffice:

alert(document.domain);

See it in action:

console.log("Output;");  
console.log(location.hostname);
console.log(document.domain);
alert(window.location.hostname)

console.log("document.URL : "+document.URL);
console.log("document.location.href : "+document.location.href);
console.log("document.location.origin : "+document.location.origin);
console.log("document.location.hostname : "+document.location.hostname);
console.log("document.location.host : "+document.location.host);
console.log("document.location.pathname : "+document.location.pathname);

for more details click here window.location

just append "http://" before domain name to get appropriate result.

How do you hide the Address bar in Google Chrome for Chrome Apps?

Visit the site you want in Chrome. Click the Chrome menu in your browser toolbar.

  • Select "More Tools" > "Create shortcut…"
  • Check "Open as window", press "Add"

Once you launch from that shortcut it will be a window without toolbar.

Ways to iterate over a list in Java

In java 8 you can use List.forEach() method with lambda expression to iterate over a list.

import java.util.ArrayList;
import java.util.List;

public class TestA {
    public static void main(String[] args) {
        List<String> list = new ArrayList<String>();
        list.add("Apple");
        list.add("Orange");
        list.add("Banana");
        list.forEach(
                (name) -> {
                    System.out.println(name);
                }
        );
    }
}

nginx error connect to php5-fpm.sock failed (13: Permission denied)

Consideration must also be given to your individual FPM pools, if any.

I couldn't figure out why none of these answers was working for me today. This had been a set-and-forget scenario for me, where I had forgotten that listen.user and listen.group were duplicated on a per-pool basis.

If you used pools for different user accounts like I did, where each user account owns their FPM processes and sockets, setting only the default listen.owner and listen.group configuration options to 'nginx' will simply not work. And obviously, letting 'nginx' own them all is not acceptable either.

For each pool, make sure that

listen.group = nginx

Otherwise, you can leave the pool's ownership and such alone.

jQuery - replace all instances of a character in a string

'some+multi+word+string'.replace(/\+/g, ' ');
                                   ^^^^^^

'g' = "global"

Cheers

REST API error code 500 handling

You suggested "Catching any unexpected errors and return some error code signaling "unexpected situation" " but couldn't find an appropriate error code.

Guess what: That's what 5xx is there for.

iOS change navigation bar title font and color

For Objective-C to set Font and Color

- (void)_setup {
    NSDictionary *barButtonTitleAttributes = @{
                                               NSForegroundColorAttributeName : [UIColor whiteColor],
                                               NSFontAttributeName :[UIFont fontWithName:@"Lato-Regular" size:15.0]
                                               };
    [self.navigationBar setTitleTextAttributes:barButtonTitleAttributes];

}

Google access token expiration time

Since there is no accepted answer I will try to answer this one:

[s] - seconds

Difference between HashSet and HashMap?

Differences between HashSet and HashMap in Java

1) First and most significant difference between HashMap and HashSet is that HashMap is an implementation of Map interface while HashSet is an implementation of Set interface, which means HashMap is a key value based data-structure and HashSet guarantees uniqueness by not allowing duplicates.In reality HashSet is a wrapper around HashMap in Java, if you look at the code of add(E e) method of HashSet.java you will see following code :

public boolean add(E e) 
{
    return map.put(e, PRESENT)==null;
}

where its putting Object into map as key and value is an final object PRESENT which is dummy.

2) Second difference between HashMap and HashSet is that , we use add() method to put elements into Set but we use put() method to insert key and value into HashMap in Java.

3) HashSet allows only one null key, but HashMap can allow one null key + multiple null values.

That's all on difference between HashSet and HashMap in Java. In summary HashSet and HashMap are two different type of Collection one being Set and other being Map.

Post request with Wget?

Wget currently only supports x-www-form-urlencoded data. --post-file is not for transmitting files as form attachments, it expects data with the form: key=value&otherkey=example.

--post-data and --post-file work the same way: the only difference is that --post-data allows you to specify the data in the command line, while --post-file allows you to specify the path of the file that contain the data to send.

Here's the documentation:

 --post-data=string
       --post-file=file
           Use POST as the method for all HTTP requests and send the specified data
           in the request body.  --post-data sends string as data, whereas
           --post-file sends the contents of file.  Other than that, they work in
           exactly the same way. In particular, they both expect content of the
           form "key1=value1&key2=value2", with percent-encoding for special
           characters; the only difference is that one expects its content as a
           command-line parameter and the other accepts its content from a file. In
           particular, --post-file is not for transmitting files as form
           attachments: those must appear as "key=value" data (with appropriate
           percent-coding) just like everything else. Wget does not currently
           support "multipart/form-data" for transmitting POST data; only
           "application/x-www-form-urlencoded". Only one of --post-data and
           --post-file should be specified.

Regarding your authentication token, it should either be provided in the header, in the path of the url, or in the data itself. This must be indicated somewhere in the documentation of the service you use. In a POST request, as in a GET request, you must specify the data using keys and values. This way the server will be able to receive multiple information with specific names. It's similar with variables.

Hence, you can't just send a magic token to the server, you also need to specify the name of the key. If the key is "token", then it should be token=YOUR_TOKEN.

wget --post-data 'user=foo&password=bar' http://example.com/auth.php

Also, you should consider using curl if you can because it is easier to send files using it. There are many examples on the Internet for that.

Spring JPA @Query with LIKE

You Missed a colon(:) before the username parameter. therefore your code must change from:

@Query("select u from user u where u.username like '%username%'")

to :

@Query("select u from user u where u.username like '%:username%'")

Android Facebook integration with invalid key hash

What Facebook used is not the default password and alias for debug. You need to change it following and it will work.

/usr/lib/jvm/jdk1.8.0_66/bin/keytool -exportcert -alias androiddebugkey -keystore ~/.android/debug.keystore | openssl sha1 -binary | openssl base64

If you have not changed anything with the default password it should be "android".

You can also configure it in the build.gradle file. But the same alias password should be used for generating the hash:

android {
    signingConfigs {
        release {
            storeFile file("~/.android/debug.keystore")
            storePassword "android"
            keyAlias "androiddebugkey"
            keyPassword "android"
        }
    }
}

Name node is in safe mode. Not able to leave

The Command did not work for me but the following did

hdfs dfsadmin -safemode leave

I used the hdfs command instead of the hadoop command.

Check out http://ask.gopivotal.com/hc/en-us/articles/200933026-HDFS-goes-into-readonly-mode-and-errors-out-with-Name-node-is-in-safe-mode- link too

How does @synchronized lock/unlock in Objective-C?

Actually

{
  @synchronized(self) {
    return [[myString retain] autorelease];
  }
}

transforms directly into:

// needs #import <objc/objc-sync.h>
{
  objc_sync_enter(self)
    id retVal = [[myString retain] autorelease];
  objc_sync_exit(self);
  return retVal;
}

This API available since iOS 2.0 and imported using...

#import <objc/objc-sync.h>

Create a new Ruby on Rails application using MySQL instead of SQLite

database.yml

# MySQL. Versions 5.1.10 and up are supported.
#
# Install the MySQL driver
#   gem install mysql2
#
# Ensure the MySQL gem is defined in your Gemfile
#   gem 'mysql2'
#
# And be sure to use new-style password hashing:
#   https://dev.mysql.com/doc/refman/5.7/en/password-hashing.html
#
default: &default
  adapter: mysql2
  encoding: utf8
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
  host: localhost
  database: database_name
  username: username
  password: secret

development:
  <<: *default

# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
  <<: *default

# As with config/secrets.yml, you never want to store sensitive information,
# like your database password, in your source code. If your source code is
# ever seen by anyone, they now have access to your database.
#
# Instead, provide the password as a unix environment variable when you boot
# the app. Read http://guides.rubyonrails.org/configuring.html#configuring-a-database
# for a full rundown on how to provide these environment variables in a
# production deployment.
#
# On Heroku and other platform providers, you may have a full connection URL
# available as an environment variable. For example:
#
#   DATABASE_URL="mysql2://myuser:mypass@localhost/somedatabase"
#
# You can use this database configuration with:
#
#   production:
#     url: <%= ENV['DATABASE_URL'] %>
#
production:
  <<: *default

Gemfile:

# Use mysql as the database for Active Record
gem 'mysql2', '>= 0.4.4', '< 0.6.0'

JavaScript alert box with timer

tooltips can be used as alerts. These can be timed to appear and disappear.

CSS can be used to create tooltips and menus. More info on this can be found in 'Javascript for Dummies'. Sorry about the label of this book... Not infuring anything.

Reading other peoples answers here, I realized the answer to my own thoughts/questions. SetTimeOut could be applied to tooltips. Javascript could trigger them.

Read a file one line at a time in node.js?

Since Node.js v0.12 and as of Node.js v4.0.0, there is a stable readline core module. Here's the easiest way to read lines from a file, without any external modules:

const fs = require('fs');
const readline = require('readline');

async function processLineByLine() {
  const fileStream = fs.createReadStream('input.txt');

  const rl = readline.createInterface({
    input: fileStream,
    crlfDelay: Infinity
  });
  // Note: we use the crlfDelay option to recognize all instances of CR LF
  // ('\r\n') in input.txt as a single line break.

  for (const line of rl) {
    // Each line in input.txt will be successively available here as `line`.
    console.log(`Line from file: ${line}`);
  }
}

processLineByLine();

Or alternatively:

var lineReader = require('readline').createInterface({
  input: require('fs').createReadStream('file.in')
});

lineReader.on('line', function (line) {
  console.log('Line from file:', line);
});

The last line is read correctly (as of Node v0.12 or later), even if there is no final \n.

UPDATE: this example has been added to Node's API official documentation.

Capitalize first letter. MySQL

UPDATE tb_Company SET CompanyIndustry = UCASE(LEFT(CompanyIndustry, 1)) + 
SUBSTRING(CompanyIndustry, 2, LEN(CompanyIndustry))

use mysql SUM() in a WHERE clause

When using aggregate functions to filter, you must use a HAVING statement.

SELECT *
FROM tblMoney
HAVING Sum(CASH) > 500

How to format a duration in java? (e.g format H:MM:SS)

I'm not sure that is you want, but check this Android helper class

import android.text.format.DateUtils

For example: DateUtils.formatElapsedTime()

Javascript / Chrome - How to copy an object from the webkit inspector as code

You can copy an object to your clip board using copy(JSON.stringify(Object_Name)); in the console.

Eg:- Copy & Paste the below code in your console and press ENTER. Now, try to paste(CTRL+V for Windows or CMD+V for mac) it some where else and you will get {"name":"Daniel","age":25}

var profile = {
    name: "Daniel",
    age: 25
};

copy(JSON.stringify(profile));

jQuery Ajax requests are getting cancelled without being sent

I have had the same problem, for me I was creating the iframe for temporary manner and I was removing the iframe before the ajax become completes, so the browser would cancel my ajax request.

How to select a value in dropdown javascript?

Yes. As mentioned in the posts, value property is nonstandard and does not work with IE. You will need to use the selectedIndex property to achieve this. You can refer to the w3schools DOM reference to see the properties of HTML elements. The following link will give you the list of properties you can work with on the select element.

http://www.w3schools.com/jsref/dom_obj_select.asp

Update

This was not supported during 2011 on IE. As commented by finnTheHuman, it is supported at present.

Tomcat started in Eclipse but unable to connect to http://localhost:8085/

You can change the port number:

Open the server tab in eclipse -> right click open click on open---->you can change the port number.

Run the application with http://localhost:8080/Applicationname it will give output and also check http://localhost:8080/Applicationname/index.jsp

How to remove a character at the end of each line in unix

An awk code based on RS.

awk '1' RS=',\n' file

or:

awk 'BEGIN{RS=",\n"}1' file

This last example will be valid for any char before newline:

awk '1' RS='.\n' file

Note: dot . matches any character except line breaks.

Explanation

awk allows us to use different record (line) regex separators, we just need to include the comma before the line break (or dot for any char) in the one used for the input, the RS.

Note: what that 1 means?

