Programs & Examples On #Bitkeeper

BitKeeper is a distributed source-code-management-system.

How to set a hidden value in Razor

There is a Hidden helper alongside HiddenFor which lets you set the value.

@Html.Hidden("RequiredProperty", "default")

EDIT Based on the edit you've made to the question, you could do this, but I believe you're moving into territory where it will be cheaper and more effective, in the long run, to fight for making the code change. As has been said, even by yourself, the controller or view model should be setting the default.

This code:

<ul>
@{
        var stacks = new System.Diagnostics.StackTrace().GetFrames();
        foreach (var frame in stacks)
        {
            <li>@frame.GetMethod().Name - @frame.GetMethod().DeclaringType</li>
        }
}
</ul>

Will give output like this:

Execute - ASP._Page_Views_ViewDirectoryX__SubView_cshtml
ExecutePageHierarchy - System.Web.WebPages.WebPageBase
ExecutePageHierarchy - System.Web.Mvc.WebViewPage
ExecutePageHierarchy - System.Web.WebPages.WebPageBase
RenderView - System.Web.Mvc.RazorView
Render - System.Web.Mvc.BuildManagerCompiledView
RenderPartialInternal - System.Web.Mvc.HtmlHelper
RenderPartial - System.Web.Mvc.Html.RenderPartialExtensions
Execute - ASP._Page_Views_ViewDirectoryY__MainView_cshtml

So assuming the MVC framework will always go through the same stack, you can grab var frame = stacks[8]; and use the declaring type to determine who your parent view is, and then use that determination to set (or not) the default value. You could also walk the stack instead of directly grabbing [8] which would be safer but even less efficient.

C subscripted value is neither array nor pointer nor vector when assigning an array element value

C lets you use the subscript operator [] on arrays and on pointers. When you use this operator on a pointer, the resultant type is the type to which the pointer points to. For example, if you apply [] to int*, the result would be an int.

That is precisely what's going on: you are passing int*, which corresponds to a vector of integers. Using subscript on it once makes it int, so you cannot apply the second subscript to it.

It appears from your code that arr should be a 2-D array. If it is implemented as a "jagged" array (i.e. an array of pointers) then the parameter type should be int **.

Moreover, it appears that you are trying to return a local array. In order to do that legally, you need to allocate the array dynamically, and return a pointer. However, a better approach would be declaring a special struct for your 4x4 matrix, and using it to wrap your fixed-size array, like this:

// This type wraps your 4x4 matrix
typedef struct {
    int arr[4][4];
} FourByFour;
// Now rotate(m) can use FourByFour as a type
FourByFour rotate(FourByFour m) {
    FourByFour D;
    for(int i = 0; i < 4; i ++ ){
        for(int n = 0; n < 4; n++){
            D.arr[i][n] = m.arr[n][3 - i];
        }
    }
    return D;
}
// Here is a demo of your rotate(m) in action:
int main(void) {
    FourByFour S = {.arr = {
        { 1, 4, 10, 3 },
        { 0, 6, 3, 8 },
        { 7, 10 ,8, 5 },
        { 9, 5, 11, 2}
    } };
    FourByFour r = rotate(S);
    for(int i=0; i < 4; i ++ ){
        for(int n=0; n < 4; n++){
            printf("%d ", r.arr[i][n]);
        }
        printf("\n");
    }
    return 0;
}

This prints the following:

3 8 5 2 
10 3 8 11 
4 6 10 5 
1 0 7 9 

Save internal file in my own internal folder in Android

First Way:

You didn't create the directory. Also, you are passing an absolute path to openFileOutput(), which is wrong.

Second way:

You created an empty file with the desired name, which then prevented you from creating the directory. Also, you are passing an absolute path to openFileOutput(), which is wrong.

Third way:

You didn't create the directory. Also, you are passing an absolute path to openFileOutput(), which is wrong.

Fourth Way:

You didn't create the directory. Also, you are passing an absolute path to openFileOutput(), which is wrong.

Fifth way:

You didn't create the directory. Also, you are passing an absolute path to openFileOutput(), which is wrong.

Correct way:

  1. Create a File for your desired directory (e.g., File path=new File(getFilesDir(),"myfolder");)
  2. Call mkdirs() on that File to create the directory if it does not exist
  3. Create a File for the output file (e.g., File mypath=new File(path,"myfile.txt");)
  4. Use standard Java I/O to write to that File (e.g., using new BufferedWriter(new FileWriter(mypath)))

How to show disable HTML select option in by default?

You can set which option is selected by default like this:

<option value="" selected>Choose Tagging</option>

I would suggest using javascript and JQuery to observe for click event and disable the first option after another has been selected: First, give the element an ID like so:

<select id="option_select" name="tagging">

and the option an id :

<option value="" id="initial">Choose Tagging</option>

then:

<script type="text/javascript">

$('option_select').observe(click, handleClickFunction);

Then you just create the function:

function handleClickFunction () {

if ($('option_select').value !== "option_select") 
{
   $('initial').disabled=true; }
}

How do I write a SQL query for a specific date range and date time using SQL Server 2008?

