Programs & Examples On #Sqlmetal

The SqlMetal command-line tool generates code and mapping for the LINQ to SQL component of the .NET Framework.

How to calculate 1st and 3rd quartiles?

If you want to use raw python rather than numpy or panda, you can use the python stats module to find the median of the upper and lower half of the list:

    >>> import statistics as stat
    >>> def quartile(data):
            data.sort()               
            half_list = int(len(data)//2)
            upper_quartile = stat.median(data[-half_list]
            lower_quartile = stat.median(data[:half_list])
            print("Lower Quartile: "+str(lower_quartile))
            print("Upper Quartile: "+str(upper_quartile))
            print("Interquartile Range: "+str(upper_quartile-lower_quartile)

    >>> quartile(df.time_diff)

Line 1: import the statistics module under the alias "stat"

Line 2: define the quartile function

Line 3: sort the data into ascending order

Line 4: get the length of half of the list

Line 5: get the median of the lower half of the list

Line 6: get the median of the upper half of the list

Line 7: print the lower quartile

Line 8: print the upper quartile

Line 9: print the interquartile range

Line 10: run the quartile function for the time_diff column of the DataFrame

Count number of columns in a table row

If the colspan or rowspan is all set to 1, counting the children tds will give the correct answer. However, if there are spans, we cannot count the number of columns exactly, even by the maximum number of tds of the rows. Consider the following example:

_x000D_
_x000D_
var mytable = document.getElementById('table')_x000D_
for (var i=0; i < mytable.rows.length; ++i) {_x000D_
 document.write(mytable.rows[i].cells.length + "<br>");_x000D_
}
_x000D_
table, th, td {_x000D_
  border: 1px solid black;_x000D_
  border-collapse: collapse;_x000D_
  padding: 3px;_x000D_
}
_x000D_
<table id="table">_x000D_
    <thead>_x000D_
        <tr>_x000D_
            <th colspan="2">Header</th>_x000D_
            <th rowspan="2">Hi</th>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <th>Month</th>_x000D_
            <th>Savings</th>_x000D_
        </tr>_x000D_
    </thead>_x000D_
    <tbody>_x000D_
        <tr>_x000D_
            <td colspan="2">hello</td>_x000D_
            <td>world</td>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <td>hello</td>_x000D_
            <td colspan="2">again</td>_x000D_
        </tr>_x000D_
    </tbody>_x000D_
</table>
_x000D_
_x000D_
_x000D_

How is OAuth 2 different from OAuth 1?

The previous explanations are all overly detailed and complicated IMO. Put simply, OAuth 2 delegates security to the HTTPS protocol. OAuth 1 did not require this and consequentially had alternative methods to deal with various attacks. These methods required the application to engage in certain security protocols which are complicated and can be difficult to implement. Therefore, it is simpler to just rely on the HTTPS for security so that application developers dont need to worry about it.

As to your other questions, the answer depends. Some services dont want to require the use of HTTPS, were developed before OAuth 2, or have some other requirement which may prevent them from using OAuth 2. Furthermore, there has been a lot of debate about the OAuth 2 protocol itself. As you can see, Facebook, Google, and a few others each have slightly varying versions of the protocols implemented. So some people stick with OAuth 1 because it is more uniform across the different platforms. Recently, the OAuth 2 protocol has been finalized but we have yet to see how its adoption will take.

Chrome dev tools fails to show response even the content returned has header Content-Type:text/html; charset=UTF-8

For those coming here from Google, and for whom the previous answers do not solve the mystery...

If you use XHR to make a server call, but do not return a response, this error will occur.

Example (from Nodejs/React but could equally be js/php):

App.tsx

const handleClickEvent = () => {
    fetch('/routeInAppjs?someVar=someValue&nutherVar=summat_else', {
        method: 'GET',
        mode: 'same-origin',
        credentials: 'include',
        headers: {
          'content-type': 'application/json',
          dataType: 'json',
        },
    }).then((response) => {
        console.log(response)
    });
}

App.js

app.route('/getAllPublicDatasheets').get(async function (req, res) {
    const { someVar, nutherVar } = req.query;
    console.log('Ending here without a return...')
});

Console.log will here report:

Failed to show response data

To fix, add the return response to bottom of your route (server-side):

res.json('Adding this below the console.log in App.js route will solve it.');

How to use performSelector:withObject:afterDelay: with primitive types in Cocoa?

Just wrap the float, boolean, int or similar in an NSNumber.

For structs, I don't know of a handy solution, but you could make a separate ObjC class that owns such a struct.

How to get current date time in milliseconds in android

Calendar calendar = Calendar.getInstance();
calendar.setTime(new Date());
int mSec = calendar.get(Calendar.MILLISECOND);

Set selected radio from radio group with a value

$("input[name='mygroup'][value='5']").attr("checked", true);

Loading existing .html file with android WebView

ok, that was my very stupid mistake. I post the answer here just in case someone has the same problem.

The correct path for files stored in assets folder is file:///android_asset/* (with no "s" for assets folder which i was always thinking it must have a "s").

And, mWebView.loadUrl("file:///android_asset/myfile.html"); works under all API levels.

I still not figure out why mWebView.loadUrl("file:///android_res/raw/myfile.html"); works only on API level 8. But it doesn't matter now.

Tips for debugging .htaccess rewrite rules

(Similar to Doin idea) To show what is being matched, I use this code

$keys = array_keys($_GET);
foreach($keys as $i=>$key){
    echo "$i => $key <br>";
}

Save it to r.php on the server root and then do some tests in .htaccess
For example, i want to match urls that do not start with a language prefix

RewriteRule ^(?!(en|de)/)(.*)$ /r.php?$1&$2 [L] #$1&$2&...
RewriteRule ^(.*)$ /r.php?nomatch [L] #report nomatch and exit

How can I delete a newline if it is the last character in a file?

POSIX SED:

'${/^$/d}'

$ - match last line


{ COMMANDS } - A group of commands may be enclosed between { and } characters. This is particularly useful when you want a group of commands to be triggered by a single address (or address-range) match.

Cross domain POST request is not sending cookie Ajax Jquery

Please note this doesn't solve the cookie sharing process, as in general this is bad practice.

You need to be using JSONP as your type:

From $.ajax documentation: Cross-domain requests and dataType: "jsonp" requests do not support synchronous operation.

$.ajax(
    { 
      type: "POST",
      url: "http://example.com/api/getlist.json",
      dataType: 'jsonp',
      xhrFields: {
           withCredentials: true
      },
      crossDomain: true,
      beforeSend: function(xhr) {
            xhr.setRequestHeader("Cookie", "session=xxxyyyzzz");
      },
      success: function(){
           alert('success');
      },
      error: function (xhr) {
             alert(xhr.responseText);
      }
    }
);

How do I enumerate through a JObject?

JObjects can be enumerated via JProperty objects by casting it to a JToken:

foreach (JProperty x in (JToken)obj) { // if 'obj' is a JObject
    string name = x.Name;
    JToken value = x.Value;
}

If you have a nested JObject inside of another JObject, you don't need to cast because the accessor will return a JToken:

foreach (JProperty x in obj["otherObject"]) { // Where 'obj' and 'obj["otherObject"]' are both JObjects
    string name = x.Name;
    JToken value = x.Value;
}

Oracle SQL - DATE greater than statement

you have to use the To_Date() function to convert the string to date ! http://www.techonthenet.com/oracle/functions/to_date.php

printf() formatting for hex

You could always use "%p" in order to display 8 bit hex numbers.

int main (void)
{
    uint8_t a;
    uint32_t b;
    a=15;
    b=a<<28;
    printf("%p", b);
    return 0;
}

Output:

0xf0000000

Add tooltip to font awesome icon

You should use 'title' attribute along with 'data-toogle' (bootstrap).

For example

<i class="fa fa-info" data-toggle="tooltip" title="Hooray!"></i>Hover over me

and do not forget to add the javascript to display the tooltip

<script>
    $(document).ready(function(){
        $('[data-toggle="tooltip"]').tooltip();   
    });
</script>

Changing the cursor in WPF sometimes works, sometimes doesn't

The following worked for me:

ForceCursor = true;
Cursor = Cursors.Wait;

HTML5 iFrame Seamless Attribute

Updated: October 2016

The seamless attribute no longer exists. It was originally pitched to be included in the first HTML5 spec, but subsequently dropped. An unrelated attribute of the same name made a brief cameo in the HTML5.1 draft, but that too was ditched mid-2016:

So I think the gist of it all both from the implementor side and the web-dev side is that seamless as-specced doesn’t seem to be what anybody wanted to begin with. Or at least it’s more than anybody actually wanted. And anyway like @annevk says, it’s seems a lot of it’s since been “overcome by events” in light of Shadow DOM.

In other words: purge the seamless attribute from your memory, and pretend it never existed.

For posterity's sake, here's my original answer from five years ago:

Original answer: April 2011

The attribute is in draft mode at the moment. For that reason, none of the current browsers are supporting it yet (as the implementation is subject to change). In the meantime, it's best just to use CSS to strip the borders/scrollbars from the iframe:

iframe[seamless]{
    background-color: transparent;
    border: 0px none transparent;
    padding: 0px;
    overflow: hidden;
}

There's more to the seamless attribute than what can be added with CSS: part of the reasoning behind the attribute was to allow nested content to inherit the same styles applied to the iframe (acting as though the embedded document was one big nested inside the element, for example).

Lastly, versions of Internet Explorer (8 and earlier) require additional attributes in order to remove the borders, scrollbars and background colour:

<iframe frameborder="0" allowtransparency="true" scrolling="no" src="..."></iframe>

Naturally, this doesn't validate. So it's up to you how to handle it. My (picky) approach would be to sniff the agent string and add the attributes for IE versions earlier than 9.

Hope that helps. :)

How to set JAVA_HOME in Linux for all users

None of the other answers were "sticking" for me in RHEL 7, even setting JAVA_HOME and PATH directly in /etc/profile or ~/.bash_profile would not work. Each time I tried to check if JAVA_HOME was set, it would come up blank:

$ echo $JAVA_HOME
    (<-- no output)

What I had to do was set up a script in /etc/profile.d/jdk_home.sh:

#!/bin/sh
export JAVA_HOME=/opt/ibm/java-x86_64-60/
export PATH=$JAVA_HOME/bin:$PATH

I initially neglected the first line (the #!/bin/sh), and it won't work without it.

Now it's working:

$ echo $JAVA_HOME
/opt/ibm/java-x86_64-60/

Concatenating date with a string in Excel

Thanks for the solution !

It works, but in a french Excel environment, you should apply something like

TEXTE(F2;"jj/mm/aaaa")

to get the date preserved as it is displayed in F2 cell, after concatenation. Best Regards

Fatal error compiling: invalid target release: 1.8 -> [Help 1]

You have set your %JAVA_HOME to jdk 1.7, but you are trying to compile using 1.8. Install jdk 1.8 and make sure your %JAVA_HOME points to that or drop the target release to 1.7.

invalid target release: 1.8

The target release refers to the jdk version.

Getting the class name from a static method in Java

If you want the entire package name with it, call:

String name = MyClass.class.getCanonicalName();

If you only want the last element, call:

String name = MyClass.class.getSimpleName();

Get the date (a day before current time) in Bash

if you have GNU date and i understood you correctly

$ date +%Y:%m:%d -d "yesterday"
2009:11:09

or

$ date +%Y:%m:%d -d "1 day ago"
2009:11:09

Displaying unicode symbols in HTML

Unlike proposed by Nicolas, the meta tag isn’t actually ignored by the browsers. However, the Content-Type HTTP header always has precedence over the presence of a meta tag in the document.

So make sure that you either send the correct encoding via the HTTP header, or don’t send this HTTP header at all (not recommended). The meta tag is mainly a fallback option for local documents which aren’t sent via HTTP traffic.

Using HTML entities should also be considered a workaround – that’s tiptoeing around the real problem. Configuring the web server properly prevents a lot of nuisance.

Length of string in bash

Here is couple of ways to calculate length of variable :

echo ${#VAR}
echo -n $VAR | wc -m
echo -n $VAR | wc -c
printf $VAR | wc -m
expr length $VAR
expr $VAR : '.*'

and to set the result in another variable just assign above command with back quote into another variable as following:

otherVar=`echo -n $VAR | wc -m`   
echo $otherVar

http://techopsbook.blogspot.in/2017/09/how-to-find-length-of-string-variable.html

How do I access properties of a javascript object if I don't know the names?

You can loop through keys like this:

for (var key in data) {
  console.log(key);
}

This logs "Name" and "Value".

If you have a more complex object type (not just a plain hash-like object, as in the original question), you'll want to only loop through keys that belong to the object itself, as opposed to keys on the object's prototype:

for (var key in data) {
  if (data.hasOwnProperty(key)) {
    console.log(key);
  }
}

As you noted, keys are not guaranteed to be in any particular order. Note how this differs from the following:

for each (var value in data) {
  console.log(value);
}

This example loops through values, so it would log Property Name and 0. N.B.: The for each syntax is mostly only supported in Firefox, but not in other browsers.

If your target browsers support ES5, or your site includes es5-shim.js (recommended), you can also use Object.keys:

var data = { Name: 'Property Name', Value: '0' };
console.log(Object.keys(data)); // => ["Name", "Value"]

and loop with Array.prototype.forEach:

Object.keys(data).forEach(function (key) {
  console.log(data[key]);
});
// => Logs "Property Name", 0

Keyboard shortcuts are not active in Visual Studio with Resharper installed

For me the issue was in Resharper License. It has been delinked from my account for some reason and it said that the license is invalid. When I linked it again to my JetBrains account it started to work properly after a few minutes.

Python's equivalent of && (logical-and) in an if-statement

Two comments:

  • Use and and or for logical operations in Python.
  • Use 4 spaces to indent instead of 2. You will thank yourself later because your code will look pretty much the same as everyone else's code. See PEP 8 for more details.

RuntimeWarning: DateTimeField received a naive datetime

If you are trying to transform a naive datetime into a datetime with timezone in django, here is my solution:

>>> import datetime
>>> from django.utils import timezone
>>> t1 = datetime.datetime.strptime("2019-07-16 22:24:00", "%Y-%m-%d %H:%M:%S")
>>> t1
    datetime.datetime(2019, 7, 16, 22, 24)
>>> current_tz = timezone.get_current_timezone()
>>> t2 = current_tz.localize(t1)
>>> t2
    datetime.datetime(2019, 7, 16, 22, 24, tzinfo=<DstTzInfo 'Asia/Shanghai' CST+8:00:00 STD>)
>>>

t1 is a naive datetime and t2 is a datetime with timezone in django's settings.

How to Set Focus on JTextField?

While yourTextField.requestFocus() is A solution, it is not the best since in the official Java documentation this is discourage as the method requestFocus() is platform dependent.

The documentation says:

Note that the use of this method is discouraged because its behavior is platform dependent. Instead we recommend the use of requestFocusInWindow().

Use yourJTextField.requestFocusInWindow() instead.

How can I stop a running MySQL query?