Short answer, It's just a shortcut to avoid using the print statement. In awk when a condition gets matched the default action is to print the input line, example:

$ echo "test" |awk '1'
test

That's because 1 will be always true, so this expression is equivalent to:

$ echo "test"|awk '1==1'
test
$ echo "test"|awk '{if (1==1){print}}'
test

Documentation

Check Record Splitting with Standard awk and Output Separators.

Keep a line of text as a single line - wrap the whole line or none at all

You could also put non-breaking spaces (&nbsp;) in lieu of the spaces so that they're forced to stay together.

How do I wrap this line of text
-&nbsp;asked&nbsp;by&nbsp;Peter&nbsp;2&nbsp;days&nbsp;ago

How to find the 'sizeof' (a pointer pointing to an array)?

For dynamic arrays (malloc or C++ new) you need to store the size of the array as mentioned by others or perhaps build an array manager structure which handles add, remove, count, etc. Unfortunately C doesn't do this nearly as well as C++ since you basically have to build it for each different array type you are storing which is cumbersome if you have multiple types of arrays that you need to manage.

For static arrays, such as the one in your example, there is a common macro used to get the size, but it is not recommended as it does not check if the parameter is really a static array. The macro is used in real code though, e.g. in the Linux kernel headers although it may be slightly different than the one below:

#if !defined(ARRAY_SIZE)
    #define ARRAY_SIZE(x) (sizeof((x)) / sizeof((x)[0]))
#endif

int main()
{
    int days[] = {1,2,3,4,5};
    int *ptr = days;
    printf("%u\n", ARRAY_SIZE(days));
    printf("%u\n", sizeof(ptr));
    return 0;
}

You can google for reasons to be wary of macros like this. Be careful.

If possible, the C++ stdlib such as vector which is much safer and easier to use.

What is the size of ActionBar in pixels?

To retrieve the height of the ActionBar in XML, just use

?android:attr/actionBarSize

or if you're an ActionBarSherlock or AppCompat user, use this

?attr/actionBarSize

If you need this value at runtime, use this

final TypedArray styledAttributes = getContext().getTheme().obtainStyledAttributes(
                    new int[] { android.R.attr.actionBarSize });
mActionBarSize = (int) styledAttributes.getDimension(0, 0);
styledAttributes.recycle();

If you need to understand where this is defined:

  1. The attribute name itself is defined in the platform's /res/values/attrs.xml
  2. The platform's themes.xml picks this attribute and assigns a value to it.
  3. The value assigned in step 2 depends on different device sizes, which are defined in various dimens.xml files in the platform, ie. core/res/res/values-sw600dp/dimens.xml

Get Client Machine Name in PHP

What's this "other information"? An IP address?

In PHP, you use $_SERVER['REMOTE_ADDR'] to get the IP address of the remote client, then you can use gethostbyaddr() to try and conver that IP into a hostname - but not all IPs have a reverse mapping configured.

Force browser to clear cache

Do you want to clear the cache, or just make sure your current (changed?) page is not cached?

If the latter, it should be as simple as

<META HTTP-EQUIV="Pragma" CONTENT="no-cache">

Make a dictionary in Python from input values

This is what we ended up using:

n = 3
d = dict(raw_input().split() for _ in range(n))
print d

Input:

A1023 CRT
A1029 Regulator
A1030 Therm

Output:

{'A1023': 'CRT', 'A1029': 'Regulator', 'A1030': 'Therm'}

HashSet vs LinkedHashSet

I suggest you to use LinkedHashSet most of the time, because it has better performance overall):

  1. Predictable iteration order LinkedHashSet (Oracle)
  2. LinkedHashSet is more expensive for insertions than HashSet;
  3. In general slightly better performance than HashMap, because the most of the time we use Set structures for iterating.

Performance tests:

------------- TreeSet -------------
 size       add  contains   iterate
   10       746       173        89
  100       501       264        68
 1000       714       410        69
10000      1975       552        69
------------- HashSet -------------
 size       add  contains   iterate
   10       308        91        94
  100       178        75        73
 1000       216       110        72
10000       711       215       100
---------- LinkedHashSet ----------
 size       add  contains   iterate
   10       350        65        83
  100       270        74        55
 1000       303       111        54
10000      1615       256        58

You can see source test page here: The Final Performance Testing Example

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

Java 9 JDK 9.0.4

  1. Go to the top left corner of Android Studio (4.1.1)-> click on File
  2. Click on Setting
  3. Click on Build, Execution, Deployment
  4. Click on Compiler
  5. Click on Kotlin Compiler
  6. Target JVM version

File | Settings | Build, Execution, Deployment | Compiler | Kotlin Compiler

Difference between Python's Generators and Iterators

iterator is a more general concept: any object whose class has a __next__ method (next in Python 2) and an __iter__ method that does return self.

Every generator is an iterator, but not vice versa. A generator is built by calling a function that has one or more yield expressions (yield statements, in Python 2.5 and earlier), and is an object that meets the previous paragraph's definition of an iterator.

You may want to use a custom iterator, rather than a generator, when you need a class with somewhat complex state-maintaining behavior, or want to expose other methods besides __next__ (and __iter__ and __init__). Most often, a generator (sometimes, for sufficiently simple needs, a generator expression) is sufficient, and it's simpler to code because state maintenance (within reasonable limits) is basically "done for you" by the frame getting suspended and resumed.

For example, a generator such as:

def squares(start, stop):
    for i in range(start, stop):
        yield i * i

generator = squares(a, b)

or the equivalent generator expression (genexp)

generator = (i*i for i in range(a, b))

would take more code to build as a custom iterator:

class Squares(object):
    def __init__(self, start, stop):
       self.start = start
       self.stop = stop
    def __iter__(self): return self
    def __next__(self): # next in Python 2
       if self.start >= self.stop:
           raise StopIteration
       current = self.start * self.start
       self.start += 1
       return current

iterator = Squares(a, b)

But, of course, with class Squares you could easily offer extra methods, i.e.

    def current(self):
       return self.start

if you have any actual need for such extra functionality in your application.

Why does my JavaScript code receive a "No 'Access-Control-Allow-Origin' header is present on the requested resource" error, while Postman does not?

If you want to bypass that restriction when fetching the contents with fetch API or XMLHttpRequest in javascript, you can use a proxy server so that it sets the header Access-Control-Allow-Origin to *.

const express = require('express');
const request = require('request');

const app = express();

app.use((req, res, next) => {
  res.header('Access-Control-Allow-Origin', '*');
  next();
});

app.get('/fetch', (req, res) => {
  request(
    { url: req.query.url },
    (error, response, body) => {
      if (error || response.statusCode !== 200) {
        return res.status(500).send('error');
      }
      res.send(body);
    }
  )
});

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => console.log(`listening on ${PORT}`));

Above is a sample code( node Js required ) which can act as a proxy server. For eg: If I want to fetch https://www.google.com normally a CORS error is thrown, but now since the request is sent through the proxy server hosted locally at port 3000, the proxy server adds the Access-Control-Allow-Origin header in the response and there wont be any issue.

Send a GET request to http://localhost:3000/fetch?url=Your URL here , instead of directly sending the request to the URl you want to fetch.

Your URL here stands for the URL you wish to fetch eg: https://www.google.com

Force sidebar height 100% using CSS (with a sticky bottom image)?

I realise this is an old post but I was trying to work something out for my site to have a sidebar. Would this work?

#sidebar-background
{
    position:fixed;
    width:250px;
    top:0;
    bottom:0;
    background-color:orange;
}

#content-background
{
    position:fixed;
    right:0;
    top:0;
    bottom:0;
    left:250px;
    background-color:pink;
}

#sidebar
{
    float:left;
    width:250px;
}

#content
{
    float:left;
    width:600px;
}

<div id="sidebar-background"></div>
<div id="content-background"></div>

<div id="sidebar">Sidebar stuff here</div>
<div id="content">Stuff in here</div>

Build project into a JAR automatically in Eclipse

This is possible by defining a custom Builder in eclipse (see the link in Peter's answer). However, unless your project is very small, it may slow down your workspace unacceptably. Autobuild for class files happens incrementally, i.e. only those classes affected by a change are recompiled, but the JAR file will have to be rebuilt and copied completely, every time you save a change.

Why doesn't importing java.util.* include Arrays and Lists?

Take a look at this forum http://htmlcoderhelper.com/why-is-using-a-wild-card-with-a-java-import-statement-bad/. Theres a discussion on how using wildcards can lead to conflicts if you add new classes to the packages and if there are two classes with the same name in different packages where only one of them will be imported.

Update


It gives that warning because your the line should actually be

List<Integer> i = new ArrayList<Integer>(Arrays.asList(0,1,2,3,4,5,6,7,8,9,10));
List<Integer> j = new ArrayList<Integer>();

You need to specify the type for array list or the compiler will give that warning because it cannot identify that you are using the list in a type safe way.

excel vba getting the row,cell value from selection.address

Dim f as Range

Set f=ActiveSheet.Cells.Find(...)

If Not f Is Nothing then
    msgbox "Row=" & f.Row & vbcrlf & "Column=" & f.Column
Else
    msgbox "value not found!"
End If

jQuery scroll to ID from different page

On the link put a hash:

<a href="otherpage.html#elementID">Jump</a>

And on other page, you can do:

$('html,body').animate({
  scrollTop: $(window.location.hash).offset().top
});

On other page, you should have element with id set to elementID to scroll to. Of course you can change the name of it.

How to check a channel is closed or not without reading it?

Well, you can use default branch to detect it, for a closed channel will be selected, for example: the following code will select default, channel, channel, the first select is not blocked.

func main() {
    ch := make(chan int)

    go func() {
        select {
        case <-ch:
            log.Printf("1.channel")
        default:
            log.Printf("1.default")
        }
        select {
        case <-ch:
            log.Printf("2.channel")
        }
        close(ch)
        select {
        case <-ch:
            log.Printf("3.channel")
        default:
            log.Printf("3.default")
        }
    }()
    time.Sleep(time.Second)
    ch <- 1
    time.Sleep(time.Second)
}

Prints

2018/05/24 08:00:00 1.default
2018/05/24 08:00:01 2.channel
2018/05/24 08:00:01 3.channel

How to override the properties of a CSS class using another CSS class

LIFO is the way browser parses CSS properties..If you are using Sass declare a variable called as

"$header-background: red;"

use it instead of directly assigning values like red or blue. When you want to override just reassign the value to

"$header-background:blue"

then

background-color:$header-background;

it should smoothly override. Using "!important" is not always the right choice..Its just a hotfix

Datatype for storing ip address in SQL Server

The technically correct way to store IPv4 is binary(4), since that is what it actually is (no, not even an INT32/INT(4), the numeric textual form that we all know and love (255.255.255.255) being just the display conversion of its binary content).

If you do it this way, you will want functions to convert to and from the textual-display format:

Here's how to convert the textual display form to binary:

CREATE FUNCTION dbo.fnBinaryIPv4(@ip AS VARCHAR(15)) RETURNS BINARY(4)
AS
BEGIN
    DECLARE @bin AS BINARY(4)

    SELECT @bin = CAST( CAST( PARSENAME( @ip, 4 ) AS INTEGER) AS BINARY(1))
                + CAST( CAST( PARSENAME( @ip, 3 ) AS INTEGER) AS BINARY(1))
                + CAST( CAST( PARSENAME( @ip, 2 ) AS INTEGER) AS BINARY(1))
                + CAST( CAST( PARSENAME( @ip, 1 ) AS INTEGER) AS BINARY(1))

    RETURN @bin
END
go

And here's how to convert the binary back to the textual display form:

CREATE FUNCTION dbo.fnDisplayIPv4(@ip AS BINARY(4)) RETURNS VARCHAR(15)
AS
BEGIN
    DECLARE @str AS VARCHAR(15) 

    SELECT @str = CAST( CAST( SUBSTRING( @ip, 1, 1) AS INTEGER) AS VARCHAR(3) ) + '.'
                + CAST( CAST( SUBSTRING( @ip, 2, 1) AS INTEGER) AS VARCHAR(3) ) + '.'
                + CAST( CAST( SUBSTRING( @ip, 3, 1) AS INTEGER) AS VARCHAR(3) ) + '.'
                + CAST( CAST( SUBSTRING( @ip, 4, 1) AS INTEGER) AS VARCHAR(3) );

    RETURN @str
END;
go

Here's a demo of how to use them:

SELECT dbo.fnBinaryIPv4('192.65.68.201')
--should return 0xC04144C9
go

SELECT dbo.fnDisplayIPv4( 0xC04144C9 )
-- should return '192.65.68.201'
go

Finally, when doing lookups and compares, always use the binary form if you want to be able to leverage your indexes.