SELECT * FROM TABLE
WHERE DATE BETWEEN '09/16/2010 05:00:00' and '09/21/2010 09:00:00'

How to connect to LocalDb

You can connect with MSSMS to LocalDB. Type only in SERVER NAME: (localdb)\v11.0 and leave it by Windows Authentication and it connects to your LocalDB server and shows you the databases in it.

Sharing link on WhatsApp from mobile website (not application) for Android

Currently, it's very easy to achieve this. You only need to add the following code to your pages:

<a href="whatsapp://send?text=<<HERE GOES THE URL ENCODED TEXT YOU WANT TO SHARE>>" data-action="share/whatsapp/share">Share via Whatsapp</a>

And that's it. No Javascript needed, nothing else needed. Of course you can style it as you want and include a nice Whatsapp icon.

I tested this in my Android device with Google Chrome. The versions:

  • Android 4.1.2 (Jelly Bean)
  • Chrome Mobile 37.0.2062.117. Also tested on Firefox Mobile 31.0.
  • Whatsapp V 2.11.399

It also works on iOS. I've made a quick test on an iPhone 5 with Safari and it works as well.

Hope this helps someone. :-)

How do I select the "last child" with a specific class name in CSS?

You can't target the last instance of the class name in your list without JS.

However, you may not be entirely out-of-css-luck, depending on what you are wanting to achieve. For example, by using the next sibling selector, I have added a visual divider after the last of your .list elements here: http://jsbin.com/vejixisudo/edit?html,css,output

Remove items from one list in another

You can use Except:

List<car> list1 = GetTheList();
List<car> list2 = GetSomeOtherList();
List<car> result = list2.Except(list1).ToList();

You probably don't even need those temporary variables:

List<car> result = GetSomeOtherList().Except(GetTheList()).ToList();

Note that Except does not modify either list - it creates a new list with the result.

Including jars in classpath on commandline (javac or apt)

Using:

apt HelloImpl.java -classpath /sac/tools/thirdparty/jaxws-ri/jaxws-ri-2.1.4/lib/jsr181-api.jar:.

works but it gives me another error, see new question

How to ping ubuntu guest on VirtualBox

In most cases simply switching the virtual machine network adapter to bridged mode is enough to make the guest machine accessible from outside.

Switching virtual machine network adapter type

Sometimes it's possible for the guest machine to not automatically receive an IP which matches the host's IP range after switching to bridged mode (even after rebooting the guest machine). This is often caused by a malfunctioning or badly configured DHCP on the host network.

For example, if the host IP is 192.168.1.1 the guest machine needs to have an IP in the format 192.168.1.* where only the last group of numbers is allowed to be different from the host IP.

You can use a terminal (shell) and type ifconfig (ipconfig for Windows guests) to check what IP is assigned to the guest machine and change it if required.

Getting the guest's machine IP

If the host and guest IPs do not match simply setting a static IP for the guest machine explicitly should resolve the issue.

How do I change UIView Size?

This can be achieved in various methods in Swift 3.0 Worked on Latest version MAY- 2019

Directly assign the Height & Width values for a view:

userView.frame.size.height = 0

userView.frame.size.width = 10

Assign the CGRect for the Frame

userView.frame =  CGRect(x:0, y: 0, width:0, height:0)

Method Details:

CGRect(x: point of X, y: point of Y, width: Width of View, height: Height of View)

Using an Extension method for CGRECT

Add following extension code in any swift file,

extension CGRect {

    init(_ x:CGFloat, _ y:CGFloat, _ w:CGFloat, _ h:CGFloat) {

        self.init(x:x, y:y, width:w, height:h)
    }
}

Use the following code anywhere in your application for the view to set the size parameters

userView.frame =  CGRect(1, 1, 20, 45)

How to save password when using Subversion from the console

None of these wonderful answers worked for me on a fresh install of Ubuntu. Instead, a clue from this answer did the trick for me.

I had to allow "simple" password store by setting this empty in ~/.subversion/config:

password-stores =

There was no existing setting, so being empty is significant.

This was in addition to:

store-passwords = yes

in ~/.subversion/servers.

Exporting the values in List to excel

Using the CSV idea, if it's just a list of Strings. Assuming l is your list:

using System.IO;

using(StreamWriter sw = File.CreateText("list.csv"))
{
  for(int i = 0; i < l.Count; i++)
  {
    sw.WriteLine(l[i]);
  }
}

sqlite3.ProgrammingError: Incorrect number of bindings supplied. The current statement uses 1, and there are 74 supplied

cursor.execute(sql,array)

Only takes two arguments.
It will iterate the "array"-object and match ? in the sql-string.
(with sanity checks to avoid sql-injection)

what is the difference between json and xml

They're two different ways of representing data, but they're pretty dissimilar. The wikipedia pages for JSON and XML give some examples of each, and there's a comparison paragraph

NGINX to reverse proxy websockets AND enable SSL (wss://)?