Just to add

KILL QUERY **Id** where Id is connection id from show processlist

is more preferable if you are do not want to kill the connection usually when running from some application.

For more details you can read mysql doc here

What is ADT? (Abstract Data Type)

ADT is a set of objects and operations, no where in an ADT’s definitions is there any mention of how the set of operations is implemented. Programmers who use collections only need to know how to instantiate and access data in some pre-determined manner, without concerns for the details of the collections implementations. In other words, from a user’s perspective, a collection is an abstraction, and for this reason, in computer science, some collections are referred to as abstract data types (ADTs). The user is only concern with learning its interface, or the set of operations its performs...more

How to make a simple modal pop up form using jquery and html?

I have placed here complete bins for above query. you can check demo link too.

Demo: http://codebins.com/bin/4ldqp78/2/How%20to%20make%20a%20simple%20modal%20pop

HTML

<div id="panel">
  <input type="button" class="button" value="1" id="btn1">
  <input type="button" class="button" value="2" id="btn2">
  <input type="button" class="button" value="3" id="btn3">
  <br>
  <input type="text" id="valueFromMyModal">
  <!-- Dialog Box-->
  <div class="dialog" id="myform">
    <form>
      <label id="valueFromMyButton">
      </label>
      <input type="text" id="name">
      <div align="center">
        <input type="button" value="Ok" id="btnOK">
      </div>
    </form>
  </div>
</div>

JQuery

$(function() {
    $(".button").click(function() {
        $("#myform #valueFromMyButton").text($(this).val().trim());
        $("#myform input[type=text]").val('');
        $("#myform").show(500);
    });
    $("#btnOK").click(function() {
        $("#valueFromMyModal").val($("#myform input[type=text]").val().trim());
        $("#myform").hide(400);
    });
});

CSS

.button{
  border:1px solid #333;
  background:#6479fd;
}
.button:hover{
  background:#a4a9fd;
}
.dialog{
  border:5px solid #666;
  padding:10px;
  background:#3A3A3A;
  position:absolute;
  display:none;
}
.dialog label{
  display:inline-block;
  color:#cecece;
}
input[type=text]{
  border:1px solid #333;
  display:inline-block;
  margin:5px;
}
#btnOK{
  border:1px solid #000;
  background:#ff9999;
  margin:5px;
}

#btnOK:hover{
  border:1px solid #000;
  background:#ffacac;
}

Demo: http://codebins.com/bin/4ldqp78/2/How%20to%20make%20a%20simple%20modal%20pop

Regex: Remove lines containing "help", etc

This is also possible with Notepad++:

  • Go to the search menu, Ctrl + F, and open the Mark tab.
  • Check Bookmark line (if there is no Mark tab update to the current version).

  • Enter your search term and click Mark All

    • All lines containing the search term are bookmarked.
  • Now go to the menu SearchBookmarkRemove Bookmarked lines

  • Done.

Show/hide 'div' using JavaScript

You can also use the jQuery JavaScript framework:

To Hide Div Block

$(".divIDClass").hide();

To show Div Block

$(".divIDClass").show();

How can I add new item to the String array?

Simple answer: You can't. An array is fixed size in Java. You'll want to use a List<String>.

Alternatively, you could create an array of fixed size and put things in it:

String[] array = new String[2];
array[0] = "Hello";
array[1] = "World!";

Adding a column to an existing table in a Rails migration

When I've done this, rather than fiddling the original migration, I create a new one with just the add column in the up section and a drop column in the down section.

You can change the original and rerun it if you migrate down between, but in this case I think that's made a migration that won't work properly.

As currently posted, you're adding the column and then creating the table.

If you change the order it might work. Or, as you're modifying an existing migration, just add it to the create table instead of doing a separate add column.

Is it possible to set UIView border properties from interface builder?

Rich86Man's answer is correct, but you can use categories to proxy properties such as layer.borderColor. (From the ConventionalC CocoaPod)

CALayer+XibConfiguration.h:

#import <QuartzCore/QuartzCore.h>
#import <UIKit/UIKit.h>

@interface CALayer(XibConfiguration)

// This assigns a CGColor to borderColor.
@property(nonatomic, assign) UIColor* borderUIColor;

@end

CALayer+XibConfiguration.m:

#import "CALayer+XibConfiguration.h"

@implementation CALayer(XibConfiguration)

-(void)setBorderUIColor:(UIColor*)color
{
    self.borderColor = color.CGColor;
}

-(UIColor*)borderUIColor
{
    return [UIColor colorWithCGColor:self.borderColor];
}

@end

Interface Builder

layer.borderUIColor

The result will be apparent during runtime, not in Xcode.

Edit: You also need to set layer.borderWidth to at least 1 to see the border with the chosen color.

In Swift 2.0:

extension CALayer {
    var borderUIColor: UIColor {
        set {
            self.borderColor = newValue.CGColor
        }

        get {
            return UIColor(CGColor: self.borderColor!)
        }
    }
}

In Swift 3.0:

extension CALayer {
    var borderUIColor: UIColor {
        set {
            self.borderColor = newValue.cgColor
        }

        get {
            return UIColor(cgColor: self.borderColor!)
        }
    }
}

Good Java graph algorithm library?

JGraph from http://mmengineer.blogspot.com/2009/10/java-graph-floyd-class.html

Provides a powerfull software to work with graphs (direct or undirect). Also generates Graphivz code, you can see graphics representations. You can put your own code algorithms into pakage, for example: backtracking code. The package provide some algorithms: Dijkstra, backtracking minimun path cost, ect..

html "data-" attribute as javascript parameter

you might use default parameters in your function and then just pass the entire dataset itself, since the dataset is already a DOMStringMap Object

<div data-uid="aaa" data-name="bbb" data-value="ccc"
onclick="fun(this.dataset)">

<script>
const fun = ({uid:'ddd', name:'eee', value:'fff', other:'default'} = {}) { 
    // 
}
</script>

that way, you can deal with any data-values that got set in the html tag, or use defaults if they weren't set - that kind of thing

maybe not in this situation, but in others, it might be advantageous to put all your preferences in a single data-attribute

<div data-all='{"uid":"aaa","name":"bbb","value":"ccc"}'
onclick="fun(JSON.parse(this.dataset.all))">

there are probably more terse ways of doing that, if you already know certain things about the order of the data

<div data-all="aaa,bbb,ccc" onclick="fun(this.dataset.all.split(','))">

How can I solve "Non-static method xxx:xxx() should not be called statically in PHP 5.4?

I don't suggest you just hidding the stricts errors on your project. Intead, you should turn your method to static or try to creat a new instance of the object:

$var = new YourClass();
$var->method();

You can also use the new way to do the same since PHP 5.4:

(new YourClass)->method();

I hope it helps you!

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

You can use either - which means most people opt for "+" as it's more human readable.

Running Python on Windows for Node.js dependencies

If you're trying to use this on Cygwin, then you need to follow the instructions in this answer. (It's a problem how Cygwin treats Windows symlinks.)

JavaScript and getElementById for multiple elements with the same ID

As others have stated, you shouldn't have the same ID more than once in your HTML, however... elements with an ID are attached to the document object and to window on Internet Explorer. Refer to:

Do DOM tree elements with ids become global variables?

If more than one element with the same ID exists in your HTML, this property is attached as an array. I'm sorry, but I don't know where to look if this is the standard behavior or at least you get the same behavior between browsers, which I doubt.

How can I use/create dynamic template to compile dynamic Component with Angular 2.0?

2019 June answer

Great news! It seems that the @angular/cdk package now has first-class support for portals!

As of the time of writing, I didn't find the above official docs particularly helpful (particularly with regard to sending data into and receiving events from the dynamic components). In summary, you will need to:

Step 1) Update your AppModule

Import PortalModule from the @angular/cdk/portal package and register your dynamic component(s) inside entryComponents

@NgModule({
  declarations: [ ..., AppComponent, MyDynamicComponent, ... ]
  imports:      [ ..., PortalModule, ... ],
  entryComponents: [ ..., MyDynamicComponent, ... ]
})
export class AppModule { }

Step 2. Option A: If you do NOT need to pass data into and receive events from your dynamic components:

@Component({
  selector: 'my-app',
  template: `
    <button (click)="onClickAddChild()">Click to add child component</button>
    <ng-template [cdkPortalOutlet]="myPortal"></ng-template>
  `
})
export class AppComponent  {
  myPortal: ComponentPortal<any>;
  onClickAddChild() {
    this.myPortal = new ComponentPortal(MyDynamicComponent);
  }
}

@Component({
  selector: 'app-child',
  template: `<p>I am a child.</p>`
})
export class MyDynamicComponent{
}

See it in action

Step 2. Option B: If you DO need to pass data into and receive events from your dynamic components:

// A bit of boilerplate here. Recommend putting this function in a utils 
// file in order to keep your component code a little cleaner.
function createDomPortalHost(elRef: ElementRef, injector: Injector) {
  return new DomPortalHost(
    elRef.nativeElement,
    injector.get(ComponentFactoryResolver),
    injector.get(ApplicationRef),
    injector
  );
}

@Component({
  selector: 'my-app',
  template: `
    <button (click)="onClickAddChild()">Click to add random child component</button>
    <div #portalHost></div>
  `
})
export class AppComponent {

  portalHost: DomPortalHost;
  @ViewChild('portalHost') elRef: ElementRef;

  constructor(readonly injector: Injector) {
  }

  ngOnInit() {
    this.portalHost = createDomPortalHost(this.elRef, this.injector);
  }

  onClickAddChild() {
    const myPortal = new ComponentPortal(MyDynamicComponent);
    const componentRef = this.portalHost.attach(myPortal);
    setTimeout(() => componentRef.instance.myInput 
      = '> This is data passed from AppComponent <', 1000);
    // ... if we had an output called 'myOutput' in a child component, 
    // this is how we would receive events...
    // this.componentRef.instance.myOutput.subscribe(() => ...);
  }
}

@Component({
  selector: 'app-child',
  template: `<p>I am a child. <strong>{{myInput}}</strong></p>`
})
export class MyDynamicComponent {
  @Input() myInput = '';
}

See it in action

Android ListView with onClick items

listview.setOnItemClickListener(new OnItemClickListener(){

//setting onclick to items in the listview.

@Override
public void onItemClick(AdapterView<?>adapter,View v, int position){
Intent intent;
switch(position){

// case 0 is the first item in the listView.

  case 0:
    intent = new Intent(Activity.this,firstActivity.class);
    break;
//case 1 is the second item in the listView.

  case 1:
    intent = new Intent(Activity.this,secondActivity.class);
    break;
 case 2:
    intent = new Intent(Activity.this,thirdActivity.class);
    break;
//add more if you have more items in listView
startActivity(intent);
}

});

How to grant "grant create session" privilege?

You can grant system privileges with or without the admin option. The default being without admin option.

GRANT CREATE SESSION TO username

or with admin option:

GRANT CREATE SESSION TO username WITH ADMIN OPTION

The Grantee with the ADMIN OPTION can grant and revoke privileges to other users

SQL Add foreign key to existing column

MySQL / SQL Server / Oracle / MS Access:

ALTER TABLE Orders
ADD FOREIGN KEY (P_Id)
REFERENCES Persons(P_Id)

To allow naming of a FOREIGN KEY constraint, and for defining a FOREIGN KEY constraint on multiple columns, use the following SQL syntax:

MySQL / SQL Server / Oracle / MS Access:

ALTER TABLE Orders
ADD CONSTRAINT fk_PerOrders
FOREIGN KEY (P_Id)
REFERENCES Persons(P_Id)

How to change the Title of the window in Qt?

I know this is years later but I ran into the same problem. The solution I found was to change the window title in main.cpp. I guess once the w.show(); is called the window title can no longer be changed. In my case I just wanted the title to reflect the current directory and it works.

int main(int argc, char *argv[]) 
{
QApplication a(argc, argv);
MainWindow w;
w.setWindowTitle(QDir::currentPath());
w.show();

return a.exec();
}

how do I create an array in jquery?

Here is an example that I used.

<script>
  $(document).ready(function(){
      var array =  $.makeArray(document.getElementsByTagName(“p”));
      array.reverse(); 
      $(array).appendTo(document.body);
  });
</script>

can we use xpath with BeautifulSoup?

Maybe you can try the following without XPath

from simplified_scrapy.simplified_doc import SimplifiedDoc 
html = '''
<html>
<body>
<div>
    <h1>Example Domain</h1>
    <p>This domain is for use in illustrative examples in documents. You may use this
    domain in literature without prior coordination or asking for permission.</p>
    <p><a href="https://www.iana.org/domains/example">More information...</a></p>
</div>
</body>
</html>
'''
# What XPath can do, so can it
doc = SimplifiedDoc(html)
# The result is the same as doc.getElementByTag('body').getElementByTag('div').getElementByTag('h1').text
print (doc.body.div.h1.text)
print (doc.div.h1.text)
print (doc.h1.text) # Shorter paths will be faster
print (doc.div.getChildren())
print (doc.div.getChildren('p'))

Jackson how to transform JsonNode to ArrayNode without casting?

Is there a method equivalent to getJSONArray in org.json so that I have proper error handling in case it isn't an array?

It depends on your input; i.e. the stuff you fetch from the URL. If the value of the "datasets" attribute is an associative array rather than a plain array, you will get a ClassCastException.

But then again, the correctness of your old version also depends on the input. In the situation where your new version throws a ClassCastException, the old version will throw JSONException. Reference: http://www.json.org/javadoc/org/json/JSONObject.html#getJSONArray(java.lang.String)

SQL Error: 0, SQLState: 08S01 Communications link failure

The communication link between the driver and the data source to which the driver was attempting to connect failed before the function completed processing. So usually its a network error. This could be caused by packet drops or badly configured Firewall/Switch.

How to set an image's width and height without stretching it?

CSS3 object-fit

Am not sure how far its been implemented by webkit, IE and firefox. But Opera works like magic

object-fit works with SVG content, but the same effect can also be achieved by setting the preserveAspectRatio="" attribute in the SVG itself.

img {
  height: 100px;
  width: 100px;
  -o-object-fit: contain;
}

Chris Mills demo's it here http://dev.opera.com/articles/view/css3-object-fit-object-position/

Get filename in batch for loop

The answer by @AKX works on the command line, but not within a batch file. Within a batch file, you need an extra %, like this:

@echo off
for /R TutorialSteps %%F in (*.py) do echo %%~nF

Using Vim's tabs like buffers

I use buffers like tabs, using the BufExplorer plugin and a few macros:

" CTRL+b opens the buffer list
map <C-b> <esc>:BufExplorer<cr>

" gz in command mode closes the current buffer
map gz :bdelete<cr>

" g[bB] in command mode switch to the next/prev. buffer
map gb :bnext<cr>
map gB :bprev<cr>

With BufExplorer you don't have a tab bar at the top, but on the other hand it saves space on your screen, plus you can have an infinite number of files/buffers open and the buffer list is searchable...

How to get the file path from HTML input form in Firefox 3

Simply you cannot do it with FF3.