UPDATE:

I wanted to add that one way to address the inherent performance problems of scalar UDFs in SQL Server, but still retain the code-reuse of a function is to use an iTVF (inline table-valued function) instead. Here's how the first function above (string to binary) can be re-written as an iTVF:

CREATE FUNCTION dbo.itvfBinaryIPv4(@ip AS VARCHAR(15)) RETURNS TABLE
AS RETURN (
    SELECT CAST(
               CAST( CAST( PARSENAME( @ip, 4 ) AS INTEGER) AS BINARY(1))
            +  CAST( CAST( PARSENAME( @ip, 3 ) AS INTEGER) AS BINARY(1))
            +  CAST( CAST( PARSENAME( @ip, 2 ) AS INTEGER) AS BINARY(1))
            +  CAST( CAST( PARSENAME( @ip, 1 ) AS INTEGER) AS BINARY(1))
                AS BINARY(4)) As bin
        )
go

Here's it in the example:

SELECT bin FROM dbo.fnBinaryIPv4('192.65.68.201')
--should return 0xC04144C9
go

And here's how you would use it in an INSERT

INSERT INTo myIpTable
SELECT {other_column_values,...},
       (SELECT bin FROM dbo.itvfBinaryIPv4('192.65.68.201'))

Reshape an array in NumPy

a = np.arange(18).reshape(9,2)
b = a.reshape(3,3,2).swapaxes(0,2)

# a: 
array([[ 0,  1],
       [ 2,  3],
       [ 4,  5],
       [ 6,  7],
       [ 8,  9],
       [10, 11],
       [12, 13],
       [14, 15],
       [16, 17]])


# b:
array([[[ 0,  6, 12],
        [ 2,  8, 14],
        [ 4, 10, 16]],

       [[ 1,  7, 13],
        [ 3,  9, 15],
        [ 5, 11, 17]]])

Real mouse position in canvas

The easiest way to compute the correct mouse click or mouse move position on a canvas event is to use this little equation:

canvas.addEventListener('click', event =>
{
    let bound = canvas.getBoundingClientRect();

    let x = event.clientX - bound.left - canvas.clientLeft;
    let y = event.clientY - bound.top - canvas.clientTop;

    context.fillRect(x, y, 16, 16);
});

If the canvas has padding-left or padding-top, subtract x and y via:

x -= parseFloat(style['padding-left'].replace('px'));
y -= parseFloat(style['padding-top'].replace('px'));

Change connection string & reload app.config at run time

Yeah, when ASP.NET web.config gets updated, the whole application gets restarted which means the web.config gets reloaded.

Why does git say "Pull is not possible because you have unmerged files"?

When a merge conflict occurs , you can open individual file. You will get "<<<<<<< or >>>>>>>" symbols. These refer to your changes and the changes present on remote. You can manually edit the part that is requires. after that save the file and then do : git add

The merge conflicts will be resolved.

Fastest way to copy a file in Node.js

For fast copies you should use the fs.constants.COPYFILE_FICLONE flag. It allows (for filesystems that support this) to not actually copy the content of the file. Just a new file entry is created, but it points to a Copy-on-Write "clone" of the source file.

To do nothing/less is the fastest way of doing something ;)

https://nodejs.org/api/fs.html#fs_fs_copyfile_src_dest_flags_callback

let fs = require("fs");

fs.copyFile(
  "source.txt",
  "destination.txt",
  fs.constants.COPYFILE_FICLONE,
  (err) => {
    if (err) {
      // TODO: handle error
      console.log("error");
    }
    console.log("success");
  }
);

Using promises instead:

let fs = require("fs");
let util = require("util");
let copyFile = util.promisify(fs.copyFile);


copyFile(
  "source.txt",
  "destination.txt",
  fs.constants.COPYFILE_FICLONE
)
  .catch(() => console.log("error"))
  .then(() => console.log("success"));

Get ID from URL with jQuery

const url = "http://www.example.com/1234"
const id = url.split('/').pop();

Try this, it is much easier

The output gives 1234

Can a Byte[] Array be written to a file in C#?

You can use the FileStream.Write(byte[] array, int offset, int count) method to write it out.

If your array name is "myArray" the code would be.

myStream.Write(myArray, 0, myArray.count);

How to do jquery code AFTER page loading?

Following

$(document).ready(function() { 
});

can be replaced

$(window).bind("load", function() { 
     // insert your code here 
});

There is once more way which i'm using to increase the page load time.

$(document).ready(function() { 
  $(window).load(function() { 
     //insert all your ajax callback code here. 
     //Which will run only after page is fully loaded in background.
  });
});

Find out which remote branch a local branch is tracking

You can use git checkout, i.e. "check out the current branch". This is a no-op with a side-effects to show the tracking information, if exists, for the current branch.

$ git checkout 
Your branch is up-to-date with 'origin/master'.

Why does modulus division (%) only work with integers?

The % operator does not work in C++, when you are trying to find the remainder of two numbers which are both of the type Float or Double.

Hence you could try using the fmod function from math.h / cmath.h or you could use these lines of code to avoid using that header file:

float sin(float x) {
 float temp;
 temp = (x + M_PI) / ((2 *M_PI) - M_PI);
 return limited_sin((x + M_PI) - ((2 *M_PI) - M_PI) * temp ));

}

How to do a less than or equal to filter in Django queryset?

Less than or equal:

User.objects.filter(userprofile__level__lte=0)

Greater than or equal:

User.objects.filter(userprofile__level__gte=0)

Likewise, lt for less than and gt for greater than. You can find them all in the documentation.

Calling Non-Static Method In Static Method In Java

The easiest way to use a non-static method/field within a a static method or vice versa is...

(To work this there must be at least one instance of this class)

This type of situation is very common in android app development eg:- An Activity has at-least one instance.

public class ParentClass{

private static ParentClass mParentInstance = null;

ParentClass(){
  mParentInstance = ParentClass.this;           
}


void instanceMethod1(){
}


static void staticMethod1(){        
    mParentInstance.instanceMethod1();
}


public static class InnerClass{
      void  innerClassMethod1(){
          mParentInstance.staticMethod1();
          mParentInstance.instanceMethod1();
      }
   }
}

Note:- This cannot be used as a builder method like this one.....

String.valueOf(100);

Twitter bootstrap collapse: change display of toggle button

You do like this. the function return the old text.

$('button').click(function(){ 
        $(this).text(function(i,old){
            return old=='Read More' ?  'Read Less' : 'Read More';
        });
    });

Web Application Problems (web.config errors) HTTP 500.19 with IIS7.5 and ASP.NET v2

I got this error by putting the <customErrors> tag inside of <system.webServer> instead of <system.web> where it belongs. There was a little squiggle under the <customErrors> tag but I didn't notice it right away.

getting the ng-object selected with ng-change

You can also directly get selected value using following code

 <select ng-options='t.name for t in templates'
                  ng-change='selectedTemplate(t.url)'></select>

script.js

 $scope.selectedTemplate = function(pTemplate) {
    //Your logic
    alert('Template Url is : '+pTemplate);
}

How to apply a CSS filter to a background image

Although all the solutions mentioned are very clever, all seemed to have minor issues or potential knock on effects with other elements on the page when I tried them.

In the end to save time I simply went back to my old solution: I used Paint.NET and went to Effects, Gaussian Blur with a radius 5 to 10 pixels and just saved that as the page image. :-)

HTML:

<body class="mainbody">
</body

CSS:

body.mainbody
{
    background: url('../images/myphoto.blurred.png');
    -moz-background-size: cover;
    -webkit-background-size: cover;
    background-size: cover;
    background-position: top center !important;
    background-repeat: no-repeat !important;
    background-attachment: fixed;
}

EDIT:

I finally got it working, but the solution is by no means straightforward! See here:

Create SQL script that create database and tables

In SQL Server Management Studio you can right click on the database you want to replicate, and select "Script Database as" to have the tool create the appropriate SQL file to replicate that database on another server. You can repeat this process for each table you want to create, and then merge the files into a single SQL file. Don't forget to add a using statement after you create your Database but prior to any table creation.

In more recent versions of SQL Server you can get this in one file in SSMS.

  1. Right click a database.
  2. Tasks
  3. Generate Scripts

This will launch a wizard where you can script the entire database or just portions. There does not appear to be a T-SQL way of doing this.

Generate SQL Server Scripts

how to display a div triggered by onclick event

function showstuff(boxid){
   document.getElementById(boxid).style.visibility="visible";
}
<button onclick="showstuff('id_to_show');" />

This will help you, I think.

How to remove an element slowly with jQuery?

All the answers are good, but I found they all lacked that professional "polish".

I came up with this, fading out, sliding up, then removing:

$target.fadeTo(1000, 0.01, function(){ 
    $(this).slideUp(150, function() {
        $(this).remove(); 
    }); 
});

How do you strip a character out of a column in SQL Server?

Use the "REPLACE" string function on the column in question:

UPDATE (yourTable)
SET YourColumn = REPLACE(YourColumn, '*', '')
WHERE (your conditions)

Replace the "*" with the character you want to strip out and specify your WHERE clause to match the rows you want to apply the update to.

Of course, the REPLACE function can also be used - as other answerer have shown - in a SELECT statement - from your question, I assumed you were trying to update a table.

Marc

Check if a file exists in jenkins pipeline

You need to use brackets when using the fileExists step in an if condition or assign the returned value to a variable

Using variable:

def exists = fileExists 'file'

if (exists) {
    echo 'Yes'
} else {
    echo 'No'
}

Using brackets:

if (fileExists('file')) {
    echo 'Yes'
} else {
    echo 'No'
}

Execute a batch file on a remote PC using a batch file on local PC

While I would recommend against this.

But you can use shutdown as client if the target machine has remote shutdown enabled and is in the same workgroup.

Example:

shutdown.exe /s /m \\<target-computer-name> /t 00

replacing <target-computer-name> with the URI for the target machine,

Otherwise, if you want to trigger this through Apache, you'll need to configure the batch script as a CGI script by putting AddHandler cgi-script .bat and Options +ExecCGI into either a local .htaccess file or in the main configuration for your Apache install.

Then you can just call the .bat file containing the shutdown.exe command from your browser.

How to remove specific object from ArrayList in Java?

AValchev is right. A quicker solution would be to parse all elements and compare by an unique property.

String property = "property to delete";

for(int j = 0; j < i.size(); j++)
{
    Student obj = i.get(j);

    if(obj.getProperty().equals(property)){
       //found, delete.
        i.remove(j);
        break;
    }

}

THis is a quick solution. You'd better implement object comparison for larger projects.

What are DDL and DML?

DDL

Create,Alter,Drop of (Databases,Tables,Keys,Index,Views,Functions,Stored Procedures)

DML

Insert ,Delete,Update,Truncate of (Tables)

HTTP Status 405 - Method Not Allowed Error for Rest API

I also had this problem and was able to solve it by enabling CORS support on the server. In my case it was an Azure server and it was easy: Enable CORS on Azure

So check for your server how it works and enable CORS. I didn't even need a browser plugin or proxy :)

mysql - move rows from one table to another

A simple INSERT INTO SELECT statement:

INSERT INTO persons_table SELECT * FROM customer_table WHERE person_name = 'tom';

DELETE FROM customer_table WHERE person_name = 'tom';

How to disable/enable select field using jQuery?

Use the following:

$("select").attr("disabled", "disabled");

Or simply add id="pizza_kind" to <select> tag, like <select name="pizza_kind" id="pizza_kind">: jsfiddle link

The reason your code didn't work is simply because $("#pizza_kind") isn't selecting the <select> element because it does not have id="pizza_kind".

Edit: actually, a better selector is $("select[name='pizza_kind']"): jsfiddle link

Turn Pandas Multi-Index into column

This doesn't really apply to your case but could be helpful for others (like myself 5 minutes ago) to know. If one's multindex have the same name like this:

                         value
Trial        Trial
    1              0        13
                   1         3
                   2         4
    2              0       NaN
                   1        12
    3              0        34 

df.reset_index(inplace=True) will fail, cause the columns that are created cannot have the same names.

So then you need to rename the multindex with df.index = df.index.set_names(['Trial', 'measurement']) to get:

                           value
Trial    measurement       

    1              0        13
    1              1         3
    1              2         4
    2              0       NaN
    2              1        12
    3              0        34 

And then df.reset_index(inplace=True) will work like a charm.

I encountered this problem after grouping by year and month on a datetime-column(not index) called live_date, which meant that both year and month were named live_date.

How to force a hover state with jQuery?

I think the best solution I have come across is on this stackoverflow. This short jQuery code allows all your hover effects to show on click or touch..
No need to add anything within the function.

$('body').on('touchstart', function() {});

Hope this helps.

Get pixel color from canvas, on mousemove

I have a very simple working example of geting pixel color from canvas.

First some basic HTML:

<canvas id="myCanvas" width="400" height="250" style="background:red;" onmouseover="echoColor(event)">
</canvas>

Then JS to draw something on the Canvas, and to get color:

var c = document.getElementById("myCanvas");
var ctx = c.getContext("2d");
ctx.fillStyle = "black";
ctx.fillRect(10, 10, 50, 50);

function echoColor(e){
    var imgData = ctx.getImageData(e.pageX, e.pageX, 1, 1);
    red = imgData.data[0];
    green = imgData.data[1];
    blue = imgData.data[2];
    alpha = imgData.data[3];
    console.log(red + " " + green + " " + blue + " " + alpha);  
}

Here is a working example, just look at the console.

Git:nothing added to commit but untracked files present

Follow all the steps.

Step 1: initialize git

$ git init

Step 2: Check files are exist or not.

$git ls

Step 3 : Add the file

$git add filename

Step 4: Add comment to show

$git commit -m "your comment"

Step 5: Link to your repository

$git remote add origin  "copy repository link  and paste here"

Step 6: Push on Git

$ git push -u origin master

Difference between Big-O and Little-O Notation

In general

Asymptotic notation is something you can understand as: how do functions compare when zooming out? (A good way to test this is simply to use a tool like Desmos and play with your mouse wheel). In particular:

  • f(n) ? o(n) means: at some point, the more you zoom out, the more f(n) will be dominated by n (it will progressively diverge from it).
  • g(n) ? T(n) means: at some point, zooming out will not change how g(n) compare to n (if we remove ticks from the axis you couldn't tell the zoom level).

Finally h(n) ? O(n) means that function h can be in either of these two categories. It can either look a lot like n or it could be smaller and smaller than n when n increases. Basically, both f(n) and g(n) are also in O(n).

In computer science

In computer science, people will usually prove that a given algorithm admits both an upper O and a lower bound . When both bounds meet that means that we found an asymptotically optimal algorithm to solve that particular problem.

For example, if we prove that the complexity of an algorithm is both in O(n) and (n) it implies that its complexity is in T(n). That's the definition of T and it more or less translates to "asymptotically equal". Which also means that no algorithm can solve the given problem in o(n). Again, roughly saying "this problem can't be solved in less than n steps".

An upper bound of O(n) simply means that even in the worse case, the algorithm will terminate in at most n steps (ignoring all constant factors, both multiplicative and additive). A lower bound of (n) means on the opposite that we built some examples where the problem solved by this algorithm couldn't be solved in less than n steps (again ignoring multiplicative and additive constants). The number of steps is at most n and at least n so this problem complexity is "exactly n". Instead of saying "ignoring constant multiplicative/additive factor" every time we just write T(n) for short.

One-liner if statements, how to convert this if-else-statement

If expression returns a boolean, you can just return the result of it.

Example

 return (a > b)

How to add bootstrap to an angular-cli project

Good News! Basically, Bootstrap 5 can be implemented easily now, and you don't even need jQuery.
From your terminal, just run

npm install bootstrap@next --save

So, Angular uses webpack, therefore, in your app.module.ts, just add:

import "bootstrap";

Or if you want to import them separately, do it like:

import { ModuleToBeImported } from 'bootstrap';

Then to your styles.scss, add:

@import '~bootstrap/scss/bootstrap';

Basically that's it, BUT beware that some components require popper.js. Components requiring bootstrap's js There you'll see the components dependent on popper.js too, which at the time of writing this are Dropdowns for displaying and positioning, and Tooltips and popovers for displaying and positioning.

Therefore, to install popper.js, just run:

npm install @popperjs/core

Reference

Getting android.content.res.Resources$NotFoundException: exception even when the resource is present in android

This can happen due to a different language in the phone for which your code doesn't have the asset for. For example your preference.xml is placed in xml-en and you are trying to run your app in a phone which has French selected, the app will crash.

How to enable copy paste from between host machine and virtual machine in vmware, virtual machine is ubuntu

Here is a small hint that I hope might be useful to other poor saps that experienced the same issue as I did.

My Setup: Host: Windows 7 Enterprise - build 7601 SP 1 VM: VMware® Workstation 12 Player 12.1.1 build-3770994 (free) Guest: Fedora release 23

I naively failed to install open-vm-tools-desktop. I say naively because I had no idea such a thing existed, nor do I understand why instructions to install open-vm-tools do not (or at least where I read them, do not) include mentions of this package.

Installing open-vm-tools on its own appears to be nearly useless - the desktop package makes the copy and paste function - probably the single most important function of VMTools - work.

So, there you go. Install open-vm-tools-desktop, and copy-paste should work

HTML table sort

Here is another library.

Changes required are -

  1. Add sorttable js

  2. Add class name sortable to table.

Click the table headers to sort the table accordingly:

_x000D_
_x000D_
<script src="https://www.kryogenix.org/code/browser/sorttable/sorttable.js"></script>

<table class="sortable">
  <tr>
    <th>Name</th>
    <th>Address</th>
    <th>Sales Person</th>
  </tr>

  <tr class="item">
    <td>user:0001</td>
    <td>UK</td>
    <td>Melissa</td>
  </tr>
  <tr class="item">
    <td>user:0002</td>
    <td>France</td>
    <td>Justin</td>
  </tr>
  <tr class="item">
    <td>user:0003</td>
    <td>San Francisco</td>
    <td>Judy</td>
  </tr>
  <tr class="item">
    <td>user:0004</td>
    <td>Canada</td>
    <td>Skipper</td>
  </tr>
  <tr class="item">
    <td>user:0005</td>
    <td>Christchurch</td>
    <td>Alex</td>
  </tr>

</table>
_x000D_
_x000D_
_x000D_

Redirecting new tab on button click.(Response.Redirect) in asp.net C#

Wouldn't you be better off with

<asp:HyperLink ID="HyperLink1" runat="server" 
            NavigateUrl="CMS_1.aspx" 
            Target="_blank">
    Click here
</asp:HyperLink>

Because, to replicate your desired behavior on an asp:Button, you have to call window.open on the OnClientClick event of the button which looks a lot less cleaner than the above solution. Plus asp:HyperLink is there to handle scenarios like this.

If you want to replicate this using an asp:Button, do this.

<asp:Button ID="btn" runat="Server" 
        Text="SUBMIT"
        OnClientClick="javascript:return openRequestedPopup();"/>

JavaScript function.

var windowObjectReference;

function openRequestedPopup() {
    windowObjectReference = window.open("CMS_1.aspx",
              "DescriptiveWindowName",
              "menubar=yes,location=yes,resizable=yes,scrollbars=yes,status=yes");
}

milliseconds to days

public static final long SECOND_IN_MILLIS = 1000;
public static final long MINUTE_IN_MILLIS = SECOND_IN_MILLIS * 60;
public static final long HOUR_IN_MILLIS = MINUTE_IN_MILLIS * 60;
public static final long DAY_IN_MILLIS = HOUR_IN_MILLIS * 24;
public static final long WEEK_IN_MILLIS = DAY_IN_MILLIS * 7;

You could cast int but I would recommend using long.

How to find controls in a repeater header or footer

private T GetHeaderControl<T>(Repeater rp, string id) where T : Control
{
    T returnValue = null;
    if (rp != null && !String.IsNullOrWhiteSpace(id))
    {
        returnValue = rp.Controls.Cast<RepeaterItem>().Where(i => i.ItemType == ListItemType.Header).Select(h => h.FindControl(id) as T).Where(c => c != null).FirstOrDefault();
    }
    return returnValue;
}

Finds and casts the control. (Based on Piyey's VB answer)

What is "pom" packaging in maven?

POM(Project Object Model) is nothing but the automation script for building the project,we can write the automation script in XML, the building script files are named diffrenetly in different Automation tools

like we call build.xml in ANT,pom.xml in MAVEN

MAVEN can packages jars,wars, ears and POM which new thing to all of us

if you want check WHAT IS POM.XML

In c++ what does a tilde "~" before a function name signify?

This is a destructor. It's called when the object is destroyed (out of life scope or deleted).

To be clear, you have to use ~NameOfTheClass like for the constructor, other names are invalid.

Center a column using Twitter Bootstrap 3

Because I never have the need to center only a single .col- within a .row, I set the following class on the wrapping .row of my target columns.

.col-center > [class*="col-"] {
    float: none;
    margin-left: auto;
    margin-right: auto;
}

Example

<div class="full-container">
    <div class="row col-center">
        <div class="col-xs-11">
            Foo
        </div>
        <div class="col-xs-11">
            Bar
        </div>
    </div>
</div>

php execute a background process

Can you arrange to fork off a separate process, and then run your copy in the background? It's been a while since I did any PHP, but the function pcntl-fork looks promising.

Why is document.body null in my javascript?

The body hasn't been defined at this point yet. In general, you want to create all elements before you execute javascript that uses these elements. In this case you have some javascript in the head section that uses body. Not cool.

You want to wrap this code in a window.onload handler or place it after the <body> tag (as mentioned by e-bacho 2.0).

<head>
    <title>Javascript Tests</title>

    <script type="text/javascript">
      window.onload = function() {
        var mySpan = document.createElement("span");
        mySpan.innerHTML = "This is my span!";

        mySpan.style.color = "red";
        document.body.appendChild(mySpan);

        alert("Why does the span change after this alert? Not before?");
      }

    </script>
</head>

See demo.

ORA-00907: missing right parenthesis

ORA-00907: missing right parenthesis

This is one of several generic error messages which indicate our code contains one or more syntax errors. Sometimes it may mean we literally have omitted a right bracket; that's easy enough to verify if we're using an editor which has a match bracket capability (most text editors aimed at coders do). But often it means the compiler has come across a keyword out of context. Or perhaps it's a misspelled word, a space instead of an underscore or a missing comma.

Unfortunately the possible reasons why our code won't compile is virtually infinite and the compiler just isn't clever enough to distinguish them. So it hurls a generic, slightly cryptic, message like ORA-00907: missing right parenthesis and leaves it to us to spot the actual bloomer.

The posted script has several syntax errors. First I will discuss the error which triggers that ORA-0097 but you'll need to fix them all.

Foreign key constraints can be declared in line with the referencing column or at the table level after all the columns have been declared. These have different syntaxes; your scripts mix the two and that's why you get the ORA-00907.

In-line declaration doesn't have a comma and doesn't include the referencing column name.

CREATE TABLE historys_T    (
    history_record    VARCHAR2 (8),
    customer_id       VARCHAR2 (8) 
          CONSTRAINT historys_T_FK FOREIGN KEY REFERENCES T_customers ON DELETE CASCADE,
    order_id           VARCHAR2 (10) NOT NULL,
          CONSTRAINT fk_order_id_orders REFERENCES orders ON DELETE CASCADE)

Table level constraints are a separate component, and so do have a comma and do mention the referencing column.