The other option could be using applet or other controls to select and upload files.

How to pass a single object[] to a params object[]

This is a one line solution involving LINQ.

var elements = new String[] { "1", "2", "3" };
Foo(elements.Cast<object>().ToArray())

Custom alert and confirm box in jquery

jQuery UI has it's own elements, but jQuery alone hasn't.

http://jqueryui.com/dialog/

Working example:

<!doctype html>

<html lang="en">
<head>
  <meta charset="utf-8" />
  <title>jQuery UI Dialog - Default functionality</title>
  <link rel="stylesheet" href="http://code.jquery.com/ui/1.10.3/themes/smoothness/jquery-ui.css" />
  <script src="http://code.jquery.com/jquery-1.9.1.js"></script>
  <script src="http://code.jquery.com/ui/1.10.3/jquery-ui.js"></script>
  <link rel="stylesheet" href="/resources/demos/style.css" />
  <script>
  $(function() {
    $( "#dialog" ).dialog();
  });
  </script>
</head>
<body>

<div id="dialog" title="Basic dialog">
  <p>This is the default dialog which is useful for displaying information. The dialog window can be moved, resized and closed with the 'x' icon.</p>
</div>


</body>
</html>

Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding. The statement has been terminated

Timeout expired because the sql query is taking more time than you set in sqlCommand.CommandTimeout property.

Obviously you can increase CommandTimeout to solve this issue but before doing that you must optimize your query by adding index. If you run your query in Sql server management studio including actual execution plan then Sql server management studio will suggest you proper index. Most of the case you will get rid of timeout issue if you can optimize your query.

Array of Matrices in MATLAB

if you know what unknown is,

you can do something like

myArray = zeros(2,2);
for i: 1:unknown
  myArray(:,i) = zeros(x,y);
end

However it has been a while since I last used matlab. so this page might shed some light on the matter :

http://www.mathworks.com/access/helpdesk/help/techdoc/index.html?/access/helpdesk/help/techdoc/matlab_prog/f1-86528.html

Angularjs $q.all

$http is a promise too, you can make it simpler:

return $q.all(tasks.map(function(d){
        return $http.post('upload/tasks',d).then(someProcessCallback, onErrorCallback);
    }));

In vb.net, how to get the column names from a datatable

' i modify the code for Datatable 

For Each c as DataColumn in dt.Columns
 For j=0 To _dataTable.Columns.Count-1
            xlWorksheet.Cells (i+1, j+1) = _dataTable.Columns(j).ColumnName
Next
Next

Hope this could be help!

What does "for" attribute do in HTML <label> tag?

The for attribute shows that this label stands for related input field, or check box or radio button or any other data entering field associated with it. for example

<li>
    <label>{translate:blindcopy}</label>
    <a class="" href="#" title="{translate:savetemplate}" onclick="" ><i class="fa fa-list" class="button" ></i></a> &nbsp 
            <input type="text" id="BlindCopy" name="BlindCopy" class="splitblindcopy" />

</li>

How to use this boolean in an if statement?

additionally you can just write

if(stop)
{
        sb.append("y");
        getWhoozitYs();
}

What does "ulimit -s unlimited" do?

stack size can indeed be unlimited. _STK_LIM is the default, _STK_LIM_MAX is something that differs per architecture, as can be seen from include/asm-generic/resource.h:

/*
 * RLIMIT_STACK default maximum - some architectures override it:
 */
#ifndef _STK_LIM_MAX
# define _STK_LIM_MAX           RLIM_INFINITY
#endif

As can be seen from this example generic value is infinite, where RLIM_INFINITY is, again, in generic case defined as:

/*
 * SuS says limits have to be unsigned.
 * Which makes a ton more sense anyway.
 *
 * Some architectures override this (for compatibility reasons):
 */
#ifndef RLIM_INFINITY
# define RLIM_INFINITY          (~0UL)
#endif

So I guess the real answer is - stack size CAN be limited by some architecture, then unlimited stack trace will mean whatever _STK_LIM_MAX is defined to, and in case it's infinity - it is infinite. For details on what it means to set it to infinite and what implications it might have, refer to the other answer, it's way better than mine.

How to use OrderBy with findAll in Spring Data

Yes you can sort using query method in Spring Data.

Ex:ascending order or descending order by using the value of the id field.

Code:

  public interface StudentDAO extends JpaRepository<StudentEntity, Integer> {
    public findAllByOrderByIdAsc();   
}

alternative solution:

    @Repository
public class StudentServiceImpl implements StudentService {
    @Autowired
    private StudentDAO studentDao;

    @Override
    public List<Student> findAll() {
        return studentDao.findAll(orderByIdAsc());
    }
private Sort orderByIdAsc() {
    return new Sort(Sort.Direction.ASC, "id")
                .and(new Sort(Sort.Direction.ASC, "name"));
}
}

Spring Data Sorting: Sorting

Initial size for the ArrayList

If you want a list with a predefined size you can also use:

List<Integer> arr = Arrays.asList(new Integer[10]);

Iterating over ResultSet and adding its value in an ArrayList

Just for the fun, I'm offering an alternative solution using jOOQ and Java 8. Instead of using jOOQ, you could be using any other API that maps JDBC ResultSet to List, such as Spring JDBC or Apache DbUtils, or write your own ResultSetIterator:

jOOQ 3.8 or less

List<Object> list =
DSL.using(connection)
   .fetch("SELECT col1, col2, col3, ...")
   .stream()
   .flatMap(r -> Arrays.stream(r.intoArray()))
   .collect(Collectors.toList());

jOOQ 3.9

List<Object> list =
DSL.using(connection)
   .fetch("SELECT col1, col2, col3, ...")
   .stream()
   .flatMap(Record::intoStream)
   .collect(Collectors.toList());

(Disclaimer, I work for the company behind jOOQ)

Selecting all text in HTML text input when clicked

If you are looking for a pure vanilla javascript method, you can also use:

document.createRange().selectNodeContents( element );

This will select all the text and is supported by all major browsers.

To trigger the selection on focus, you just need to add the event listener like so:

document.querySelector( element ).addEventListener( 'focusin', function () {

    document.createRange().selectNodeContents( this );

} );

If you want to place it inline in your HTML, then you can do this:

<input type="text" name="myElement" onFocus="document.createRange().selectNodeContents(this)'" value="Some text to select" />

This is just another option. There appears to be a few ways of doing this. (document.execCommand("selectall") as mentioned here as well)

_x000D_
_x000D_
document.querySelector('#myElement1').addEventListener('focusin', function() {

  document.createRange().selectNodeContents(this);

});
_x000D_
<p>Cicking inside field will not trigger the selection, but tabbing into the fields will.</p>
<label for="">JS File Example<label><br>
<input id="myElement1" value="This is some text" /><br>
<br>
<label for="">Inline example</label><br>
<input id="myElement2" value="This also is some text" onfocus="document.createRange().selectNodeContents( this );" />
_x000D_
_x000D_
_x000D_

File being used by another process after using File.Create()

File.Create returns a FileStream. You need to close that when you have written to the file:

using (FileStream fs = File.Create(path, 1024)) 
        {
            Byte[] info = new UTF8Encoding(true).GetBytes("This is some text in the file.");
            // Add some information to the file.
            fs.Write(info, 0, info.Length);
        }

You can use using for automatically closing the file.

convert string to char*

There are many ways. Here are at least five:

/*
 * An example of converting std::string to (const)char* using five
 * different methods. Error checking is emitted for simplicity.
 *
 * Compile and run example (using gcc on Unix-like systems):
 *
 *  $ g++ -Wall -pedantic -o test ./test.cpp
 *  $ ./test
 *  Original string (0x7fe3294039f8): hello
 *  s1 (0x7fe3294039f8): hello
 *  s2 (0x7fff5dce3a10): hello
 *  s3 (0x7fe3294000e0): hello
 *  s4 (0x7fe329403a00): hello
 *  s5 (0x7fe329403a10): hello
 */

#include <alloca.h>
#include <string>
#include <cstring>

int main()
{
    std::string s0;
    const char *s1;
    char *s2;
    char *s3;
    char *s4;
    char *s5;

    // This is the initial C++ string.
    s0 = "hello";

    // Method #1: Just use "c_str()" method to obtain a pointer to a
    // null-terminated C string stored in std::string object.
    // Be careful though because when `s0` goes out of scope, s1 points
    // to a non-valid memory.
    s1 = s0.c_str();

    // Method #2: Allocate memory on stack and copy the contents of the
    // original string. Keep in mind that once a current function returns,
    // the memory is invalidated.
    s2 = (char *)alloca(s0.size() + 1);
    memcpy(s2, s0.c_str(), s0.size() + 1);

    // Method #3: Allocate memory dynamically and copy the content of the
    // original string. The memory will be valid until you explicitly
    // release it using "free". Forgetting to release it results in memory
    // leak.
    s3 = (char *)malloc(s0.size() + 1);
    memcpy(s3, s0.c_str(), s0.size() + 1);

    // Method #4: Same as method #3, but using C++ new/delete operators.
    s4 = new char[s0.size() + 1];
    memcpy(s4, s0.c_str(), s0.size() + 1);

    // Method #5: Same as 3 but a bit less efficient..
    s5 = strdup(s0.c_str());

    // Print those strings.
    printf("Original string (%p): %s\n", s0.c_str(), s0.c_str());
    printf("s1 (%p): %s\n", s1, s1);
    printf("s2 (%p): %s\n", s2, s2);
    printf("s3 (%p): %s\n", s3, s3);
    printf("s4 (%p): %s\n", s4, s4);
    printf("s5 (%p): %s\n", s5, s5);

    // Release memory...
    free(s3);
    delete [] s4;
    free(s5);
}

How to outline text in HTML / CSS

from: Outline effect to text

.strokeme
{
    color: white;
    text-shadow:
    -1px -1px 0 #000,
    1px -1px 0 #000,
    -1px 1px 0 #000,
    1px 1px 0 #000;  
}

How to visualize an XML schema?

XSD Diagram is free (GNU open license), doesn't need to be built, and gives an interactive diagram. You just open the file and Add the types you want on the (initially blank) diagram. Pretty straight forward.

enter image description here

Align text in a table header

In HTML5, the easiest, and fastest, way to center your <th>THcontent</th> is to add a colspan like this:

<th colspan="3">Thcontent</th> 

This will work if your table is three columns. So if you have a four-column table, add a colspan of 4, etc.

You can manage the location furthermore in the CSS file while you have put your colspan in HTML like I said.

th { 
    text-align: center; /* Or right or left */
}

MySQL - How to parse a string value to DATETIME format inside an INSERT statement?

Use MySQL's STR_TO_DATE() function to parse the string that you're attempting to insert:

INSERT INTO tblInquiry (fldInquiryReceivedDateTime) VALUES
  (STR_TO_DATE('5/15/2012 8:06:26 AM', '%c/%e/%Y %r'))

How to download an entire directory and subdirectories using wget?

This will help

wget -m -np -c --level 0 --no-check-certificate -R"index.html*"http://www.your-websitepage.com/dir

PHP date time greater than today

You are not comparing dates. You are comparing strings. In the world of string comparisons, 09/17/2015 > 01/02/2016 because 09 > 01. You need to either put your date in a comparable string format or compare DateTime objects which are comparable.

<?php
 $date_now = date("Y-m-d"); // this format is string comparable

if ($date_now > '2016-01-02') {
    echo 'greater than';
}else{
    echo 'Less than';
}

Demo

Or

<?php
 $date_now = new DateTime();
 $date2    = new DateTime("01/02/2016");

if ($date_now > $date2) {
    echo 'greater than';
}else{
    echo 'Less than';
}

Demo

Opening Chrome From Command Line

if you want to open incognito window, put the command below:

start chrome /incognito

how to query child objects in mongodb

Assuming your "states" collection is like:

{"name" : "Spain", "cities" : [ { "name" : "Madrid" }, { "name" : null } ] }
{"name" : "France" }

The query to find states with null cities would be:

db.states.find({"cities.name" : {"$eq" : null, "$exists" : true}});

It is a common mistake to query for nulls as:

db.states.find({"cities.name" : null});

because this query will return all documents lacking the key (in our example it will return Spain and France). So, unless you are sure the key is always present you must check that the key exists as in the first query.

How to plot two histograms together in R?

Plotly's R API might be useful for you. The graph below is here.

library(plotly)
#add username and key
p <- plotly(username="Username", key="API_KEY")
#generate data
x0 = rnorm(500)
x1 = rnorm(500)+1
#arrange your graph
data0 = list(x=x0,
         name = "Carrots",
         type='histogramx',
         opacity = 0.8)

data1 = list(x=x1,
         name = "Cukes",
         type='histogramx',
         opacity = 0.8)
#specify type as 'overlay'
layout <- list(barmode='overlay',
               plot_bgcolor = 'rgba(249,249,251,.85)')  
#format response, and use 'browseURL' to open graph tab in your browser.
response = p$plotly(data0, data1, kwargs=list(layout=layout))

url = response$url
filename = response$filename

browseURL(response$url)

Full disclosure: I'm on the team.

Graph

Get an OutputStream into a String

I like the Apache Commons IO library. Take a look at its version of ByteArrayOutputStream, which has a toString(String enc) method as well as toByteArray(). Using existing and trusted components like the Commons project lets your code be smaller and easier to extend and repurpose.

How to insert newline in string literal?

Here, Environment.NewLine doesn't worked.

I put a "<br/>" in a string and worked.

Ex:

ltrYourLiteral.Text = "First line.<br/>Second Line.";

Retrieving values from nested JSON Object

To see all keys of Jsonobject use this

    String JSON = "{\"LanguageLevels\":{\"1\":\"Pocz\\u0105tkuj\\u0105cy\",\"2\":\"\\u015arednioZaawansowany\",\"3\":\"Zaawansowany\",\"4\":\"Ekspert\"}}\n";
    JSONObject obj = new JSONObject(JSON);
    Iterator iterator = obj.keys();
    String key = null;
    while (iterator.hasNext()) {
        key = (String) iterator.next();
        System.out.pritnln(key);
    } 

Copy table from one database to another

Assuming that you want different names for the tables.

If you are using PHPmyadmin you can use their SQL option in the menu. Then you simply copy the SQL-code from the first table and paste it into the new table.

That worked out for me when I was moving from localhost to a webhost. Hope it works for you!

WARNING: Setting property 'source' to 'org.eclipse.jst.jee.server:appname' did not find a matching property

You can change the eclipse tomcat server configuration. Open the server view, double click on you server to open server configuration. Then click to activate "Publish module contents to separate XML files". Finally, restart your server, the message must disappear.

Source: http://www.albeesonline.com/blog/2008/11/29/warning-setpropertiesruleserverserviceenginehostcontext-setting-property/

Is it safe to expose Firebase apiKey to the public?

I am not convinced to expose security/config keys to client. I would not call it secure, not because some one can steal all private information from first day, because someone can make excessive request, and drain your quota and make you owe to Google a lot of money.