CREATE TABLE historys_T    (
    history_record    VARCHAR2 (8),
    customer_id       VARCHAR2 (8),    
    order_id           VARCHAR2 (10) NOT NULL,
    CONSTRAINT historys_T_FK FOREIGN KEY (customer_id) REFERENCES T_customers ON DELETE CASCADE,   
   CONSTRAINT fk_order_id_orders FOREIGN KEY (order_id) REFERENCES orders ON DELETE CASCADE)

Here is a list of other syntax errors:

  1. The referenced table (and the referenced primary key or unique constraint) must already exist before we can create a foreign key against them. So you cannot create a foreign key for HISTORYS_T before you have created the referenced ORDERS table.
  2. You have misspelled the names of the referenced tables in some of the foreign key clauses (LIBRARY_T and FORMAT_T).
  3. You need to provide an expression in the DEFAULT clause. For DATE columns that is usually the current date, DATE DEFAULT sysdate.

Looking at our own code with a cool eye is a skill we all need to gain to be successful as developers. It really helps to be familiar with Oracle's documentation. A side-by-side comparison of your code and the examples in the SQL Reference would have helped you resolved these syntax errors in considerably less than two days. Find it here (11g) and here (12c).

As well as syntax errors, your scripts contain design mistakes. These are not failures, but bad practice which should not become habits.

  1. You have not named most of your constraints. Oracle will give them a default name but it will be a horrible one, and makes the data dictionary harder to understand. Explicitly naming every constraint helps us navigate the physical database. It also leads to more comprehensible error messages when our SQL trips a constraint violation.
  2. Name your constraints consistently. HISTORY_T has constraints called historys_T_FK and fk_order_id_orders, neither of which is helpful. A useful convention is <child_table>_<parent_table>_fk. So history_customer_fk and history_order_fk respectively.
  3. It can be useful to create the constraints with separate statements. Creating tables then primary keys then foreign keys will avoid the problems with dependency ordering identified above.
  4. You are trying to create cyclic foreign keys between LIBRARY_T and FORMATS. You could do this by creating the constraints in separate statement but don't: you will have problems when inserting rows and even worse problems with deletions. You should reconsider your data model and find a way to model the relationship between the two tables so that one is the parent and the other the child. Or perhaps you need a different kind of relationship, such as an intersection table.
  5. Avoid blank lines in your scripts. Some tools will handle them but some will not. We can configure SQL*Plus to handle them but it's better to avoid the need.
  6. The naming convention of LIBRARY_T is ugly. Try to find a more expressive name which doesn't require a needless suffix to avoid a keyword clash.
  7. T_CUSTOMERS is even uglier, being both inconsistent with your other tables and completely unnecessary, as customers is not a keyword.

Naming things is hard. You wouldn't believe the wrangles I've had about table names over the years. The most important thing is consistency. If I look at a data dictionary and see tables called T_CUSTOMERS and LIBRARY_T my first response would be confusion. Why are these tables named with different conventions? What conceptual difference does this express? So, please, decide on a naming convention and stick to. Make your table names either all singular or all plural. Avoid prefixes and suffixes as much as possible; we already know it's a table, we don't need a T_ or a _TAB.

jQuery check if <input> exists and has a value

The input won't have a value if it doesn't exist. Try this...

if($('.input1').val())

Your branch is ahead of 'origin/master' by 3 commits

$ git fetch

  - remote: Enumerating objects: 3, done.
  - remote: Counting objects: 100% (3/3), done.
  - remote: Compressing objects: 100% (3/3), done.
  - remote: Total 3 (delta 0), reused 0 (delta 0), pack-reused 0


$ git pull 

   - Already up to date!
   - Merge made by the 'recursive' strategy.

finally:

$ git push origin

How can I Remove .DS_Store files from a Git repository?

I'm a bit late to the party, but I have a good answer. To remove the .DS_Store files, use the following commands from a terminal window, but be very careful deleting files with 'find'. Using a specific name with the -name option is one of the safer ways to use it:

cd directory/above/affected/workareas
find . -name .DS_Store -delete

You can leave off the "-delete" if you want to simply list them before and after. That will reassure you that they're gone.

With regard to the ~/.gitignore_global advice: be careful here. You want to place that nice file into .gitignore within the top level of each workarea and commit it, so that anyone who clones your repo will gain the benefit of its use.

How to inflate one view with a layout

It's helpful to add to this, even though it's an old post, that if the child view that is being inflated from xml is to be added to a viewgroup layout, you need to call inflate with a clue of what type of viewgroup it is going to be added to. Like:

View child = getLayoutInflater().inflate(R.layout.child, item, false);

The inflate method is quite overloaded and describes this part of the usage in the docs. I had a problem where a single view inflated from xml wasn't aligning in the parent properly until I made this type of change.

apt-get for Cygwin?

Update: you can read the more complex answer, which contains more methods and information.

There exists a couple of scripts, which can be used as simple package managers. But as far as I know, none of them allows you to upgrade packages, because it’s not an easy task on Windows since there is not possible to overwrite files in use. So you have to close all Cygwin instances first and then you can use Cygwin’s native setup.exe (which itself does the upgrade via “replace after reboot” method, when files are in use).


apt-cyg

The best one for me. Simply because it’s one of the most recent. It works correctly for both platforms - x86 and x86_64. There exists a lot of forks with some additional features. For example the kou1okada fork is one of improved versions.


Cygwin’s setup.exe

It has also command line mode. Moreover it allows you to upgrade all installed packages at once.

setup.exe-x86_64.exe -q --packages=bash,vim

Example use:

setup.exe-x86_64.exe -q --packages="bash,vim"

You can create an alias for easier use, for example:

alias cyg-get="/cygdrive/d/path/to/cygwin/setup-x86_64.exe -q -P"

Then you can for example install the Vim package with:

cyg-get vim

How to determine the content size of a UIWebView?

This's weird!

I tested the solutions both sizeThatFits: and [webView stringByEvaluatingJavaScriptFromString:@"document.body.scrollHeight"] are NOT working for me.

However, I found an interesting easy way to get the right height of webpage content. Currently, I used it in my delegate method scrollViewDidScroll:.

CGFloat contentHeight = scrollView.contentSize.height - CGRectGetHeight(scrollView.frame);

Verified in iOS 9.3 Simulator/Device, good luck!

EDIT:

Background: The html content is calculated by my string variable and HTTP content template, loaded by method loadHTMLString:baseURL:, no registered JS scripts there.

add id to dynamically created <div>

You can add the id="MyID123" at the start of the cartHTML text appends.

The first line would therefore be:

var cartHTML = '<div id="MyID123" class="soft_add_wrapper" onmouseover="setTimer();">';

-OR-

If you want the ID to be in a variable, then something like this:

    var MyIDvariable = "MyID123";
    var cartHTML = '<div id="'+MyIDvariable+'" class="soft_add_wrapper" onmouseover="setTimer();">';
/* ... the rest of your code ... */

Expected block end YAML error

The line starting ALREADYEXISTS uses as the closing quote, it should be using '. The open quote on the next line (where the error is reported) is seen as the closing quote, and this mix up is causing the error.

403 Access Denied on Tomcat 8 Manager App without prompting for user/password

The solution that worked for me is edit context.xml files in both $CATALINA_HOME/webapps/manager/META-INF and $CATALINA_HOME/webapps/host-manager/META-INF where my ip is 123.123.123.123.

<Context antiResourceLocking="false" privileged="true" >
  <Valve className="org.apache.catalina.valves.RemoteAddrValve"
         allow="127\.\d+\.\d+\.\d+|::1|0:0:0:0:0:0:0:1|123.123.123.123" />
</Context>

I installed Tomcat 8.5 on Ubuntu and edited $CATALINA_HOME/conf/tomcat-users.xml:

<role rolename="admin-gui"/>
<role rolename="manager-gui"/>
<user username="myuser" password="mypass" roles="admin-gui,manager-gui"/>

However, I still couldn't access both Tomcat Web Application Manager (localhost:8080/manager/html) and Tomcat Virtual Host Manager (localhost:8080/host-manager/html) until I edited context.xml files.

How to get client IP address using jQuery

function GetUserIP(){
  var ret_ip;
  $.ajaxSetup({async: false});
  $.get('http://jsonip.com/', function(r){ 
    ret_ip = r.ip; 
  });
  return ret_ip;
}

If you want to use the IP and assign it to a variable, Try this. Just call GetUserIP()

Excel function to make SQL-like queries on worksheet data?

One quick way to do this is to create a column with a formula that evaluates to true for the rows you care about and then filter for the value TRUE in that column.

AngularJS : The correct way of binding to a service properties

Building on the examples above I thought I'd throw in a way of transparently binding a controller variable to a service variable.

In the example below changes to the Controller $scope.count variable will automatically be reflected in the Service count variable.

In production we're actually using the this binding to update an id on a service which then asynchronously fetches data and updates its service vars. Further binding that means that controllers automagically get updated when the service updates itself.

The code below can be seen working at http://jsfiddle.net/xuUHS/163/

View:

<div ng-controller="ServiceCtrl">
    <p> This is my countService variable : {{count}}</p>
    <input type="number" ng-model="count">
    <p> This is my updated after click variable : {{countS}}</p>

    <button ng-click="clickC()" >Controller ++ </button>
    <button ng-click="chkC()" >Check Controller Count</button>
    </br>

    <button ng-click="clickS()" >Service ++ </button>
    <button ng-click="chkS()" >Check Service Count</button>
</div>

Service/Controller:

var app = angular.module('myApp', []);

app.service('testService', function(){
    var count = 10;

    function incrementCount() {
      count++;
      return count;
    };

    function getCount() { return count; }

    return {
        get count() { return count },
        set count(val) {
            count = val;
        },
        getCount: getCount,
        incrementCount: incrementCount
    }

});

function ServiceCtrl($scope, testService)
{

    Object.defineProperty($scope, 'count', {
        get: function() { return testService.count; },
        set: function(val) { testService.count = val; },
    });

    $scope.clickC = function () {
       $scope.count++;
    };
    $scope.chkC = function () {
        alert($scope.count);
    };

    $scope.clickS = function () {
       ++testService.count;
    };
    $scope.chkS = function () {
        alert(testService.count);
    };

}

The request failed or the service did not respond in a timely fashion?

After chasing this issue for some hours, we found an log in the SQL Server Agent logs stating the following:

This installation of SQL Server Agent is disabled. The edition of SQL server that installed this service does not support SQL server agent.

We were using SQL Server Express. After some Googling it appears SQL Server Express does not support SQL Server Agent.

I didn't find a direct piece of Microsoft communications stating that SQL Express doesn't support SQL Server Agent, however this sentiment seems to be echoed across many forums.

Java rounding up to an int using Math.ceil

Nobody has mentioned the most intuitive:

int x = (int) Math.round(Math.ceil((double) 157 / 32));

This solution fixes the double division imprecision.

SQL: Select columns with NULL values only

You'll have to loop over the set of columns and check each one. You should be able to get a list of all columns with a DESCRIBE table command.

Pseudo-code:


foreach $column ($cols) {
   query("SELECT count(*) FROM table WHERE $column IS NOT NULL")
   if($result is zero)  {
      # $column contains only null values"
      push @onlyNullColumns, $column;
   } else {
      # $column contains non-null values
   }
}
return @onlyNullColumns;

I know this seems a little counterintuitive but SQL does not provide a native method of selecting columns, only rows.

Font Awesome not working, icons showing as squares

Open your font-awesome.css theres code like :

@font-face {
  font-family: 'FontAwesome';
  src: url('../fonts/fontawesome-webfont.eot?v=4.5.0');
  src: url('../fonts/fontawesome-webfont.eot?#iefix&v=4.5.0') format('embedded-opentype'), url('../fonts/fontawesome-webfont.woff2?v=4.5.0') format('woff2'), url('../fonts/fontawesome-webfont.woff?v=4.5.0') format('woff'), url('../fonts/fontawesome-webfont.ttf?v=4.5.0') format('truetype'), url('../fonts/fontawesome-webfont.svg?v=4.5.0#fontawesomeregular') format('svg');
  font-weight: normal;
  font-style: normal;
}

you must have folder like :

font awesome -> css
             -> fonts

or the easiest way :

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.4.0/css/font-awesome.min.css">

Could not create the Java virtual machine

Make sure the physical available memory is more then VM defined min/max memory.

Scraping: SSL: CERTIFICATE_VERIFY_FAILED error for http://en.wikipedia.org

i didn't solve the problem, sadly. but managed to make to codes work (almost all of my codes have this probelm btw) the local issuer certificate problem happens under python3.7 so i changed back to python2.7 QAQ and all that needed to change including "from urllib2 import urlopen" instead of "from urllib.request import urlopen" so sad...

Parsing XML in Python using ElementTree example

So I have ElementTree 1.2.6 on my box now, and ran the following code against the XML chunk you posted:

import elementtree.ElementTree as ET

tree = ET.parse("test.xml")
doc = tree.getroot()
thingy = doc.find('timeSeries')

print thingy.attrib

and got the following back:

{'name': 'NWIS Time Series Instantaneous Values'}

It appears to have found the timeSeries element without needing to use numerical indices.

What would be useful now is knowing what you mean when you say "it doesn't work." Since it works for me given the same input, it is unlikely that ElementTree is broken in some obvious way. Update your question with any error messages, backtraces, or anything you can provide to help us help you.

Why does overflow:hidden not work in a <td>?

I'm not familiar with the specific issue, but you could stick a div, etc inside the td and set overflow on that.

MySQL, Check if a column exists in a table with SQL

Just to help anyone who is looking for a concrete example of what @Mchl was describing, try something like

 SELECT * FROM information_schema.COLUMNS 
 WHERE TABLE_SCHEMA = 'my_schema' AND TABLE_NAME = 'my_table' 
 AND COLUMN_NAME = 'my_column'`

If it returns false (zero results) then you know the column doesn't exist.

SQL Server procedure declare a list

If you want input comma separated string as input & apply in in query in that then you can make Function like:

create FUNCTION [dbo].[Split](@String varchar(MAX), @Delimiter char(1))       
    returns @temptable TABLE (items varchar(MAX))       
    as       
    begin      
        declare @idx int       
        declare @slice varchar(8000)       

        select @idx = 1       
            if len(@String)<1 or @String is null  return       

        while @idx!= 0       
        begin       
            set @idx = charindex(@Delimiter,@String)       
            if @idx!=0       
                set @slice = left(@String,@idx - 1)       
            else       
                set @slice = @String       

            if(len(@slice)>0)  
                insert into @temptable(Items) values(@slice)       

            set @String = right(@String,len(@String) - @idx)       
            if len(@String) = 0 break       
        end   
    return 
    end;

You can use it like :

Declare @Values VARCHAR(MAX);

set @Values ='1,2,5,7,10';
Select * from DBTable
    Where id  in (select items from [dbo].[Split] (@Values, ',') )

Alternatively if you don't have comma-separated string as input, You can try Table variable OR TableType Or Temp table like: INSERT using LIST into Stored Procedure

How can I maintain fragment state when added to the back stack?

My problem was similar but I overcame me without keeping the fragment alive. Suppose you have an activity that has 2 fragments - F1 and F2. F1 is started initially and lets say in contains some user info and then upon some condition F2 pops on asking user to fill in additional attribute - their phone number. Next, you want that phone number to pop back to F1 and complete signup but you realize all previous user info is lost and you don't have their previous data. The fragment is recreated from scratch and even if you saved this information in onSaveInstanceState the bundle comes back null in onActivityCreated.

Solution: Save required information as an instance variable in calling activity. Then pass that instance variable into your fragment.

@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);

    Bundle args = getArguments();

    // this will be null the first time F1 is created. 
    // it will be populated once you replace fragment and provide bundle data
    if (args != null) {
        if (args.get("your_info") != null) {
            // do what you want with restored information
        }
    }
}

So following on with my example: before I display F2 I save user data in the instance variable using a callback. Then I start F2, user fills in phone number and presses save. I use another callback in activity, collect this information and replace my fragment F1, this time it has bundle data that I can use.

@Override
public void onPhoneAdded(String phone) {
        //replace fragment
        F1 f1 = new F1 ();
        Bundle args = new Bundle();
        yourInfo.setPhone(phone);
        args.putSerializable("you_info", yourInfo);
        f1.setArguments(args);

        getFragmentManager().beginTransaction()
                .replace(R.id.fragmentContainer, f1).addToBackStack(null).commit();

    }
}

More information about callbacks can be found here: https://developer.android.com/training/basics/fragments/communicating.html

Adding delay between execution of two following lines

You can use gcd to do this without having to create another method

double delayInSeconds = 2.0;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
  NSLog(@"Do some work");
});

You should still ask yourself "do I really need to add a delay" as it can often complicate code and cause race conditions

How to implement linear interpolation?

I thought up a rather elegant solution (IMHO), so I can't resist posting it:

from bisect import bisect_left

class Interpolate(object):
    def __init__(self, x_list, y_list):
        if any(y - x <= 0 for x, y in zip(x_list, x_list[1:])):
            raise ValueError("x_list must be in strictly ascending order!")
        x_list = self.x_list = map(float, x_list)
        y_list = self.y_list = map(float, y_list)
        intervals = zip(x_list, x_list[1:], y_list, y_list[1:])
        self.slopes = [(y2 - y1)/(x2 - x1) for x1, x2, y1, y2 in intervals]

    def __getitem__(self, x):
        i = bisect_left(self.x_list, x) - 1
        return self.y_list[i] + self.slopes[i] * (x - self.x_list[i])

I map to float so that integer division (python <= 2.7) won't kick in and ruin things if x1, x2, y1 and y2 are all integers for some iterval.

In __getitem__ I'm taking advantage of the fact that self.x_list is sorted in ascending order by using bisect_left to (very) quickly find the index of the largest element smaller than x in self.x_list.

Use the class like this:

i = Interpolate([1, 2.5, 3.4, 5.8, 6], [2, 4, 5.8, 4.3, 4])
# Get the interpolated value at x = 4:
y = i[4]

I've not dealt with the border conditions at all here, for simplicity. As it is, i[x] for x < 1 will work as if the line from (2.5, 4) to (1, 2) had been extended to minus infinity, while i[x] for x == 1 or x > 6 will raise an IndexError. Better would be to raise an IndexError in all cases, but this is left as an exercise for the reader. :)

opening html from google drive

Steps:

  1. Upload html file to the google drive and share it as "Public on the web" after uploading just make sure that the content of your html is not modified in the drive.
  2. Right click on the shared file and click on 'Get link' and save it to notepad it will look something like 'https://drive.google.com/open?id=0B55nkHvMDw18T3VaYjY3NEE4SEE'
  3. Take the code (about 28 character alphanumeric) after '=' sign from the above link and paste it after 'https://googledrive.com/host/' now 'https://googledrive.com/host/0B55nkHvMDw18T3VaYjY3NEE4SEE' is your actual sharable url link, open the html file from address bar of the browser using this url.

Generate a random number in a certain range in MATLAB

You can also use:

round(mod(rand.*max,max-1))+min

Get clicked element using jQuery on event?

The conventional way of handling this doesn't play well with ES6. You can do this instead:

$('.delete').on('click', event => {
  const clickedElement = $(event.target);

  this.delete(clickedElement.data('id'));
});

Note that the event target will be the clicked element, which may not be the element you want (it could be a child that received the event). To get the actual element:

$('.delete').on('click', event => {
  const clickedElement = $(event.target);
  const targetElement = clickedElement.closest('.delete');

  this.delete(targetElement.data('id'));
});

How can I convert a date to GMT?

You can simply use the toUTCString (or toISOString) methods of the date object.

Example:

new Date("Fri Jan 20 2012 11:51:36 GMT-0500").toUTCString()

// Output:  "Fri, 20 Jan 2012 16:51:36 GMT"

If you prefer better control of the output format, consider using a library such as date-fns or moment.js.

Also, in your question, you've actually converted the time incorrectly. When an offset is shown in a timestamp string, it means that the date and time values in the string have already been adjusted from UTC by that value. To convert back to UTC, invert the sign before applying the offset.

11:51:36 -0300  ==  14:51:36Z

no module named urllib.parse (How should I install it?)

The problem was because I had a lower version of Django (1.4.10), so Django Rest Framework need at least Django 1.4.11 or bigger. Thanks for their answers guys!

Here the link for the requirements of Django Rest: http://www.django-rest-framework.org/

How to pass credentials to the Send-MailMessage command for sending emails

And here is a simple Send-MailMessage example with username/password for anyone looking for just that

$secpasswd = ConvertTo-SecureString "PlainTextPassword" -AsPlainText -Force
$cred = New-Object System.Management.Automation.PSCredential ("username", $secpasswd)
Send-MailMessage -SmtpServer mysmptp -Credential $cred -UseSsl -From '[email protected]' -To '[email protected]' -Subject 'TEST'

How to convert JSONObjects to JSONArray?

Even shorter and with json-functions:

JSONObject songsObject = json.getJSONObject("songs");
JSONArray songsArray = songsObject.toJSONArray(songsObject.names());

SQL select only rows with max value on a column

You can make the select without a join when you combine the rev and id into one maxRevId value for MAX() and then split it back to original values:

SELECT maxRevId & ((1 << 32) - 1) as id, maxRevId >> 32 AS rev
FROM (SELECT MAX(((rev << 32) | id)) AS maxRevId
      FROM YourTable
      GROUP BY id) x;

This is especially fast when there is a complex join instead of a single table. With the traditional approaches the complex join would be done twice.

The above combination is simple with bit functions when rev and id are INT UNSIGNED (32 bit) and combined value fits to BIGINT UNSIGNED (64 bit). When the id & rev are larger than 32-bit values or made of multiple columns, you need combine the value into e.g. a binary value with suitable padding for MAX().

How to design RESTful search/filtering?

The best way to implement a RESTful search is to consider the search itself to be a resource. Then you can use the POST verb because you are creating a search. You do not have to literally create something in a database in order to use a POST.

For example:

Accept: application/json
Content-Type: application/json
POST http://example.com/people/searches
{
  "terms": {
    "ssn": "123456789"
  },
  "order": { ... },
  ...
}

You are creating a search from the user's standpoint. The implementation details of this are irrelevant. Some RESTful APIs may not even need persistence. That is an implementation detail.

Swift 3: Display Image from URL

You could also use Alamofire\AlmofireImage for that task: https://github.com/Alamofire/AlamofireImage

The code should look something like that (Based on the first example on link above):

import AlamofireImage

Alamofire.request("http://i.imgur.com/w5rkSIj.jpg").responseImage { response in
    if let catPicture = response.result.value {
        print("image downloaded: \(image)")
    }
}

While it is neat yet safe, you should consider if that worth the Pod overhead. If you are going to use more images and would like to add also filter and transiations I would consider using AlamofireImage

How often should Oracle database statistics be run?

Since Oracle 11g statistics are gathered automatically by default.

Two Scheduler windows are predefined upon installation of Oracle Database:

  • WEEKNIGHT_WINDOW starts at 10 p.m. and ends at 6 a.m. every Monday through Friday.
  • WEEKEND_WINDOW covers whole days Saturday and Sunday.

When statistics were last gathered?

SELECT owner, table_name, last_analyzed FROM all_tables ORDER BY last_analyzed DESC NULLS LAST; --Tables.
SELECT owner, index_name, last_analyzed FROM all_indexes ORDER BY last_analyzed DESC NULLS LAST; -- Indexes.

Status of automated statistics gathering?

SELECT * FROM dba_autotask_client WHERE client_name = 'auto optimizer stats collection';

Windows Groups?

SELECT window_group_name, window_name FROM dba_scheduler_wingroup_members;

Window Schedules?

SELECT window_name, start_time, duration FROM dba_autotask_schedule;

Manually gather Database Statistics in this Schema:

EXEC dbms_stats.gather_schema_stats(ownname=>NULL, cascade=>TRUE); -- cascade=>TRUE means include Table Indexes too.

Manually gather Database Statistics in all Schemas!