You need to think about many concepts from restricting people not to access where they are not supposed to be, DOS attacks etc.

I would more prefer the client first will hit to your web server, there you put what ever first hand firewall, captcha , cloudflare, custom security in between the client and server, or between server and firebase and you are good to go. At least you can first stop suspect activity before it reaches to firebase. You will have much more flexibility.

I only see one good usage scenario for using client based config for internal usages. For example, you have internal domain, and you are pretty sure outsiders cannot access there, so you can setup environment like browser -> firebase type.

node.js: cannot find module 'request'

I tried installing the module locally with version and it worked!!

npm install request@^2.*

Thanks.

top nav bar blocking top content of the page

The bootstrap v4 starter template css uses:

body {
  padding-top: 5rem;
}

Replacing few values in a pandas dataframe column with another value

Just wanted to show that there is no performance difference between the 2 main ways of doing it:

df = pd.DataFrame(np.random.randint(0,10,size=(100, 4)), columns=list('ABCD'))

def loc():
    df1.loc[df1["A"] == 2] = 5
%timeit loc
19.9 ns ± 0.0873 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)


def replace():
    df2['A'].replace(
        to_replace=2,
        value=5,
        inplace=True
    )
%timeit replace
19.6 ns ± 0.509 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)

Make error: missing separator

In my case error caused next. I've tried to execute commands globally i.e outside of any target.

UPD. To run command globally one must be properly formed. For example command

ln -sf ../../user/curl/$SRC_NAME ./$SRC_NAME

would become:

$(shell ln -sf ../../user/curl/$(SRC_NAME) ./$(SRC_NAME))

How can I convince IE to simply display application/json rather than offer to download it?

Changing IE's JSON mime-type settings will effect the way IE treats all JSON responses.

Changing the mime-type header to text/html will effectively tell any browser that the JSON response you are returning is not JSON but plain text.

Neither options are preferable.

Instead you would want to use a plugin or tool like the above mentioned Fiddler or any other network traffic inspector proxy where you can choose each time how to process the JSON response.

How to make a rest post call from ReactJS code?

Here is a the list of ajax libraries comparison based on the features and support. I prefer to use fetch for only client side development or isomorphic-fetch for using in both client side and server side development.

For more information on isomorphic-fetch vs fetch

How can I clear event subscriptions in C#?

Instead of adding and removing callbacks manually and having a bunch of delegate types declared everywhere:

// The hard way
public delegate void ObjectCallback(ObjectType broadcaster);

public class Object
{
    public event ObjectCallback m_ObjectCallback;
    
    void SetupListener()
    {
        ObjectCallback callback = null;
        callback = (ObjectType broadcaster) =>
        {
            // one time logic here
            broadcaster.m_ObjectCallback -= callback;
        };
        m_ObjectCallback += callback;

    }
    
    void BroadcastEvent()
    {
        m_ObjectCallback?.Invoke(this);
    }
}

You could try this generic approach:

public class Object
{
    public Broadcast<Object> m_EventToBroadcast = new Broadcast<Object>();

    void SetupListener()
    {
        m_EventToBroadcast.SubscribeOnce((ObjectType broadcaster) => {
            // one time logic here
        });
    }

    ~Object()
    {
        m_EventToBroadcast.Dispose();
        m_EventToBroadcast = null;
    }

    void BroadcastEvent()
    {
        m_EventToBroadcast.Broadcast(this);
    }
}


public delegate void ObjectDelegate<T>(T broadcaster);
public class Broadcast<T> : IDisposable
{
    private event ObjectDelegate<T> m_Event;
    private List<ObjectDelegate<T>> m_SingleSubscribers = new List<ObjectDelegate<T>>();

    ~Broadcast()
    {
        Dispose();
    }

    public void Dispose()
    {
        Clear();
        System.GC.SuppressFinalize(this);
    }

    public void Clear()
    {
        m_SingleSubscribers.Clear();
        m_Event = delegate { };
    }

    // add a one shot to this delegate that is removed after first broadcast
    public void SubscribeOnce(ObjectDelegate<T> del)
    {
        m_Event += del;
        m_SingleSubscribers.Add(del);
    }

    // add a recurring delegate that gets called each time
    public void Subscribe(ObjectDelegate<T> del)
    {
        m_Event += del;
    }

    public void Unsubscribe(ObjectDelegate<T> del)
    {
        m_Event -= del;
    }

    public void Broadcast(T broadcaster)
    {
        m_Event?.Invoke(broadcaster);
        for (int i = 0; i < m_SingleSubscribers.Count; ++i)
        {
            Unsubscribe(m_SingleSubscribers[i]);
        }
        m_SingleSubscribers.Clear();
    }
}

Auto-fit TextView for Android

If you are looking for something easier:

 public MyTextView extends TextView{

    public void resize(String text, float textViewWidth, float textViewHeight) {
       Paint p = new Paint();
       Rect bounds = new Rect();
       p.setTextSize(1);
       p.getTextBounds(text, 0, text.length(), bounds);
       float widthDifference = (textViewWidth)/bounds.width();
       float heightDifference = (textViewHeight);
       textSize = Math.min(widthDifference, heightDifference);
       setTextSize(TypedValue.COMPLEX_UNIT_PX, textSize);
}

How to add Class in <li> using wp_nav_menu() in Wordpress?

Without walker menu it's not possible to directly add it. You can, however, add it by javascript.

$('#menu > li').addClass('class_name');

Is it possible to run an .exe or .bat file on 'onclick' in HTML

You can not run/execute an .exe file that is in the users local machine or through a site. The user must first download the exe file and then run the executable file.
So there is no possible way

The following code works only when the EXE is Present in the User's Machine.

<a href = "C:\folder_name\program.exe">

Size-limited queue that holds last N elements in Java

I like @FractalizeR solution. But I would in addition keep and return the value from super.add(o)!

public class LimitedQueue<E> extends LinkedList<E> {

    private int limit;

    public LimitedQueue(int limit) {
        this.limit = limit;
    }

    @Override
    public boolean add(E o) {
        boolean added = super.add(o);
        while (added && size() > limit) {
           super.remove();
        }
        return added;
    }
}

Does Spring Data JPA have any way to count entites using method name resolving?

Thanks you all! Now it's work. DATAJPA-231

It will be nice if was possible to create count…By… methods just like find…By ones. Example:

public interface UserRepository extends JpaRepository<User, Long> {

   public Long /*or BigInteger */ countByActiveTrue();
}

Bootstrap 3 Navbar with Logo

My approach is to include FOUR different images of different sizes for phones, tablet, desktop, large desktop but only show ONE using bootstrap's responsive utility classes, as follow:

<!--<a class="navbar-brand" href="<?php echo home_url(); ?>/"><?php bloginfo('name'); ?></a>-->

        <a class="navbar-brand visible-xs" href="<?php echo home_url(); ?>/"><img src="/assets/logo-phone.png" alt="<?php bloginfo('name'); ?> Logo" /></a>
        <a class="navbar-brand visible-sm" href="<?php echo home_url(); ?>/"><img src="/assets/logo-tablet.png" alt="<?php bloginfo('name'); ?> Logo" /></a>
        <a class="navbar-brand visible-md" href="<?php echo home_url(); ?>/"><img src="/assets/logo-desktop.png" alt="<?php bloginfo('name'); ?> Logo" /></a>
        <a class="navbar-brand visible-lg" href="<?php echo home_url(); ?>/"><img src="/assets/logo-large.png" alt="<?php bloginfo('name'); ?> Logo" /></a>

Note: You can replace the commented line with the code provided. Replace the php code if you're not using wordpress.

Edit Note2: Yes, this adds requests to your server when loading the page which might slow down a bit but if you use a background css sprite technique, chances are the logo doesn't get printed when printing a page and the code above should get better SEO.

Network tools that simulate slow network connection

If you use Apache, you can use mod_bandwith.

See here for configuration parameters.

ReactJS - Does render get called any time "setState" is called?

Another reason for "lost update" can be the next:

  • If the static getDerivedStateFromProps is defined then it is rerun in every update process according to official documentation https://reactjs.org/docs/react-component.html#updating.
  • so if that state value comes from props at the beginning it is overwrite in every update.

If it is the problem then U can avoid setting the state during update, you should check the state parameter value like this

static getDerivedStateFromProps(props: TimeCorrectionProps, state: TimeCorrectionState): TimeCorrectionState {
   return state ? state : {disable: false, timeCorrection: props.timeCorrection};
}

Another solution is add a initialized property to state, and set it up in the first time (if the state is initialized to non null value.)

How do I rotate text in css?

I guess this is what you are looking for?

Added an example:

The html:

<div class="example-date">
  <span class="day">31</span> 
  <span class="month">July</span> 
  <span class="year">2009</span>
</div>

The css:

.year
{
    display:block;
    -webkit-transform: rotate(-90deg); 
    -moz-transform: rotate(-90deg); 
    filter: progid:DXImageTransform.Microsoft.BasicImage(rotation=3); //For IE support
}

Alle examples are from the mentioned site.

Convert IQueryable<> type object to List<T> type?

Then just Select:

var list = source.Select(s=>new { ID = s.ID, Name = s.Name }).ToList();

(edit) Actually - the names could be inferred in this case, so you could use:

var list = source.Select(s=>new { s.ID, s.Name }).ToList();

which saves a few electrons...

Specified cast is not valid?

From your comment:

this line DateTime Date = reader.GetDateTime(0); was throwing the exception

The first column is not a valid DateTime. Most likely, you have multiple columns in your table, and you're retrieving them all by running this query:

SELECT * from INFO

Replace it with a query that retrieves only the two columns you're interested in:

SELECT YOUR_DATE_COLUMN, YOUR_TIME_COLUMN from INFO

Then try reading the values again:

var Date = reader.GetDateTime(0);
var Time = reader.GetTimeSpan(1);  // equivalent to time(7) from your database

Or:

var Date = Convert.ToDateTime(reader["YOUR_DATE_COLUMN"]);
var Time = (TimeSpan)reader["YOUR_TIME_COLUMN"];

What is an abstract class in PHP?

Abstract Class
1. Contains an abstract method
2. Cannot be directly initialized
3. Cannot create an object of abstract class
4. Only used for inheritance purposes

Abstract Method
1. Cannot contain a body
2. Cannot be defined as private
3. Child classes must define the methods declared in abstract class

Example Code:

abstract class A {
    public function test1() {
        echo 'Hello World';
    }
    abstract protected function f1();
    abstract public function f2();
    protected function test2(){
        echo 'Hello World test';
    }
}

class B extends A {
    public $a = 'India';
    public function f1() {
        echo "F1 Method Call";
    }
    public function f2() {
        echo "F2 Method Call";
    }
}

$b = new B();
echo $b->test1() . "<br/>";
echo $b->a . "<br/>";
echo $b->test2() . "<br/>";
echo $b->f1() . "<br/>";
echo $b->f2() . "<br/>";

Output:

Hello World
India
Hello World test
F1 Method Call
F2 Method Call

How to JSON decode array elements in JavaScript?

JSON decoding in JavaScript is simply an eval() if you trust the string or the more safe code you can find on http://json.org if you don't.

You will then have a JavaScript datastructure that you can traverse for the data you need.

Get last n lines of a file, similar to tail

it's so simple:

def tail(fname,nl):
with open(fname) as f:
    data=f.readlines() #readlines return a list
    print(''.join(data[-nl:]))

Catch an exception thrown by an async void method

Its also important to note that you will lose the chronological stack trace of the exception if you you have a void return type on an async method. I would recommend returning Task as follows. Going to make debugging a whole lot easier.

public async Task DoFoo()
    {
        try
        {
            return await Foo();
        }
        catch (ProtocolException ex)
        {
            /* Exception with chronological stack trace */     
        }
    }

Fetching data from MySQL database using PHP, Displaying it in a form for editing

<form action="Delegate_update.php" method="post">
Name
<input type="text" name= "Name" value= "<?php echo $row['Name']; ?> "size=10>
Username
<input type="text" name= "Username" value= "<?php echo $row['Username']; ?> "size=10>
Password
<input type="text" name= "Password" value= "<?php echo $row['Password']; ?>" size=17>
<input type="submit" name= "submit" value="Update">
</form>

You didnt closed your opening Form in the first place, plus your code is very very messy. I wont go into the "use pdo or mysqli statements, instead of mysql" thats for you to find out on yourself. Also you have a php tag open and close below it, not sure what is needed there. Something else is that your code refers to an external page, which you didnt post, so if something isnt working there, might be handy to post it too.

Please also note that you had spaces between your $row array variables in the form. You have to link those up together by removing the space (see edited section from me). PHP isn't forgiving when it comes to those mistakes.

Then your HTML. I took the liberty to correct that too

<html>
    <head>
        <title> Delegate edit form</title>
    </head>

    <body>
          <p>Delegate update form</p>
<?php
$usernm="root";
$passwd="";
$host="localhost";
$database="swift";

mysql_connect($host,$usernm,$passwd); 
mysql_select_db($database);

$sql = "SELECT * FROM usermaster WHERE User_name='".$Username."'"; // Please look at this too.
$result = mysql_query($sql) or die (mysql_error()); // dont put spaces in between it, else your code wont recognize it the query that needs to be executed
while ($row = mysql_fetch_array($result)){     // here too, you put a space between it
    $Name=$row['Name'];
    $Username=$row['User_name'];
    $Password=$row['User_password'];
    }
?>

Also, try to be specific. "It doesnt work" doesnt help us much, a specific error type is commonly helpful, plus any indication what the code should do (well, it was kinda obvious here, since its a login/register edit here, but for larger chunks of code it should always be explained)

Anyway, welcome to Stack Overflow

'Best' practice for restful POST response

Returning the whole object on an update would not seem very relevant, but I can hardly see why returning the whole object when it is created would be a bad practice in a normal use case. This would be useful at least to get the ID easily and to get the timestamps when relevant. This is actually the default behavior got when scaffolding with Rails.

I really do not see any advantage to returning only the ID and doing a GET request after, to get the data you could have got with your initial POST.

Anyway as long as your API is consistent I think that you should choose the pattern that fits your needs the best. There is not any correct way of how to build a REST API, imo.

How to do a deep comparison between 2 objects with lodash?

This is my solution to the problem

const _ = require('lodash');

var objects = [{ 'x': 1, 'y': 2, 'z':3, a:{b:1, c:2, d:{n:0}}, p:[1, 2, 3]  }, { 'x': 2, 'y': 1, z:3, a:{b:2, c:2,d:{n:1}}, p:[1,3], m:3  }];

const diffFn=(a,b, path='')=>_.reduce(a, function(result, value, key) {

    if(_.isObjectLike(value)){
      if(_.isEqual(value, b[key])){
        return result;
      }else{

return result.concat(diffFn(value, b[key], path?(`${path}.${key}`):key))
      }
    }else{
return _.isEqual(value, b[key]) ?
        result : result.concat(path?(`${path}.${key}`):key);
    }
    
}, []);

const diffKeys1=diffFn(objects[0], objects[1])
const diffKeys2=diffFn(objects[1], objects[0])
const diffKeys=_.union(diffKeys1, diffKeys2)
const res={};

_.forEach(diffKeys, (key)=>_.assign(res, {[key]:{ old: _.get(objects[0], key), new:_.get(objects[1], key)} }))

res
/*
Returns
{
  x: { old: 1, new: 2 },
  y: { old: 2, new: 1 },
  'a.b': { old: 1, new: 2 },
  'a.d.n': { old: 0, new: 1 },
  'p.1': { old: 2, new: 3 },
  'p.2': { old: 3, new: undefined },
  m: { old: undefined, new: 3 }
}
*/

Xcode stops working after set "xcode-select -switch"

You should be pointing it towards the Developer directory, not the Xcode application bundle. Run this:

sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer

With recent versions of Xcode, you can go to Xcode ? Preferences… ? Locations and pick one of the options for Command Line Tools to set the location.

What Does This Mean in PHP -> or =>

->

calls/sets object variables. Ex:

$obj = new StdClass;
$obj->foo = 'bar';
var_dump($obj);

=> Sets key/value pairs for arrays. Ex:

$array = array(
    'foo' => 'bar'
);
var_dump($array);

How to reset Jenkins security settings from the command line?

\.jenkins\secrets\initialAdminPassword

Copy the password from the initialAdminPassword file and paste it into the Jenkins.

jquery drop down menu closing by clicking outside

You can tell any click that bubbles all the way up the DOM to hide the dropdown, and any click that makes it to the parent of the dropdown to stop bubbling.

/* Anything that gets to the document
   will hide the dropdown */
$(document).click(function(){
  $("#dropdown").hide();
});

/* Clicks within the dropdown won't make
   it past the dropdown itself */
$("#dropdown").click(function(e){
  e.stopPropagation();
});

Demo: http://jsbin.com/umubad/2/edit

Simulating ENTER keypress in bash script

echo -ne '\n' | <yourfinecommandhere>

or taking advantage of the implicit newline that echo generates (thanks Marcin)

echo | <yourfinecommandhere>

Now we can simply use the --sk option:

--sk, --skip-keypress Don't wait for a keypress after each test

i.e. sudo rkhunter --sk --checkall

Creating a JSON Array in node js

This one helped me,

res.format({
        json:function(){
                            var responseData    = {};
                            responseData['status'] = 200;
                            responseData['outputPath']  = outputDirectoryPath;
                            responseData['sourcePath']  = url;
                            responseData['message'] = 'Scraping of requested resource initiated.';
                            responseData['logfile'] = logFileName;
                            res.json(JSON.stringify(responseData));
                        }
    });

LINUX: Link all files from one to another directory

The posted solutions will not link any hidden files. To include them, try this:

cd /usr/lib
find /mnt/usr/lib -maxdepth 1 -print "%P\n" | while read file; do ln -s "/mnt/usr/lib/$file" "$file"; done

If you should happen to want to recursively create the directories and only link files (so that if you create a file within a directory, it really is in /usr/lib not /mnt/usr/lib), you could do this:

cd /usr/lib
find /mnt/usr/lib -mindepth 1 -depth -type d -printf "%P\n" | while read dir; do mkdir -p "$dir"; done
find /mnt/usr/lib -type f -printf "%P\n" | while read file; do ln -s "/mnt/usr/lib/$file" "$file"; done

How to concatenate characters in java?

You can use the String constructor.

System.out.println(new String(new char[]{a,b,c}));

How to prevent Right Click option using jquery

If you're looking into trying to disable the downloading/saving of your images, scripts won't stop that. You would probably have better luck doing this on a server configuration level (like modifying your .htaccess for example on Apache).

Try asking this on ServerFault.

Detach (move) subdirectory into separate Git repository

This is no longer so complex you can just use the git filter-branch command on a clone of you repo to cull the subdirectories you don't want and then push to the new remote.

git filter-branch --prune-empty --subdirectory-filter <YOUR_SUBDIR_TO_KEEP> master
git push <MY_NEW_REMOTE_URL> -f .

Cannot install packages inside docker Ubuntu image

It is because there is no package cache in the image, you need to run:

apt-get update

before installing packages, and if your command is in a Dockerfile, you'll then need:

apt-get -y install curl

To suppress the standard output from a command use -qq. E.g.

apt-get -qq -y install curl

Error 5 : Access Denied when starting windows service

In my case following was not checked.

enter image description here

Cannot set property 'display' of undefined

document.getElementsByClassName('btn-pageMenu') delivers a nodeList. You should use: document.getElementsByClassName('btn-pageMenu')[0].style.display (if it's the first element from that list you want to change.

If you want to change style.display for all nodes loop through the list:

var elems = document.getElementsByClassName('btn-pageMenu');
for (var i=0;i<elems.length;i+=1){
  elems[i].style.display = 'block';
}

to be complete: if you use jquery it is as simple as:

?$('.btn-pageMenu').css('display'???????????????????????????,'block');??????

Bat file to run a .exe at the command prompt

If you want to be real smart, at the command line type:

echo svcutil.exe /language:cs /out:generatedProxy.cs /config:app.config http://localhost:8000/ServiceModelSamples/service >CreateService.cmd

Then you have CreateService.cmd that you can run whenever you want (.cmd is just another extension for .bat files)

How do I set up HttpContent for my HttpClient PostAsync second parameter?

This is answered in some of the answers to Can't find how to use HttpContent as well as in this blog post.

In summary, you can't directly set up an instance of HttpContent because it is an abstract class. You need to use one the classes derived from it depending on your need. Most likely StringContent, which lets you set the string value of the response, the encoding, and the media type in the constructor. See: http://msdn.microsoft.com/en-us/library/system.net.http.stringcontent.aspx

What is the use of printStackTrace() method in Java?

printStackTrace() prints the locations where the exception occurred in the source code, thus allowing the author who wrote the program to see what went wrong. But since it shows problems in the source code, the user(s) who may or may not have any coding experience may not be able to understand what went wrong, so if the program allows the user to send error messages to the authors, the users may not be able to give good data on what went wrong.

You should consider the Logger.getLogger() method, it offers a better exception handling (logging) facility, and besides printStackTrace() without arguments is considered to be obsolete and should ONLY be used for debugging purposes, not for user display.

src absolute path problem

<img src="file://C:/wamp/www/site/img/mypicture.jpg"/>

C# Convert List<string> to Dictionary<string, string>

Use this:

var dict = list.ToDictionary(x => x);

See MSDN for more info.

As Pranay points out in the comments, this will fail if an item exists in the list multiple times.
Depending on your specific requirements, you can either use var dict = list.Distinct().ToDictionary(x => x); to get a dictionary of distinct items or you can use ToLookup instead:

var dict = list.ToLookup(x => x);

This will return an ILookup<string, string> which is essentially the same as IDictionary<string, IEnumerable<string>>, so you will have a list of distinct keys with each string instance under it.

Cloud Firestore collection count

I agree with @Matthew, it will cost a lot if you perform such query.

[ADVICE FOR DEVELOPERS BEFORE STARTING THEIR PROJECTS]

Since we have foreseen this situation at the beginning, we can actually make a collection namely counters with a document to store all the counters in a field with type number.

For example:

For each CRUD operation on the collection, update the counter document:

  1. When you create a new collection/subcollection: (+1 in the counter) [1 write operation]
  2. When you delete a collection/subcollection: (-1 in the counter) [1 write operation]
  3. When you update an existing collection/subcollection, do nothing on the counter document: (0)
  4. When you read an existing collection/subcollection, do nothing on the counter document: (0)

Next time, when you want to get the number of collection, you just need to query/point to the document field. [1 read operation]

In addition, you can store the collections name in an array, but this will be tricky, the condition of array in firebase is shown as below:

// we send this
['a', 'b', 'c', 'd', 'e']
// Firebase stores this
{0: 'a', 1: 'b', 2: 'c', 3: 'd', 4: 'e'}

// since the keys are numeric and sequential,
// if we query the data, we get this
['a', 'b', 'c', 'd', 'e']

// however, if we then delete a, b, and d,
// they are no longer mostly sequential, so
// we do not get back an array
{2: 'c', 4: 'e'}

So, if you are not going to delete the collection , you can actually use array to store list of collections name instead of querying all the collection every time.

Hope it helps!

Display SQL query results in php

You cannot directly see the query result using mysql_query its only fires the query in mysql nothing else.

For getting the result you have to add a lil things in your script like

require_once('db.php');  
 $sql="SELECT * FROM  modul1open WHERE idM1O>=(SELECT FLOOR( MAX( idM1O ) * RAND( ) )  FROM  modul1open) ORDER BY idM1O LIMIT 1";

 $result = mysql_query($sql);
 //echo [$result];
while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
    print_r($row);
}

This will give you result;

Nexus 7 (2013) and Win 7 64 - cannot install USB driver despite checking many forums and online resources

The universal adb driver installer worked for me. I went from an HTC to a Samsung to a LG Nexus. The drivers are all over the place for me.

http://adbdriver.com/

How can I divide two integers to get a double?

Complementing the @NoahD's answer

To have a greater precision you can cast to decimal:

(decimal)100/863
//0.1158748551564310544611819235

Or:

Decimal.Divide(100, 863)
//0.1158748551564310544611819235

Double are represented allocating 64 bits while decimal uses 128

(double)100/863
//0.11587485515643106

In depth explanation of "precision"

For more details about the floating point representation in binary and its precision take a look at this article from Jon Skeet where he talks about floats and doubles and this one where he talks about decimals.

Detect application heap size in Android

Runtime rt = Runtime.getRuntime();
rt.maxMemory()

value is b

ActivityManager am = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
am.getMemoryClass()

value is MB

ITextSharp insert text to an existing pdf

Here is a method that uses stamper and absolute coordinates showed in the different PDF clients (Adobe, FoxIt and etc. )

public static void AddTextToPdf(string inputPdfPath, string outputPdfPath, string textToAdd, System.Drawing.Point point)
    {
        //variables
        string pathin = inputPdfPath;
        string pathout = outputPdfPath;

        //create PdfReader object to read from the existing document
        using (PdfReader reader = new PdfReader(pathin))
        //create PdfStamper object to write to get the pages from reader 
        using (PdfStamper stamper = new PdfStamper(reader, new FileStream(pathout, FileMode.Create)))
        {
            //select two pages from the original document
            reader.SelectPages("1-2");

            //gettins the page size in order to substract from the iTextSharp coordinates
            var pageSize = reader.GetPageSize(1);

            // PdfContentByte from stamper to add content to the pages over the original content
            PdfContentByte pbover = stamper.GetOverContent(1);

            //add content to the page using ColumnText
            Font font = new Font();
            font.Size = 45;

            //setting up the X and Y coordinates of the document
            int x = point.X;
            int y = point.Y;

            y = (int) (pageSize.Height - y);

            ColumnText.ShowTextAligned(pbover, Element.ALIGN_CENTER, new Phrase(textToAdd, font), x, y, 0);
        }
    }

Example: Communication between Activity and Service using Messaging

Seems to me you could've saved some memory by declaring your activity with "implements Handler.Callback"

Creating a batch file, for simple javac and java command execution

hey I think that you just copy your compiled class files and copy the jre folder and make the following as the content of the batch file and save all together any windows machine and just double click

@echo
setpath d:\jre
d:
cd myprogfolder
java myprogram

Why isn't sizeof for a struct equal to the sum of sizeof of each member?

This is because of padding added to satisfy alignment constraints. Data structure alignment impacts both performance and correctness of programs:

  • Mis-aligned access might be a hard error (often SIGBUS).
  • Mis-aligned access might be a soft error.
    • Either corrected in hardware, for a modest performance-degradation.
    • Or corrected by emulation in software, for a severe performance-degradation.
    • In addition, atomicity and other concurrency-guarantees might be broken, leading to subtle errors.

Here's an example using typical settings for an x86 processor (all used 32 and 64 bit modes):

struct X
{
    short s; /* 2 bytes */
             /* 2 padding bytes */
    int   i; /* 4 bytes */
    char  c; /* 1 byte */
             /* 3 padding bytes */
};

struct Y
{
    int   i; /* 4 bytes */
    char  c; /* 1 byte */
             /* 1 padding byte */
    short s; /* 2 bytes */
};

struct Z
{
    int   i; /* 4 bytes */
    short s; /* 2 bytes */
    char  c; /* 1 byte */
             /* 1 padding byte */
};

const int sizeX = sizeof(struct X); /* = 12 */
const int sizeY = sizeof(struct Y); /* = 8 */
const int sizeZ = sizeof(struct Z); /* = 8 */

One can minimize the size of structures by sorting members by alignment (sorting by size suffices for that in basic types) (like structure Z in the example above).

IMPORTANT NOTE: Both the C and C++ standards state that structure alignment is implementation-defined. Therefore each compiler may choose to align data differently, resulting in different and incompatible data layouts. For this reason, when dealing with libraries that will be used by different compilers, it is important to understand how the compilers align data. Some compilers have command-line settings and/or special #pragma statements to change the structure alignment settings.

Border color on default input style

You can use jquery for this by utilizing addClass() method

CSS

 .defaultInput
    {
     width: 100px;
     height:25px;
     padding: 5px;
    }

.error
{
 border:1px solid red;
}

<input type="text" class="defaultInput"/>

Jquery Code

$(document).ready({
  $('.defaultInput').focus(function(){
       $(this).addClass('error');
  });
});

Update: You can remove that error class using

$('.defaultInput').removeClass('error');

It won't remove that default style. It will remove .error class only

Plotting of 1-dimensional Gaussian distribution function

You are missing a parantheses in the denominator of your gaussian() function. As it is right now you divide by 2 and multiply with the variance (sig^2). But that is not true and as you can see of your plots the greater variance the more narrow the gaussian is - which is wrong, it should be opposit.

So just change the gaussian() function to:

def gaussian(x, mu, sig):
    return np.exp(-np.power(x - mu, 2.) / (2 * np.power(sig, 2.)))

What is the difference between printf() and puts() in C?

(This is pointed out in a comment by Zan Lynx, but I think it deserves an aswer - given that the accepted answer doesn't mention it).

The essential difference between puts(mystr); and printf(mystr); is that in the latter the argument is interpreted as a formatting string. The result will be often the same (except for the added newline) if the string doesn't contain any control characters (%) but if you cannot rely on that (if mystr is a variable instead of a literal) you should not use it.

So, it's generally dangerous -and conceptually wrong- to pass a dynamic string as single argument of printf:

  char * myMessage;
  // ... myMessage gets assigned at runtime, unpredictable content
  printf(myMessage);  // <--- WRONG! (what if myMessage contains a '%' char?) 
  puts(myMessage);    // ok
  printf("%s\n",myMessage); // ok, equivalent to the previous, perhaps less efficient

The same applies to fputs vs fprintf (but fputs doesn't add the newline).

Unable to connect PostgreSQL to remote database using pgAdmin

In linux terminal try this:

  • sudo service postgresql start : to start the server
  • sudo service postgresql stop : to stop thee server
  • sudo service postgresql status : to check server status

getting "No column was specified for column 2 of 'd'" in sql server cte?