-- Probably need to CONNECT / AS SYSDBA
EXEC dbms_stats.gather_database_stats;

Assign keyboard shortcut to run procedure

The problem that I had with the above is that I wanted to associate a short cut key with a macro in an xlam which has no visible interface. I found that the folllowing worked

To associate a short cut key with a macro

In Excel (not VBA) on the Developer Tab click Macros - no macros will be shown Type the name of the Sub The Options button should then be enabled Click it Ctrl will be the default Hold down Shift and press the letter you want eg Shift and A will associate Ctrl-Shift-A with the Sub

Best Java obfuscator?

First, you really need to keep in mind that it's never impossible to reverse-engineer something. Everything is hackable. A smart developer using a smart IDE can already get far enough.

Well, you can find here a list. ProGuard is pretty good. I've used it myself, but only to "minify" Java code.

Drop rows with all zeros in pandas data frame

I think this solution is the shortest :

df= df[df['ColName'] != 0]

Ruby send JSON request

uri = URI('https://myapp.com/api/v1/resource')
req = Net::HTTP::Post.new(uri, 'Content-Type' => 'application/json')
req.body = {param1: 'some value', param2: 'some other value'}.to_json
res = Net::HTTP.start(uri.hostname, uri.port) do |http|
  http.request(req)
end

What does the Ellipsis object do?

In typer ... is used to create required parameters: The Argument class expects a default value, and if you pass the ... it will complain if the user does not pass the particular argument.

You could use None for the same if Ellipsis was not there, but this would remove the opportunity to express that None is the default value, in case that made any sense in your program.

How to round a Double to the nearest Int in swift?

**In Swift**

var a = 14.123456789
var b = 14.123456789
var c = 14.123456789
var d = 14.123456789
var e = 14.123456789
var f = 14.123456789

a.rounded(.up)                      //15
b.rounded(.down)                    //14
c.rounded(.awayFromZero)            //15
d.rounded(.towardZero)              //14
e.rounded(.toNearestOrAwayFromZero) //14
f.rounded(.toNearestOrEven)         //14

How to take character input in java

you can use a Scanner to read from input :

Scanner scanner = new Scanner(System.in); 
char c = scanner.next().charAt(0); //charAt() method returns the character at the specified index in a string. The index of the first character is 0, the second character is 1, and so on.

Resize image in PHP

I would suggest an easy way:

function resize($file, $width, $height) {
    switch(pathinfo($file)['extension']) {
        case "png": return imagepng(imagescale(imagecreatefrompng($file), $width, $height), $file);
        case "gif": return imagegif(imagescale(imagecreatefromgif($file), $width, $height), $file);
        default : return imagejpeg(imagescale(imagecreatefromjpeg($file), $width, $height), $file);
    }
}

How to replace space with comma using sed?

I just confirmed that:

cat file.txt | sed "s/\s/,/g"

successfully replaces spaces with commas in Cygwin terminals (mintty 2.9.0). None of the other samples worked for me.

How to convert Calendar to java.sql.Date in Java?

I found this code works:

SimpleDateFormat sdf = new SimpleDateFormat("yyyy MMM dd HH:mm:ss");    
Calendar calendar = new GregorianCalendar(2013,0,31);
System.out.println(sdf.format(calendar.getTime()));  

you can find the rest in this tutorial:
http://www.mkyong.com/java/java-date-and-calendar-examples/

Remove Elements from a HashSet while Iterating

You can manually iterate over the elements of the set:

Iterator<Integer> iterator = set.iterator();
while (iterator.hasNext()) {
    Integer element = iterator.next();
    if (element % 2 == 0) {
        iterator.remove();
    }
}

You will often see this pattern using a for loop rather than a while loop:

for (Iterator<Integer> i = set.iterator(); i.hasNext();) {
    Integer element = i.next();
    if (element % 2 == 0) {
        i.remove();
    }
}

As people have pointed out, using a for loop is preferred because it keeps the iterator variable (i in this case) confined to a smaller scope.

Generating a unique machine id

I had an additional constraint, I was using .net express so I couldn't use the standard hardware query mechanism. So I decided to use power shell to do the query. The full code looks like this:

Private Function GetUUID() As String
    Dim GetDiskUUID As String = "get-wmiobject Win32_ComputerSystemProduct  | Select-Object -ExpandProperty UUID"
    Dim X As String = ""
    Dim oProcess As New Process()
    Dim oStartInfo As New ProcessStartInfo("powershell.exe", GetDiskUUID)
    oStartInfo.UseShellExecute = False
    oStartInfo.RedirectStandardInput = True
    oStartInfo.RedirectStandardOutput = True
    oStartInfo.CreateNoWindow = True
    oProcess.StartInfo = oStartInfo
    oProcess.Start()
    oProcess.WaitForExit()
    X = oProcess.StandardOutput.ReadToEnd
    Return X.Trim()
End Function

$_POST Array from html form

You should get the array like in $_POST['id']. So you should be able to do this:

foreach ($_POST['id'] as $key => $value) {
    echo $value . "<br />";
}

Input names should be same:

<input name='id[]' type='checkbox' value='1'>
<input name='id[]' type='checkbox' value='2'>
...

What is the best way to left align and right align two div tags?

This solution has left aligned text and button on the far right.

If anyone is looking for a material design answer:

<div layout="column" layout-align="start start">
 <div layout="row" style="width:100%">
    <div flex="grow">Left Aligned text</div>
    <md-button aria-label="help" ng-click="showHelpDialog()">
      <md-icon md-svg-icon="help"></md-icon>
    </md-button>
 </div>
</div>  

Check Whether a User Exists

Script to Check whether Linux user exists or not

Script To check whether the user exists or not

#! /bin/bash
USER_NAME=bakul
cat /etc/passwd | grep ${USER_NAME} >/dev/null 2>&1
if [ $? -eq 0 ] ; then
    echo "User Exists"
else
    echo "User Not Found"
fi

How do you overcome the HTML form nesting limitation?

Alternatively you could assign the form actiob on the fly...might not be the best solution, but sure does relieve the server-side logic...

<form name="frm" method="post">  
    <input type="submit" value="One" onclick="javascript:this.form.action='1.htm'" />  
    <input type="submit" value="Two" onclick="javascript:this.form.action='2.htm'" />  
</form>

How to add an item to a drop down list in ASP.NET?

Which specific index? If you want 'Add New' to be first on the dropdownlist you can add it though the code like this:

<asp:DropDownList ID="DropDownList1" AppendDataBoundItems="true" runat="server">
     <asp:ListItem Text="Add New" Value="0" />
</asp:DropDownList>

If you want to add it at a different index, maybe the last then try:

ListItem lst = new ListItem ( "Add New" , "0" );

DropDownList1.Items.Insert( DropDownList1.Items.Count-1 ,lst);

How do I install PHP cURL on Linux Debian?

Whatever approach you take, make sure in the end that you have an updated version of curl and libcurl. You can do curl --version and see the versions.

Here's what I did to get the latest curl version installed in Ubuntu:

  1. sudo add-apt-repository "deb http://mirrors.kernel.org/ubuntu wily main"
  2. sudo apt-get update
  3. sudo apt-get install curl

Maximum size for a SQL Server Query? IN clause? Is there a Better Approach

Per batch, 65536 * Network Packet Size which is 4k so 256 MB

However, IN will stop way before that but it's not precise.

You end up with memory errors but I can't recall the exact error. A huge IN will be inefficient anyway.

Edit: Remus reminded me: the error is about "stack size"

Pandas: how to change all the values of a column?

As @DSM points out, you can do this more directly using the vectorised string methods:

df['Date'].str[-4:].astype(int)

Or using extract (assuming there is only one set of digits of length 4 somewhere in each string):

df['Date'].str.extract('(?P<year>\d{4})').astype(int)

An alternative slightly more flexible way, might be to use apply (or equivalently map) to do this:

df['Date'] = df['Date'].apply(lambda x: int(str(x)[-4:]))
             #  converts the last 4 characters of the string to an integer

The lambda function, is taking the input from the Date and converting it to a year.
You could (and perhaps should) write this more verbosely as:

def convert_to_year(date_in_some_format):
    date_as_string = str(date_in_some_format)  # cast to string
    year_as_string = date_in_some_format[-4:] # last four characters
    return int(year_as_string)

df['Date'] = df['Date'].apply(convert_to_year)

Perhaps 'Year' is a better name for this column...

C# equivalent of C++ vector, with contiguous memory?

You could use a List<T> and when T is a value type it will be allocated in contiguous memory which would not be the case if T is a reference type.

Example:

List<int> integers = new List<int>();
integers.Add(1);
integers.Add(4);
integers.Add(7);

int someElement = integers[1];

CSS endless rotation animation

Works in all modern browsers

.rotate{
 animation: loading 3s linear infinite;
 @keyframes loading {
  0% { 
    transform: rotate(0); 
  }
  100% { 
    transform: rotate(360deg);
  }
 }
}

What does this thread join code mean?

Simply put:
t1.join() returns after t1 is completed.
It doesn't do anything to thread t1, except wait for it to finish.
Naturally, code following t1.join() will be executed only after t1.join() returns.

Pass props in Link react-router

there is a way you can pass more than one parameter. You can pass "to" as object instead of string.

// your route setup
<Route path="/category/:catId" component={Category} / >

// your link creation
const newTo = { 
  pathname: "/category/595212758daa6810cbba4104", 
  param1: "Par1" 
};
// link to the "location"
// see (https://reacttraining.com/react-router/web/api/location)
<Link to={newTo}> </Link>

// In your Category Component, you can access the data like this
this.props.match.params.catId // this is 595212758daa6810cbba4104 
this.props.location.param1 // this is Par1

PHP json_encode json_decode UTF-8

  header('Content-Type: application/json; charset=utf-8');

sh: react-scripts: command not found after running npm start

you should not install react-scripts globally, for me this fixed the problem:

npm install --save react react-dom react-scripts

if this still dont work :

  1. update to latest npm version : npm install -g npm@latest
  2. delete node_modules directory
  3. reinstall all dependencies : npm install

Recommended way to save uploaded files in a servlet application

I post my final way of doing it based on the accepted answer:

@SuppressWarnings("serial")
@WebServlet("/")
@MultipartConfig
public final class DataCollectionServlet extends Controller {

    private static final String UPLOAD_LOCATION_PROPERTY_KEY="upload.location";
    private String uploadsDirName;

    @Override
    public void init() throws ServletException {
        super.init();
        uploadsDirName = property(UPLOAD_LOCATION_PROPERTY_KEY);
    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        // ...
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        Collection<Part> parts = req.getParts();
        for (Part part : parts) {
            File save = new File(uploadsDirName, getFilename(part) + "_"
                + System.currentTimeMillis());
            final String absolutePath = save.getAbsolutePath();
            log.debug(absolutePath);
            part.write(absolutePath);
            sc.getRequestDispatcher(DATA_COLLECTION_JSP).forward(req, resp);
        }
    }

    // helpers
    private static String getFilename(Part part) {
        // courtesy of BalusC : http://stackoverflow.com/a/2424824/281545
        for (String cd : part.getHeader("content-disposition").split(";")) {
            if (cd.trim().startsWith("filename")) {
                String filename = cd.substring(cd.indexOf('=') + 1).trim()
                        .replace("\"", "");
                return filename.substring(filename.lastIndexOf('/') + 1)
                        .substring(filename.lastIndexOf('\\') + 1); // MSIE fix.
            }
        }
        return null;
    }
}

where :

@SuppressWarnings("serial")
class Controller extends HttpServlet {

    static final String DATA_COLLECTION_JSP="/WEB-INF/jsp/data_collection.jsp";
    static ServletContext sc;
    Logger log;
    // private
    // "/WEB-INF/app.properties" also works...
    private static final String PROPERTIES_PATH = "WEB-INF/app.properties";
    private Properties properties;

    @Override
    public void init() throws ServletException {
        super.init();
        // synchronize !
        if (sc == null) sc = getServletContext();
        log = LoggerFactory.getLogger(this.getClass());
        try {
            loadProperties();
        } catch (IOException e) {
            throw new RuntimeException("Can't load properties file", e);
        }
    }

    private void loadProperties() throws IOException {
        try(InputStream is= sc.getResourceAsStream(PROPERTIES_PATH)) {
                if (is == null)
                    throw new RuntimeException("Can't locate properties file");
                properties = new Properties();
                properties.load(is);
        }
    }

    String property(final String key) {
        return properties.getProperty(key);
    }
}

and the /WEB-INF/app.properties :

upload.location=C:/_/

HTH and if you find a bug let me know

Easy way to test a URL for 404 in PHP?

addendum;tested those 3 methods considering performance.