You just need to provide an alias for your aggregate columns in the CTE

d as (SELECT 
   duration, 
   sum(totalitems) as sumtotalitems
FROM 
   [DrySoftBranch].[dbo].[mnthItemWiseTotalQty] ('1') AS BkdQty
group by duration
)

Difference between <context:annotation-config> and <context:component-scan>

<context:annotation-config> is used to activate annotations in beans already registered in the application context (no matter if they were defined with XML or by package scanning).

<context:component-scan> can also do what <context:annotation-config> does but <context:component-scan> also scans packages to find and register beans within the application context.

I'll use some examples to show the differences/similarities.

Lets start with a basic setup of three beans of type A, B and C, with B and C being injected into A.

package com.xxx;
public class B {
  public B() {
    System.out.println("creating bean B: " + this);
  }
}

package com.xxx;
public class C {
  public C() {
    System.out.println("creating bean C: " + this);
  }
}

package com.yyy;
import com.xxx.B;
import com.xxx.C;
public class A { 
  private B bbb;
  private C ccc;
  public A() {
    System.out.println("creating bean A: " + this);
  }
  public void setBbb(B bbb) {
    System.out.println("setting A.bbb with " + bbb);
    this.bbb = bbb;
  }
  public void setCcc(C ccc) {
    System.out.println("setting A.ccc with " + ccc);
    this.ccc = ccc; 
  }
}

With the following XML configuration :

<bean id="bBean" class="com.xxx.B" />
<bean id="cBean" class="com.xxx.C" />
<bean id="aBean" class="com.yyy.A">
  <property name="bbb" ref="bBean" />
  <property name="ccc" ref="cBean" />
</bean>

Loading the context produces the following output:

creating bean B: com.xxx.B@c2ff5
creating bean C: com.xxx.C@1e8a1f6
creating bean A: com.yyy.A@1e152c5
setting A.bbb with com.xxx.B@c2ff5
setting A.ccc with com.xxx.C@1e8a1f6

OK, this is the expected output. But this is "old style" Spring. Now we have annotations so lets use those to simplify the XML.

First, lets autowire the bbb and ccc properties on bean A like so:

package com.yyy;
import org.springframework.beans.factory.annotation.Autowired;
import com.xxx.B;
import com.xxx.C;
public class A { 
  private B bbb;
  private C ccc;
  public A() {
    System.out.println("creating bean A: " + this);
  }
  @Autowired
  public void setBbb(B bbb) {
    System.out.println("setting A.bbb with " + bbb);
    this.bbb = bbb;
  }
  @Autowired
  public void setCcc(C ccc) {
    System.out.println("setting A.ccc with " + ccc);
    this.ccc = ccc;
  }
}

This allows me to remove the following rows from the XML:

<property name="bbb" ref="bBean" />
<property name="ccc" ref="cBean" />

My XML is now simplified to this:

<bean id="bBean" class="com.xxx.B" />
<bean id="cBean" class="com.xxx.C" />
<bean id="aBean" class="com.yyy.A" />

When I load the context I get the following output:

creating bean B: com.xxx.B@5e5a50
creating bean C: com.xxx.C@54a328
creating bean A: com.yyy.A@a3d4cf

OK, this is wrong! What happened? Why aren't my properties autowired?

Well, annotations are a nice feature but by themselves they do nothing whatsoever. They just annotate stuff. You need a processing tool to find the annotations and do something with them.

<context:annotation-config> to the rescue. This activates the actions for the annotations that it finds on the beans defined in the same application context where itself is defined.

If I change my XML to this:

<context:annotation-config />
<bean id="bBean" class="com.xxx.B" />
<bean id="cBean" class="com.xxx.C" />
<bean id="aBean" class="com.yyy.A" />

when I load the application context I get the proper result:

creating bean B: com.xxx.B@15663a2
creating bean C: com.xxx.C@cd5f8b
creating bean A: com.yyy.A@157aa53
setting A.bbb with com.xxx.B@15663a2
setting A.ccc with com.xxx.C@cd5f8b

OK, this is nice, but I've removed two rows from the XML and added one. That's not a very big difference. The idea with annotations is that it's supposed to remove the XML.

So let's remove the XML definitions and replace them all with annotations:

package com.xxx;
import org.springframework.stereotype.Component;
@Component
public class B {
  public B() {
    System.out.println("creating bean B: " + this);
  }
}

package com.xxx;
import org.springframework.stereotype.Component;
@Component
public class C {
  public C() {
    System.out.println("creating bean C: " + this);
  }
}

package com.yyy;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import com.xxx.B;
import com.xxx.C;
@Component
public class A { 
  private B bbb;
  private C ccc;
  public A() {
    System.out.println("creating bean A: " + this);
  }
  @Autowired
  public void setBbb(B bbb) {
    System.out.println("setting A.bbb with " + bbb);
    this.bbb = bbb;
  }
  @Autowired
  public void setCcc(C ccc) {
    System.out.println("setting A.ccc with " + ccc);
    this.ccc = ccc;
  }
}

While in the XML we only keep this:

<context:annotation-config />

We load the context and the result is... Nothing. No beans are created, no beans are autowired. Nothing!

That's because, as I said in the first paragraph, the <context:annotation-config /> only works on beans registered within the application context. Because I removed the XML configuration for the three beans there is no bean created and <context:annotation-config /> has no "targets" to work on.

But that won't be a problem for <context:component-scan> which can scan a package for "targets" to work on. Let's change the content of the XML config into the following entry:

<context:component-scan base-package="com.xxx" />

When I load the context I get the following output:

creating bean B: com.xxx.B@1be0f0a
creating bean C: com.xxx.C@80d1ff

Hmmmm... something is missing. Why?

If you look closelly at the classes, class A has package com.yyy but I've specified in the <context:component-scan> to use package com.xxx so this completely missed my A class and only picked up B and C which are on the com.xxx package.

To fix this, I add this other package also:

<context:component-scan base-package="com.xxx,com.yyy" />

and now we get the expected result:

creating bean B: com.xxx.B@cd5f8b
creating bean C: com.xxx.C@15ac3c9
creating bean A: com.yyy.A@ec4a87
setting A.bbb with com.xxx.B@cd5f8b
setting A.ccc with com.xxx.C@15ac3c9

And that's it! Now you don't have XML definitions anymore, you have annotations.

As a final example, keeping the annotated classes A, B and C and adding the following to the XML, what will we get after loading the context?

<context:component-scan base-package="com.xxx" />
<bean id="aBean" class="com.yyy.A" />

We still get the correct result:

creating bean B: com.xxx.B@157aa53
creating bean C: com.xxx.C@ec4a87
creating bean A: com.yyy.A@1d64c37
setting A.bbb with com.xxx.B@157aa53
setting A.ccc with com.xxx.C@ec4a87

Even if the bean for class A isn't obtained by scanning, the processing tools are still applied by <context:component-scan> on all beans registered in the application context, even for A which was manually registered in the XML.

But what if we have the following XML, will we get duplicated beans because we've specified both <context:annotation-config /> and <context:component-scan>?

<context:annotation-config />
<context:component-scan base-package="com.xxx" />
<bean id="aBean" class="com.yyy.A" />

No, no duplications, We again get the expected result:

creating bean B: com.xxx.B@157aa53
creating bean C: com.xxx.C@ec4a87
creating bean A: com.yyy.A@1d64c37
setting A.bbb with com.xxx.B@157aa53
setting A.ccc with com.xxx.C@ec4a87

That's because both tags register the same processing tools (<context:annotation-config /> can be omitted if <context:component-scan> is specified) but Spring takes care of running them only once.

Even if you register the processing tools yourself multiple times, Spring will still make sure they do their magic only once; this XML:

<context:annotation-config />
<context:component-scan base-package="com.xxx" />
<bean id="aBean" class="com.yyy.A" />
<bean id="bla" class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor" />
<bean id="bla1" class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor" />
<bean id="bla2" class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor" />
<bean id="bla3" class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor" />

will still generate the following result:

creating bean B: com.xxx.B@157aa53
creating bean C: com.xxx.C@ec4a87
creating bean A: com.yyy.A@25d2b2
setting A.bbb with com.xxx.B@157aa53
setting A.ccc with com.xxx.C@ec4a87

OK, that about raps it up.

I hope this information along with the responses from @Tomasz Nurkiewicz and @Sean Patrick Floyd are all you need to understand how <context:annotation-config> and <context:component-scan> work.

ExpressionChangedAfterItHasBeenCheckedError Explained

Tried most of the solutions suggested above. Only this worked for me in this scenario. I was using *ngIf to toggle angular material's indeterminate progressive bar based on api calls and it was throwing ExpressionChangedAfterItHasBeenCheckedError.

In the component in question:

constructor(
    private ngZone: NgZone,
    private changeDetectorRef: ChangeDetectorRef,
) {}

ngOnInit() {
    this.ngZone.runOutsideAngular(() => {
        this.appService.appLoader$.subscribe(value => {
            this.loading = value;
            this.changeDetectorRef.detectChanges();
        });
    });
}

The trick is to bypass angular component's change detection using ngzone.

PS: Not sure if this is an elegant solution but using AfterContentChecked and AfterViewChecked lifecycle hook is bound to raise performance issues as your application gets bigger as it is triggered numerous times.

DLL load failed error when importing cv2

After spending too much time on this issue and trying out all different answers, here is what found:

  • The accepted answer by @thewaywewere is no longer applicable. I think this was applicable when opencv-python module still wasn't available.

  • This is indeed a bug in Anaconda 4.2 because they forgot to ship python3.dll. They have fixed this in next releases but unfortunately 4.2 is the last release with Python 3.5 as default. If you are stuck with Python 3.5 (for example VS2015 is only aware of versions up to 3.5) then you must manually download python3.dll as described in answer by @Ramesh-X.

  • If you can move on to Python 3.6 (which at present bit difficult if you are using OpenCV and VS2015) then just install latest Anaconda version and you don't have to deal with any of these.

CMake error at CMakeLists.txt:30 (project): No CMAKE_C_COMPILER could be found

I get exactly the reported error if ccache is enabled, when using CMake's Xcode generator. Disabling ccache fixed the problem for me. Below I present a fix/check that works for MacOS, but should work similarly on other platforms.

Apparently, it is possible to use CMake's Xcode generator (and others) also in combination with ccache, as is described here. But I never tried it out myself.

# 1) To check if ccache is enabled:
echo $CC
echo $CXX
# This prints something like the following: 
#     ccache clang -Qunused-arguments -fcolor-diagnostics. 
# CC or CXX are typically set in the `.bashrc` or `.zshrc` file.

# 2) To disable ccache, use the following:
CC=clang
CXX=clang++

# 3) Then regenerate the cmake project
cmake -G Xcode <path/to/CMakeLists.txt>

Trying to get property of non-object MySQLi result

$sql = "SELECT * FROM table";
$result = $conn->query($sql);

if (!$result) {
    trigger_error('Invalid query: ' . $conn->error);
}

check the error with mysqli_error() function

probably your query has some faults.

How do I do a HTTP GET in Java?

Technically you could do it with a straight TCP socket. I wouldn't recommend it however. I would highly recommend you use Apache HttpClient instead. In its simplest form:

GetMethod get = new GetMethod("http://httpcomponents.apache.org");
// execute method and handle any error responses.
...
InputStream in = get.getResponseBodyAsStream();
// Process the data from the input stream.
get.releaseConnection();

and here is a more complete example.

How to do SVN Update on my project using the command line

I think I got it. It's:

"SVN Client Path"  /command:update / path:"My folder path"

Convert HttpPostedFileBase to byte[]

As Darin says, you can read from the input stream - but I'd avoid relying on all the data being available in a single go. If you're using .NET 4 this is simple:

MemoryStream target = new MemoryStream();
model.File.InputStream.CopyTo(target);
byte[] data = target.ToArray();

It's easy enough to write the equivalent of CopyTo in .NET 3.5 if you want. The important part is that you read from HttpPostedFileBase.InputStream.

For efficient purposes you could check whether the stream returned is already a MemoryStream:

byte[] data;
using (Stream inputStream = model.File.InputStream)
{
    MemoryStream memoryStream = inputStream as MemoryStream;
    if (memoryStream == null)
    {
        memoryStream = new MemoryStream();
        inputStream.CopyTo(memoryStream);
    }
    data = memoryStream.ToArray();
}

How to create a library project in Android Studio and an application project that uses the library project

I wonder why there is no example of stand alone jar project.

In eclipse, we just check "Is Library" box in project setting dialog.
In Android studio, I followed this steps and got a jar file.

  1. Create a project.

  2. open file in the left project menu.(app/build.gradle): Gradle Scripts > build.gradle(Module: XXX)

  3. change one line: apply plugin: 'com.android.application' -> 'apply plugin: com.android.library'

  4. remove applicationId in the file: applicationId "com.mycompany.testproject"

  5. build project: Build > Rebuild Project

  6. then you can get aar file: app > build > outputs > aar folder

  7. change aar file extension name into zip

  8. unzip, and you can see classes.jar in the folder. rename and use it!

Anyway, I don't know why google makes jar creation so troublesome in android studio.

c++ parse int from string

  • In C++11, use std::stoi as:

     std::string s = "10";
     int i = std::stoi(s);
    

    Note that std::stoi will throw exception of type std::invalid_argument if the conversion cannot be performed, or std::out_of_range if the conversion results in overflow(i.e when the string value is too big for int type). You can use std::stol or std:stoll though in case int seems too small for the input string.

  • In C++03/98, any of the following can be used:

     std::string s = "10";
     int i;
    
     //approach one
     std::istringstream(s) >> i; //i is 10 after this
    
     //approach two
     sscanf(s.c_str(), "%d", &i); //i is 10 after this
    

Note that the above two approaches would fail for input s = "10jh". They will return 10 instead of notifying error. So the safe and robust approach is to write your own function that parses the input string, and verify each character to check if it is digit or not, and then work accordingly. Here is one robust implemtation (untested though):

int to_int(char const *s)
{
     if ( s == NULL || *s == '\0' )
        throw std::invalid_argument("null or empty string argument");

     bool negate = (s[0] == '-');
     if ( *s == '+' || *s == '-' ) 
         ++s;

     if ( *s == '\0')
        throw std::invalid_argument("sign character only.");

     int result = 0;
     while(*s)
     {
          if ( *s < '0' || *s > '9' )
            throw std::invalid_argument("invalid input string");
          result = result * 10  - (*s - '0');  //assume negative number
          ++s;
     }
     return negate ? result : -result; //-result is positive!
} 

This solution is slightly modified version of my another solution.

How to prevent null values inside a Map and null fields inside a bean from getting serialized through Jackson

If it's reasonable to alter the original Map data structure to be serialized to better represent the actual value wanted to be serialized, that's probably a decent approach, which would possibly reduce the amount of Jackson configuration necessary. For example, just remove the null key entries, if possible, before calling Jackson. That said...


To suppress serializing Map entries with null values:

Before Jackson 2.9

you can still make use of WRITE_NULL_MAP_VALUES, but note that it's moved to SerializationFeature:

mapper.configure(SerializationFeature.WRITE_NULL_MAP_VALUES, false);

Since Jackson 2.9

The WRITE_NULL_MAP_VALUES is deprecated, you can use the below equivalent:

mapper.setDefaultPropertyInclusion(
   JsonInclude.Value.construct(Include.ALWAYS, Include.NON_NULL))

To suppress serializing properties with null values, you can configure the ObjectMapper directly, or make use of the @JsonInclude annotation:

mapper.setSerializationInclusion(Include.NON_NULL);

or:

@JsonInclude(Include.NON_NULL)
class Foo
{
  public String bar;

  Foo(String bar)
  {
    this.bar = bar;
  }
}

To handle null Map keys, some custom serialization is necessary, as best I understand.

A simple approach to serialize null keys as empty strings (including complete examples of the two previously mentioned configurations):

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import com.fasterxml.jackson.annotation.JsonInclude.Include;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.SerializerProvider;

public class JacksonFoo
{
  public static void main(String[] args) throws Exception
  {
    Map<String, Foo> foos = new HashMap<String, Foo>();
    foos.put("foo1", new Foo("foo1"));
    foos.put("foo2", new Foo(null));
    foos.put("foo3", null);
    foos.put(null, new Foo("foo4"));

    // System.out.println(new ObjectMapper().writeValueAsString(foos));
    // Exception: Null key for a Map not allowed in JSON (use a converting NullKeySerializer?)

    ObjectMapper mapper = new ObjectMapper();
    mapper.configure(SerializationFeature.WRITE_NULL_MAP_VALUES, false);
    mapper.setSerializationInclusion(Include.NON_NULL);
    mapper.getSerializerProvider().setNullKeySerializer(new MyNullKeySerializer());
    System.out.println(mapper.writeValueAsString(foos));
    // output: 
    // {"":{"bar":"foo4"},"foo2":{},"foo1":{"bar":"foo1"}}
  }
}

class MyNullKeySerializer extends JsonSerializer<Object>
{
  @Override
  public void serialize(Object nullKey, JsonGenerator jsonGenerator, SerializerProvider unused) 
      throws IOException, JsonProcessingException
  {
    jsonGenerator.writeFieldName("");
  }
}

class Foo
{
  public String bar;

  Foo(String bar)
  {
    this.bar = bar;
  }
}

To suppress serializing Map entries with null keys, further custom serialization processing would be necessary.

Run a mySQL query as a cron job?

Try creating a shell script like the one below:

#!/bin/bash

mysql --user=[username] --password=[password] --database=[db name] --execute="DELETE FROM tbl_message WHERE DATEDIFF( NOW( ) ,  timestamp ) >=7"

You can then add this to the cron

How to remove the Flutter debug banner?

There is also another way for removing the "debug" banner from the flutter app. Now after new release there is no "debugShowCheckedModeBanner: false," code line in main .dart file. So I think these methods are effective:

  1. If you are using VS Code, then install "Dart DevTools" from extensions. After installation, you can easily find "Dart DevTools" text icon at the bottom of the VS Code. When you click on that text icon, a link will be open in google chrome. From that link page, you can easily remove the banner by just tapping on the banner icon as shown in this screenshot.

NOTE:-- Dart DevTools is a dart language debugger extension in VS Code

  1. If Dart DevTools is already installed in your VS Code, then you can directly open the google chrome and open this URL = "127.0.0.1: ZZZZZ/?hide=debugger&port=XXXXX"

NOTE:-- In this link replace "XXXXX" by 5 digit port-id (on which your flutter app is running) which will vary whenever you use "flutter run" command and replace "ZZZZZ" by your global(unchangeable) 5 digit debugger-id

NOTE:-- these dart dev tools are only for "Google Chrome Browser"

Using the value in a cell as a cell reference in a formula?

Use INDIRECT()

=SUM(INDIRECT(<start cell here> & ":" & <end cell here>))

How to get the last element of an array in Ruby?

One other way, using the splat operator:

*a, last = [1, 3, 4, 5]

STDOUT:
a: [1, 3, 4]
last: 5

Enum Naming Convention - Plural

If you are trying to write straightforward, yet forbidden code like this:

    public class Person
    {
        public enum Gender
        {
            Male,
            Female
        }
        //Won't compile: auto-property has same name as enum
        public Gender Gender { get; set; }  
    }

Your options are:

  1. Ignore the MS recommendation and use a prefix or suffix on the enum name:

    public class Person
    {
        public enum GenderEnum
        {
            Male,
            Female
        }
        public GenderEnum Gender { get; set; }
    }
    
  2. Move the enum definition outside the class, preferably into another class. Here is an easy solution to the above:

    public class Characteristics
    {
        public enum Gender
        {
            Male,
            Female
        }
    }
    public class Person
    {
        public Characteristics.Gender Gender { get; set; }  
    }
    

Could not load file or assembly System.Web.Http.WebHost after published to Azure web site

If you are still looking for an answer, try checking this question thread. It helped me resolve a similar problem.

edit: The solution that helped me was to run Update-Package Microsoft.AspNet.WebApi -reinstall from the NugGet package manager, as suggested by Pathoschild. I then had to delete my .suo file and restart VS, as suggested by Sergey Osypchuk in this thread.

Reading a .txt file using Scanner class in Java

  1. Make sure the filename is correct (proper capitalisation, matching extension etc - as already suggested).

  2. Use the Class.getResource method to locate your file in the classpath - don't rely on the current directory:

    URL url = insertionSort.class.getResource("10_Random");
    
    File file = new File(url.toURI());
    
  3. Specify the absolute file path via command-line arguments:

    File file = new File(args[0]);
    

In Eclipse:

  1. Choose "Run configurations"
  2. Go to the "Arguments" tab
  3. Put your "c:/my/file/is/here/10_Random.txt.or.whatever" into the "Program arguments" section

Refreshing page on click of a button

There are several ways to reload the current page using a button or other trigger. The examples below use a button click to reload the page but you can use a text hyperlink or any trigger you like.

<input type="button" value="Reload Page" onClick="window.location.reload()">

<input type="button" value="Reload Page" onClick="history.go(0)">

<input type="button" value="Reload Page" onClick="window.location.href=window.location.href">

Is there a RegExp.escape function in JavaScript?

The functions in the other answers are overkill for escaping entire regular expressions (they may be useful for escaping parts of regular expressions that will later be concatenated into bigger regexps).

If you escape an entire regexp and are done with it, quoting the metacharacters that are either standalone (., ?, +, *, ^, $, |, \) or start something ((, [, {) is all you need:

String.prototype.regexEscape = function regexEscape() {
  return this.replace(/[.?+*^$|({[\\]/g, '\\$&');
};

And yes, it's disappointing that JavaScript doesn't have a function like this built-in.

What is phtml, and when should I use a .phtml extension rather than .php?

To give an example to what Alex said, if you're using Magento, for example, .phtml files are only to be found in the /design area as template files, and contain both HTML and PHP lines. Meanwhile the PHP files are pure code and don't have any lines of HTML in them.

How to redirect page after click on Ok button on sweet alert?

I wasn't able to do that with any swal(sweatAlert) default callback function, so I forced with jquery, got the Ok button class inspecting the element in chrome an made something like this:

<script>    
          sweetAlert({
                title:'Warning!',
                text: 'Invalid user or password!',
                type:'warning'
          },function(isConfirm){
                alert('ok');
          });
          $('.swal2-confirm').click(function(){
                window.location.href = 'index.php';
          });
</script>

The 'Ok' alert in function(isConfirm) was just a test to see if it would get into this function, if so I should be able to redirect from there, but I wasn't...

So I used jQuery to determine if the button "OK" of swal was clicked by getting it class: ".swal2-confirm' then I could redirect with success...

Hope this helps you all !

PS: I am using php echo to run the script, I din't have to leave php to run it, just use single quotes and you're done !

How to set HttpResponse timeout for Android in Java

For those saying that the answer of @kuester2000 does not work, please be aware that HTTP requests, first try to find the host IP with a DNS request and then makes the actual HTTP request to the server, so you may also need to set a timeout for the DNS request.

If your code worked without the timeout for the DNS request it's because you are able to reach a DNS server or you are hitting the Android DNS cache. By the way you can clear this cache by restarting the device.

This code extends the original answer to include a manual DNS lookup with a custom timeout:

//Our objective
String sURL = "http://www.google.com/";
int DNSTimeout = 1000;
int HTTPTimeout = 2000;

//Get the IP of the Host
URL url= null;
try {
     url = ResolveHostIP(sURL,DNSTimeout);
} catch (MalformedURLException e) {
    Log.d("INFO",e.getMessage());
}

if(url==null){
    //the DNS lookup timed out or failed.
}

//Build the request parameters
HttpParams params = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(params, HTTPTimeout);
HttpConnectionParams.setSoTimeout(params, HTTPTimeout);

DefaultHttpClient client = new DefaultHttpClient(params);

HttpResponse httpResponse;
String text;
try {
    //Execute the request (here it blocks the execution until finished or a timeout)
    httpResponse = client.execute(new HttpGet(url.toString()));
} catch (IOException e) {
    //If you hit this probably the connection timed out
    Log.d("INFO",e.getMessage());
}

//If you get here everything went OK so check response code, body or whatever

Used method:

//Run the DNS lookup manually to be able to time it out.
public static URL ResolveHostIP (String sURL, int timeout) throws MalformedURLException {
    URL url= new URL(sURL);
    //Resolve the host IP on a new thread
    DNSResolver dnsRes = new DNSResolver(url.getHost());
    Thread t = new Thread(dnsRes);
    t.start();
    //Join the thread for some time
    try {
        t.join(timeout);
    } catch (InterruptedException e) {
        Log.d("DEBUG", "DNS lookup interrupted");
        return null;
    }

    //get the IP of the host
    InetAddress inetAddr = dnsRes.get();
    if(inetAddr==null) {
        Log.d("DEBUG", "DNS timed out.");
        return null;
    }

    //rebuild the URL with the IP and return it
    Log.d("DEBUG", "DNS solved.");
    return new URL(url.getProtocol(),inetAddr.getHostAddress(),url.getPort(),url.getFile());
}   

This class is from this blog post. Go and check the remarks if you will use it.

public static class DNSResolver implements Runnable {
    private String domain;
    private InetAddress inetAddr;

    public DNSResolver(String domain) {
        this.domain = domain;
    }

    public void run() {
        try {
            InetAddress addr = InetAddress.getByName(domain);
            set(addr);
        } catch (UnknownHostException e) {
        }
    }

    public synchronized void set(InetAddress inetAddr) {
        this.inetAddr = inetAddr;
    }
    public synchronized InetAddress get() {
        return inetAddr;
    }
}

How to make an autocomplete address field with google maps api?

Below I split all the details of formatted address like City, State, Country and Zip code. 
So when you start typing your street name and select any option then street name write over street field, city name write over city field and all other fields like state, country and zip code will fill automatically. 
Using Google APIs.
------------------------------------------------
<script type="text/javascript"
src="http://maps.googleapis.com/maps/api/js?sensor=false&libraries=places"></script>
<script type="text/javascript">
google.maps.event.addDomListener(window, 'load', function() {
    var places = new google.maps.places.Autocomplete(document
            .getElementById('txtPlaces'));
    google.maps.event.addListener(places, 'place_changed', function() {
        var place = places.getPlace();
        var address = place.formatted_address;
        var  value = address.split(",");
        count=value.length;
        country=value[count-1];
        state=value[count-2];
        city=value[count-3];
        var z=state.split(" ");
        document.getElementById("selCountry").text = country;
        var i =z.length;
        document.getElementById("pstate").value = z[1];
        if(i>2)
        document.getElementById("pzcode").value = z[2];
        document.getElementById("pCity").value = city;
        var latitude = place.geometry.location.lat();
        var longitude = place.geometry.location.lng();
        var mesg = address;
        document.getElementById("txtPlaces").value = mesg;
        var lati = latitude;
        document.getElementById("plati").value = lati;
        var longi = longitude;
        document.getElementById("plongi").value = longi;            
    });
});

How to get rid of underline for Link component of React Router?

I have resolve a problem maybe like your. I tried to inspect element in firefox. I will show you some results:

  1. It is only the element I have inspect. The "Link" component will be convert to "a" tag, and "to" props will be convert to the "href" property:

  1. And when I tick in :hov and option :hover and here is result:

As you see a:hover have text-decoration: underline. I only add to my css file:

a:hover {
 text-decoration: none;
}

and problem is resolved. But I also set text-decoration: none in some another classes (like you :D), that may be make some effects (I guess).

"ORA-01438: value larger than specified precision allowed for this column" when inserting 3

NUMBER (precision, scale) means precision number of total digits, of which scale digits are right of the decimal point.

NUMBER(2,2) in other words means a number with 2 digits, both of which are decimals. You may mean to use NUMBER(4,2) to get 4 digits, of which 2 are decimals. Currently you can just insert values with a zero integer part.

More info at the Oracle docs.

What is the difference between single and double quotes in SQL?

In ANSI SQL, double quotes quote object names (e.g. tables) which allows them to contain characters not otherwise permitted, or be the same as reserved words (Avoid this, really).

Single quotes are for strings.

However, MySQL is oblivious to the standard (unless its SQL_MODE is changed) and allows them to be used interchangably for strings.

Moreover, Sybase and Microsoft also use square brackets for identifier quoting.

So it's a bit vendor specific.

Other databases such as Postgres and IBM actually adhere to the ansi standard :)

How to list all available Kafka brokers in a cluster?

Alternate way using Zk-Client:

If you do not prefer to pass arguments to ./zookeeper-shell.sh and want to see the broker details from Zookeeper CLI, you need to install standalone Zookeeper (As traditional Kafka do not comes up with Jline JAR).

Once you install(unzip) the standalone Zookeeper,then:

  • Run the Zookeeper CLI:
    $ zookeeper/bin/zkCli.sh -server localhost:2181 #Make sure your Broker is already running

  • If it is successful, you can see the Zk client running as:

WATCHER::

WatchedEvent state:SyncConnected type:None path:null
[zk: localhost:2181(CONNECTED) 0]
  • From here you can explore the broker details using various commands:

$ ls /brokers/ids # Gives the list of active brokers
$ ls /brokers/topics #Gives the list of topics
$ get /brokers/ids/0 #Gives more detailed information of the broker id '0'

How to increase Maximum Upload size in cPanel?

Since there is no php.ini file in your /public_html directory......create a new file as phpinfo.php in /public_html directory

-Type this code in phpinfo.php and save it:

<?php phpinfo(); ?>

-Then type yourdomain.com/phpinfo.php...you will see all the details of your configuration

-To edit that config, create another file as php.ini in /public_html directory and paste this code: memory_limit=512M
post_max_size=200M
upload_max_filesize=200M

-And then refresh yourdomain.com/phpinfo.php and see the changes,it will be done.