The result, at least in my testing environment:

Curl wins

This test is done under the consideration that only the headers (noBody) is needed. Test yourself:

$url = "http://de.wikipedia.org/wiki/Pinocchio";

$start_time = microtime(TRUE);
$headers = get_headers($url);
echo $headers[0]."<br>";
$end_time = microtime(TRUE);
echo $end_time - $start_time."<br>";


$start_time = microtime(TRUE);
$response = file_get_contents($url);
echo $http_response_header[0]."<br>";
$end_time = microtime(TRUE);
echo $end_time - $start_time."<br>";

$start_time = microtime(TRUE);
$handle = curl_init($url);
curl_setopt($handle,  CURLOPT_RETURNTRANSFER, TRUE);
curl_setopt($handle, CURLOPT_NOBODY, 1); // and *only* get the header 
/* Get the HTML or whatever is linked in $url. */
$response = curl_exec($handle);
/* Check for 404 (file not found). */
$httpCode = curl_getinfo($handle, CURLINFO_HTTP_CODE);
// if($httpCode == 404) {
    // /* Handle 404 here. */
// }
echo $httpCode."<br>";
curl_close($handle);
$end_time = microtime(TRUE);
echo $end_time - $start_time."<br>";

Convert Time DataType into AM PM Format:

Use following syntax to convert a time to AM PM format.

Replace the field name with the value in following query.

select CONVERT(varchar(15),CAST('17:30:00.0000000' AS TIME),100)

Generate GUID in MySQL for existing Data?

MYsql

UPDATE tablename   SET columnName = UUID()

oracle

UPDATE tablename   SET columnName = SYS_GUID();

SQLSERVER

UPDATE tablename   SET columnName = NEWID();;

Error Code: 2013. Lost connection to MySQL server during query

Start the DB server with the comandline option net_read_timeout / wait_timeout and a suitable value (in seconds) - for example: --net_read_timeout=100.

For reference see here and here.

Load image from url

public class MainActivity extends Activity {

    Bitmap b;
    ImageView img;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        img = (ImageView)findViewById(R.id.imageView1);
        information info = new information();
        info.execute("");
    }

    public class information extends AsyncTask<String, String, String>
    {
        @Override
        protected String doInBackground(String... arg0) {

            try
            {
                URL url = new URL("http://10.119.120.10:80/img.jpg");
                InputStream is = new BufferedInputStream(url.openStream());
                b = BitmapFactory.decodeStream(is);

            } catch(Exception e){}
            return null;
        }

        @Override
        protected void onPostExecute(String result) {
            img.setImageBitmap(b);
        }
    }
}

:last-child not working as expected?

:last-child will not work if the element is not the VERY LAST element

In addition to Harry's answer, I think it's crucial to add/emphasize that :last-child will not work if the element is not the VERY LAST element in a container. For whatever reason it took me hours to realize that, and even though Harry's answer is very thorough I couldn't extract that information from "The last-child selector is used to select the last child element of a parent."

Suppose this is my selector: a:last-child {}

This works:

<div>
    <a></a>
    <a>This will be selected</a>
</div>

This doesn't:

<div>
    <a></a>
    <a>This will no longer be selected</a>
    <div>This is now the last child :'( </div>
</div>

It doesn't because the a element is not the last element inside its parent.

It may be obvious, but it was not for me...

Changing the URL in react-router v4 without using Redirect or Link

I'm using this to redirect with React Router v4:

this.props.history.push('/foo');

Hope it work for you ;)

How to access private data members outside the class without making "friend"s?

You can't. That member is private, it's not visible outside the class. That's the whole point of the public/protected/private modifiers.

(You could probably use dirty pointer tricks though, but my guess is that you'd enter undefined behavior territory pretty fast.)

Is there any way to wait for AJAX response and halt execution?

The simple answer is to turn off async. But that's the wrong thing to do. The correct answer is to re-think how you write the rest of your code.

Instead of writing this:

function functABC(){
    $.ajax({
        url: 'myPage.php',
        data: {id: id},
        success: function(data) {
            return data;
        }
    });
}

function foo () {
    var response = functABC();
    some_result = bar(response);
    // and other stuff and
    return some_result;
}

You should write it like this:

function functABC(callback){
    $.ajax({
        url: 'myPage.php',
        data: {id: id},
        success: callback
    });
}

function foo (callback) {
    functABC(function(data){
        var response = data;
        some_result = bar(response);
        // and other stuff and
        callback(some_result);
    })
}

That is, instead of returning result, pass in code of what needs to be done as callbacks. As I've shown, callbacks can be nested to as many levels as you have function calls.


A quick explanation of why I say it's wrong to turn off async:

Turning off async will freeze the browser while waiting for the ajax call. The user cannot click on anything, cannot scroll and in the worst case, if the user is low on memory, sometimes when the user drags the window off the screen and drags it in again he will see empty spaces because the browser is frozen and cannot redraw. For single threaded browsers like IE7 it's even worse: all websites freeze! Users who experience this may think you site is buggy. If you really don't want to do it asynchronously then just do your processing in the back end and refresh the whole page. It would at least feel not buggy.

Forcing anti-aliasing using css: Is this a myth?

I doubt there is anyway to force a browser to do anything. It would depend on the system configuration, the font used, browser settings, etc. It sounds like BS to me too.

As a note, always use relative sizes not PX.

What is the purpose of Android's <merge> tag in XML layouts?

Another reason to use merge is when using custom viewgroups in ListViews or GridViews. Instead of using the viewHolder pattern in a list adapter, you can use a custom view. The custom view would inflate an xml whose root is a merge tag. Code for adapter:

public class GridViewAdapter extends BaseAdapter {
     // ... typical Adapter class methods
     @Override
     public View getView(int position, View convertView, ViewGroup parent) {
        WallpaperView wallpaperView;
        if (convertView == null)
           wallpaperView = new WallpaperView(activity);
        else
            wallpaperView = (WallpaperView) convertView;

        wallpaperView.loadWallpaper(wallpapers.get(position), imageWidth);
        return wallpaperView;
    }
}

here is the custom viewgroup:

public class WallpaperView extends RelativeLayout {

    public WallpaperView(Context context) {
        super(context);
        init(context);
    }
    // ... typical constructors

    private void init(Context context) {
        View.inflate(context, R.layout.wallpaper_item, this);
        imageLoader = AppController.getInstance().getImageLoader();
        imagePlaceHolder = (ImageView) findViewById(R.id.imgLoader2);
        thumbnail = (NetworkImageView) findViewById(R.id.thumbnail2);
        thumbnail.setScaleType(ImageView.ScaleType.CENTER_CROP);
    }

    public void loadWallpaper(Wallpaper wallpaper, int imageWidth) {
        // ...some logic that sets the views
    }
}

and here is the XML:

<merge xmlns:android="http://schemas.android.com/apk/res/android">

    <ImageView
        android:id="@+id/imgLoader"
        android:layout_width="30dp"
        android:layout_height="30dp"
        android:layout_centerInParent="true"
        android:src="@drawable/ico_loader" />

    <com.android.volley.toolbox.NetworkImageView
        android:id="@+id/thumbnail"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</merge>

How do I run msbuild from the command line using Windows SDK 7.1?

Using the "Developer Command Prompt for Visual Studio 20XX" instead of "cmd" will set the path for msbuild automatically without having to add it to your environment variables.

How to send an HTTPS GET Request in C#

Simple Get Request using HttpClient Class

using System.Net.Http;

class Program
{
   static void Main(string[] args)
    {
        HttpClient httpClient = new HttpClient();
        var result = httpClient.GetAsync("https://www.google.com").Result;
    }

}

How to change the URI (URL) for a remote Git repository?

If your repository is private then

  1. Open Control Panel from the Start menu
  2. Select User Accounts
  3. Select "Manage your credentials" in the left hand menu
  4. Delete any credentials related to Git or GitHub

Reference

How to disable a button when an input is empty?

its simple let us assume you have made an state full class by extending Component which contains following

class DisableButton extends Components 
   {

      constructor()
       {
         super();
         // now set the initial state of button enable and disable to be false
          this.state = {isEnable: false }
       }

  // this function checks the length and make button to be enable by updating the state
     handleButtonEnable(event)
       {
         const value = this.target.value;
         if(value.length > 0 )
        {
          // set the state of isEnable to be true to make the button to be enable
          this.setState({isEnable : true})
        }


       }

      // in render you having button and input 
     render() 
       {
          return (
             <div>
                <input
                   placeholder={"ANY_PLACEHOLDER"}
                   onChange={this.handleChangePassword}

                  />

               <button 
               onClick ={this.someFunction}
               disabled = {this.state.isEnable} 
              /> 

             <div/>
            )

       }

   }

How to create an Explorer-like folder browser control?

Microsoft provides a walkthrough for creating a Windows Explorer style interface in C#.

There are also several examples on Code Project and other sites. Immediate examples are Explorer Tree, My Explorer, File Browser and Advanced File Explorer but there are others. Explorer Tree seems to look the best from the brief glance I took.

I used the search term windows explorer tree view C# in Google to find these links.

How to specify the download location with wget?

Make sure you have the URL correct for whatever you are downloading. First of all, URLs with characters like ? and such cannot be parsed and resolved. This will confuse the cmd line and accept any characters that aren't resolved into the source URL name as the file name you are downloading into.

For example:

wget "sourceforge.net/projects/ebosse/files/latest/download?source=typ_redirect"

will download into a file named, ?source=typ_redirect.

As you can see, knowing a thing or two about URLs helps to understand wget.

I am booting from a hirens disk and only had Linux 2.6.1 as a resource (import os is unavailable). The correct syntax that solved my problem downloading an ISO onto the physical hard drive was:

wget "(source url)" -O (directory where HD was mounted)/isofile.iso" 

One could figure the correct URL by finding at what point wget downloads into a file named index.html (the default file), and has the correct size/other attributes of the file you need shown by the following command:

wget "(source url)"

Once that URL and source file is correct and it is downloading into index.html, you can stop the download (ctrl + z) and change the output file by using:

-O "<specified download directory>/filename.extension"

after the source url.

In my case this results in downloading an ISO and storing it as a binary file under isofile.iso, which hopefully mounts.

How to create query parameters in Javascript?

I have improved the function of shog9`s to handle array values

function encodeQueryData(data) {
    const ret = [];
    for (let d in data) {
        if (typeof data[d] === 'object' || typeof data[d] === 'array') {
            for (let arrD in data[d]) {
                ret.push(`${encodeURIComponent(d)}[]=${encodeURIComponent(data[d][arrD])}`)
            }
        } else if (typeof data[d] === 'null' || typeof data[d] === 'undefined') {
            ret.push(encodeURIComponent(d))
        } else {
            ret.push(`${encodeURIComponent(d)}=${encodeURIComponent(data[d])}`)
        }

    }
    return ret.join('&');
}

Example

let data = {
  user: 'Mark'
  fruits: ['apple', 'banana']
}

encodeQueryData(data) // user=Mark&fruits[]=apple&fruits[]=banana

Check if a Python list item contains a string inside another string

I did a search, which requires you to input a certain value, then it will look for a value from the list which contains your input:

my_list = ['abc-123',
        'def-456',
        'ghi-789',
        'abc-456'
        ]

imp = raw_input('Search item: ')

for items in my_list:
    val = items
    if any(imp in val for items in my_list):
        print(items)

Try searching for 'abc'.

How do I interpret precision and scale of a number in a database?

Numeric precision refers to the maximum number of digits that are present in the number.

ie 1234567.89 has a precision of 9

Numeric scale refers to the maximum number of decimal places

ie 123456.789 has a scale of 3

Thus the maximum allowed value for decimal(5,2) is 999.99