Change the bullet color of list

I would recommend you to use background-image instead of default list.

.listStyle {
    list-style: none;
    background: url(image_path.jpg) no-repeat left center;
    padding-left: 30px;
    width: 20px;
    height: 20px;
}

Or, if you don't want to use background-image as bullet, there is an option to do it with pseudo element:

.liststyle{
    list-style: none;
    margin: 0;
    padding: 0;
}
.liststyle:before {
    content: "• ";
    color: red; /* or whatever color you prefer */
    font-size: 20px;/* or whatever the bullet size you prefer */
}

How to delete multiple files at once in Bash on Linux?

I am not a linux guru, but I believe you want to pipe your list of output files to xargs rm -rf. I have used something like this in the past with good results. Test on a sample directory first!

EDIT - I might have misunderstood, based on the other answers that are appearing. If you can use wildcards, great. I assumed that your original list that you displayed was generated by a program to give you your "selection", so I thought piping to xargs would be the way to go.

Mysql: Select rows from a table that are not in another

Try:

SELECT * FROM table1
    LEFT OUTER JOIN table2
    ON table1.FirstName = table2.FirstName and table1.LastName=table2.LastName
    WHERE table2.BirthDate IS NULL

javascript find and remove object in array based on key value

There's a new method to do this in ES6/2015 using findIndex and array spread operator:

const index = data.findIndex(obj => obj.id === id);
const newData = [
    ...data.slice(0, index),
    ...data.slice(index + 1)
]

You can turn it into a function for later reuse like this:

function remove(array, key, value) {
    const index = array.findIndex(obj => obj[key] === value);
    return index >= 0 ? [
        ...array.slice(0, index),
        ...array.slice(index + 1)
    ] : array;
}

This way you can to remove items by different keys using one method (and if there's no object that meets the criteria, you get original array returned):

const newData = remove(data, "id", "88");
const newData2 = remove(data, "name", "You are awesome!");

Or you can put it on your Array.prototype:

Array.prototype.remove = function (key, value) {
    const index = this.findIndex(obj => obj[key] === value);
    return index >= 0 ? [
        ...this.slice(0, index),
        ...this.slice(index + 1)
    ] : this;
};

And use it this way:

const newData = data.remove("id", "88");
const newData2 = data.remove("name", "You are awesome!");

Can I have multiple :before pseudo-elements for the same element?

If your main element has some child elements or text, you could make use of it.

Position your main element relative (or absolute/fixed) and use both :before and :after positioned absolute (in my situation it had to be absolute, don't know about your's).

Now if you want one more pseudo-element, attach an absolute :before to one of the main element's children (if you have only text, put it in a span, now you have an element), which is not relative/absolute/fixed.

This element will start acting like his owner is your main element.

HTML

<div class="circle">
    <span>Some text</span>
</div>

CSS

.circle {
    position: relative; /* or absolute/fixed */
}

.circle:before {
    position: absolute;
    content: "";
    /* more styles: width, height, etc */
}

.circle:after {
    position: absolute;
    content: "";
    /* more styles: width, height, etc */
}

.circle span {
    /* not relative/absolute/fixed */
}

.circle span:before {
    position: absolute;
    content: "";
    /* more styles: width, height, etc */
}

Align two divs horizontally side by side center to the page using bootstrap css

Alternative which I did programming Angular:

    <div class="form-row">
        <div class="form-group col-md-7">
             Left
        </div>
        <div class="form-group col-md-5">
             Right
        </div>
    </div>

ImportError: No module named apiclient.discovery

I encountered the same issue. This worked:

>>> import pkg_resources
>>> pkg_resources.require("google-api-python-client")
[google-api-python-client 1.5.3 (c:\python27), uritemplate 0.6 (c:\python27\lib\site-packages\uritemplate-0.6-py2.7.egg), six 1.10.0 (c:\python27\lib\site-packages\six-1.10.0-py2.7.egg), oauth2client 3.0.0 (c:\python27\lib\site-packages\oauth2client-3.0.0-py2.7.egg), httplib2 0.9.2 (c:\python27\lib\site-packages\httplib2-0.9.2-py2.7.egg), simplejson 3.8.2 (c:\python27\lib\site-packages\simplejson-3.8.2-py2.7-win32.egg), six 1.10.0 (c:\python27\lib\site-packages\six-1.10.0-py2.7.egg), rsa 3.4.2 (c:\python27\lib\site-packages\rsa-3.4.2-py2.7.egg), pyasn1-modules 0.0.8 (c:\python27\lib\site-packages\pyasn1_modules-0.0.8-py2.7.egg), pyasn1 0.1.9 (c:\python27\lib\site-packages\pyasn1-0.1.9-py2.7.egg)]

>>> from apiclient.discovery import build
>>> 

R Error in x$ed : $ operator is invalid for atomic vectors

Here x is a vector. You need to convert it into a dataframe for using $ operator.

 x <- as.data.frame(x) 

will work for you.

x<-c(1,2)
names(x)<- c("bob","ed")
x <- as.data.frame(x)

will give you output of x as:
bob 1
ed 2
And, will give you output of x$ed as:
NULL
If you want bob and ed as column names then you need to transpose the dataframe like x <- as.data.frame(t(x)) So your code becomes

x<-c(1,2)
x
names(x)<- c("bob","ed")
x$ed
x <- as.data.frame(t(x))

Now the output of x$ed is:
[1] 2

NSInternalInconsistencyException', reason: 'Could not load NIB in bundle: 'NSBundle

In my case, this happen because of I deleted the Main.storyboard and in general tab Main Interface property cleared and added custom one as Start. After I Change the Main Interface to Start.storyboard except Start it's working.

What is the difference between Release and Debug modes in Visual Studio?

The main difference is when compiled in debug mode, pdb files are also created which allow debugging (so you can step through the code when its running). This however means that the code isn't optimized as much.

Why not inherit from List<T>?

What the guidelines say is that the public API should not reveal the internal design decision of whether you are using a list, a set, a dictionary, a tree or whatever. A "team" is not necessarily a list. You may implement it as a list but users of your public API should use you class on a need to know basis. This allows you to change your decision and use a different data structure without affecting the public interface.

How to set the environmental variable LD_LIBRARY_PATH in linux

Put export LD_LIBRARY_PATH=/usr/local/lib in ~/.bashrc [preferably towards end of script to avoid any overrides in between, Default ~/.bashrc comes with many if-else statements]

Post that whenever you open a new terminal/konsole, LD_LIBRARY_PATH will be reflected

assign headers based on existing row in dataframe in R

The key here is to unlist the row first.

colnames(DF) <- as.character(unlist(DF[1,]))
DF = DF[-1, ]

How do you properly use WideCharToMultiByte

You use the lpMultiByteStr [out] parameter by creating a new char array. You then pass this char array in to get it filled. You only need to initialize the length of the string + 1 so that you can have a null terminated string after the conversion.

Here are a couple of useful helper functions for you, they show the usage of all parameters.

#include <string>

std::string wstrtostr(const std::wstring &wstr)
{
    // Convert a Unicode string to an ASCII string
    std::string strTo;
    char *szTo = new char[wstr.length() + 1];
    szTo[wstr.size()] = '\0';
    WideCharToMultiByte(CP_ACP, 0, wstr.c_str(), -1, szTo, (int)wstr.length(), NULL, NULL);
    strTo = szTo;
    delete[] szTo;
    return strTo;
}

std::wstring strtowstr(const std::string &str)
{
    // Convert an ASCII string to a Unicode String
    std::wstring wstrTo;
    wchar_t *wszTo = new wchar_t[str.length() + 1];
    wszTo[str.size()] = L'\0';
    MultiByteToWideChar(CP_ACP, 0, str.c_str(), -1, wszTo, (int)str.length());
    wstrTo = wszTo;
    delete[] wszTo;
    return wstrTo;
}

--

Anytime in documentation when you see that it has a parameter which is a pointer to a type, and they tell you it is an out variable, you will want to create that type, and then pass in a pointer to it. The function will use that pointer to fill your variable.

So you can understand this better:

//pX is an out parameter, it fills your variable with 10.
void fillXWith10(int *pX)
{
  *pX = 10;
}

int main(int argc, char ** argv)
{
  int X;
  fillXWith10(&X);
  return 0;
}

Is there a Pattern Matching Utility like GREP in Windows?

As mentioned above, the gnuwin32 project has a Windows CLI version of grep.

If you want something with a graphical interface, I would recommend the (open-source) tool AstroGrep.

Foreach value from POST from form

i wouldn't do it this way

I'd use name arrays in the form elements

so i'd get the layout

$_POST['field'][0]['name'] = 'value';
$_POST['field'][0]['price'] = 'value';
$_POST['field'][1]['name'] = 'value';
$_POST['field'][1]['price'] = 'value';

then you could do an array slice to get the amount you need

Can Mockito capture arguments of a method called multiple times?

If you don't want to validate all the calls to doSomething(), only the last one, you can just use ArgumentCaptor.getValue(). According to the Mockito javadoc:

If the method was called multiple times then it returns the latest captured value

So this would work (assumes Foo has a method getName()):

ArgumentCaptor<Foo> fooCaptor = ArgumentCaptor.forClass(Foo.class);
verify(mockBar, times(2)).doSomething(fooCaptor.capture());
//getValue() contains value set in second call to doSomething()
assertEquals("2nd one", fooCaptor.getValue().getName());

How can I select rows with most recent timestamp for each key value?

There is one common answer I haven't see here yet, which is the Window Function. It is an alternative to the correlated sub-query, if your DB supports it.

SELECT sensorID,timestamp,sensorField1,sensorField2 
FROM (
    SELECT sensorID,timestamp,sensorField1,sensorField2
        , ROW_NUMBER() OVER(
            PARTITION BY sensorID
            ORDER BY timestamp
        ) AS rn
    FROM sensorTable s1
WHERE rn = 1
ORDER BY sensorID, timestamp;

I acually use this more than correlated sub-queries. Feel free to bust me in the comments over effeciancy, I'm not too sure how it stacks up in that regard.

In Eclipse, what can cause Package Explorer "red-x" error-icon when all Java sources compile without errors?

yeah, this happens sometimes for no apparent reason. You can go to the "Problems"-Tab (right next to console output) and see the error message, so maybe you can narrow it down that way.

JQuery: if div is visible

You can use .is(':visible')

Selects all elements that are visible.

For example:

if($('#selectDiv').is(':visible')){

Also, you can get the div which is visible by:

$('div:visible').callYourFunction();

Live example:

_x000D_
_x000D_
console.log($('#selectDiv').is(':visible'));_x000D_
console.log($('#visibleDiv').is(':visible'));
_x000D_
#selectDiv {_x000D_
  display: none;  _x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<div id="selectDiv"></div>_x000D_
<div id="visibleDiv"></div>
_x000D_
_x000D_
_x000D_

force browsers to get latest js and css files in asp.net application

The main problem with doing it this way is mainly that you will need to remember to update your version number in your code every time you make any change to your css or js files.

A possibly better way to do it is to set a guaranteed unique parameter with each of your css or js files, like so:

<script src="scripts/myjavascript.js?_=<%=DateTime.Now.Ticks%>" type="text/javascript"></script>
<link href="styles/mystyle.css?_=<%=DateTime.Now.Ticks%>" rel="stylesheet" type="text/css" />

This forces the files to be requested from the server every single time, which also means that your site will not be as performant upon page load, since those files will never be cached, and will use unneeded bandwidth each time.

Essentially, if you can remember to update the version number every time a change is made, you can get away with how you're doing it.

Efficient way to apply multiple filters to pandas DataFrame or Series

e can also select rows based on values of a column that are not in a list or any iterable. We will create boolean variable just like before, but now we will negate the boolean variable by placing ~ in the front.

For example

list = [1, 0]
df[df.col1.isin(list)]

Python concatenate text files

Check out the .read() method of the File object:

http://docs.python.org/2/tutorial/inputoutput.html#methods-of-file-objects

You could do something like:

concat = ""
for file in files:
    concat += open(file).read()

or a more 'elegant' python-way:

concat = ''.join([open(f).read() for f in files])

which, according to this article: http://www.skymind.com/~ocrow/python_string/ would also be the fastest.

How to delete or change directory of a cloned git repository on a local computer

Just move it :)

command line :

move "C:\Documents and Setings\$USER\project" C:\project

or just drag the folder in explorer.

Git won't care where it is - all the metadata for the repository is inside a folder called .git inside your project folder.

How does Git handle symbolic links?

"Editor's" note: This post may contain outdated information. Please see comments and this question regarding changes in Git since 1.6.1.

Symlinked directories:

It's important to note what happens when there is a directory which is a soft link. Any Git pull with an update removes the link and makes it a normal directory. This is what I learnt hard way. Some insights here and here.

Example

Before

 ls -l
 lrwxrwxrwx 1 admin adm   29 Sep 30 15:28 src/somedir -> /mnt/somedir

git add/commit/push

It remains the same

After git pull AND some updates found

 drwxrwsr-x 2 admin adm 4096 Oct  2 05:54 src/somedir

JavaScript split String with white space

You could split the string on the whitespace and then re-add it, since you know its in between every one of the entries.

var string = "text to split";
    string = string.split(" ");
var stringArray = new Array();
for(var i =0; i < string.length; i++){
    stringArray.push(string[i]);
    if(i != string.length-1){
        stringArray.push(" ");
    }
}

Update: Removed trailing space.

Undefined reference to 'vtable for xxx'

The first set of errors, for the missing vtable, are caused because you do not implement takeaway::textualGame(); instead you implement a non-member function, textualGame(). I think that adding the missing takeaway:: will fix that.

The cause of the last error is that you're calling a virtual function, initialData(), from the constructor of gameCore. At this stage, virtual functions are dispatched according to the type currently being constructed (gameCore), not the most derived class (takeaway). This particular function is pure virtual, and so calling it here gives undefined behaviour.

Two possible solutions:

  • Move the initialisation code for gameCore out of the constructor and into a separate initialisation function, which must be called after the object is fully constructed; or
  • Separate gameCore into two classes: an abstract interface to be implemented by takeaway, and a concrete class containing the state. Construct takeaway first, and then pass it (via a reference to the interface class) to the constructor of the concrete class.

I would recommend the second, as it is a move towards smaller classes and looser coupling, and it will be harder to use the classes incorrectly. The first is more error-prone, as there is no way be sure that the initialisation function is called correctly.

One final point: the destructor of a base class should usually either be virtual (to allow polymorphic deletion) or protected (to prevent invalid polymorphic deletion).

Linq select to new object

If you want to be able to perform a lookup on each type to get its frequency then you will need to transform the enumeration into a dictionary.

var types = new[] {typeof(string), typeof(string), typeof(int)};
var x = types
        .GroupBy(type => type)
        .ToDictionary(g => g.Key, g => g.Count());
foreach (var kvp in x) {
    Console.WriteLine("Type {0}, Count {1}", kvp.Key, kvp.Value);
}
Console.WriteLine("string has a count of {0}", x[typeof(string)]);