for .net core 2.0 Nginx with SSL

location / {
    # redirect all HTTP traffic to localhost:8080
    proxy_pass http://localhost:8080;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header Host $host;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

    # WebSocket support
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection $http_connection;
}

This worked for me

How to add noise (Gaussian/salt and pepper etc) to image in Python with OpenCV

I don't know is there any method in Python API.But you can use this simple code to add Salt-and-Pepper noise to an image.

import numpy as np
import random
import cv2

def sp_noise(image,prob):
    '''
    Add salt and pepper noise to image
    prob: Probability of the noise
    '''
    output = np.zeros(image.shape,np.uint8)
    thres = 1 - prob 
    for i in range(image.shape[0]):
        for j in range(image.shape[1]):
            rdn = random.random()
            if rdn < prob:
                output[i][j] = 0
            elif rdn > thres:
                output[i][j] = 255
            else:
                output[i][j] = image[i][j]
    return output

image = cv2.imread('image.jpg',0) # Only for grayscale image
noise_img = sp_noise(image,0.05)
cv2.imwrite('sp_noise.jpg', noise_img)

How to check for a valid URL in Java?

The most "foolproof" way is to check for the availability of URL:

public boolean isURL(String url) {
  try {
     (new java.net.URL(url)).openStream().close();
     return true;
  } catch (Exception ex) { }
  return false;
}

Java 8 method references: provide a Supplier capable of supplying a parameterized result

optionalUsers.orElseThrow(() -> new UsernameNotFoundException("Username not found"));

Can I get "&&" or "-and" to work in PowerShell?

It depends on the context, but here's an example of "-and" in action:

get-childitem | where-object { $_.Name.StartsWith("f") -and $_.Length -gt 10kb }

So that's getting all the files bigger than 10kb in a directory whose filename starts with "f".

How do you use bcrypt for hashing passwords in PHP?

The password_hash() function in PHP is an inbuilt function , used to create a new password hash with different algorithms and options. the function uses a strong hashing algorithm.

the function take 2 mandetory parametres ($password and $algorithm,) and 1 optional parameter ($options).

$strongPassword = password_hash( $password, $algorithm, $options )


Algoristrong textthms allowed right now for password_hash() are :

  • PASSWORD_DEFAULT

  • PASSWORD_BCRYPT

  • ASSWORD_ARGON2I

  • PASSWORD_ARGON2ID


example : echo password_hash("abcDEF", PASSWORD_DEFAULT);

answer : $2y$10$KwKceUaG84WInAif5ehdZOkE4kHPWTLp0ZK5a5OU2EbtdwQ9YIcGy


example: `echo password_hash("abcDEF", PASSWORD_BCRYPT);`

answer :$2y$10$SNly5bFzB/R6OVbBMq1bj.yiOZdsk6Mwgqi4BLR2sqdCvMyv/AyL2


to use the BCRYPT as password, use option cost =12 in an array , also change 1st parameter $password to some strong password like "wgt167yuWBGY@#1987__"

Example: echo password_hash("wgt167yuWBGY@#1987__", PASSWORD_BCRYPT ,['cost' => 12]);

Answer : $2y$12$TjSggXiFSidD63E.QP8PJOds2texJfsk/82VaNU8XRZ/niZhzkJ6S

Unordered List (<ul>) default indent

Most html tags have some default properties. A css reset will help you change the default properties.

What I usually do is:

{ padding: 0; margin: 0; font-face:Arial; }

Although the font is up to you!

Padding In bootstrap

I have not used Bootstrap but I worked on Zurb Foundation. On that I used to add space like this.

<div id="main" class="container" role="main">
    <div class="row">

        <div class="span5 offset1">
            <h2>Welcome</h2>
            <p>Hello and welcome to my website.</p>
        </div>
        <div class="span6">
            Image Here (TODO)
        </div>
    </div>

Visit this link: http://getbootstrap.com/2.3.2/scaffolding.html and read the section: Offsetting columns.

I think I know what you are doing wrong. If you are applying padding to the span6 like this:

<div class="span6" style="padding-left:5px;">
    <h2>Welcome</h2>
    <p>Hello and welcome to my website.</p>
</div>

It is wrong. What you have to do is add padding to the elements inside:

<div class="span6">
    <h2 style="padding-left:5px;">Welcome</h2>
    <p  style="padding-left:5px;">Hello and welcome to my website.</p>
</div>

Tower of Hanoi: Recursive Algorithm

/** * */ package com.test.recursion;

/** * @author kamals1986 The Recursive algorithm for Tower of Hanoi Problem The * algorithm grows by power(2,n). */ public class TowerOfHanoi {

private static String SOURCE_PEG = "B";

private static String SPARE_PEG = "C";

private static String TARGET_PEG = "A";

public void listSteps(int n, String source, String target, String spare) {
    if (n == 1) {
        System.out.println("Please move from Peg " + source + "\tTo Peg\t"
                + target);
    } else {
        listSteps(n - 1, source, spare, target);
        listSteps(1, source, target, spare);
        listSteps(n - 1, spare, target, source);
    }
}

public static void main(String[] args) {
    long startTime = System.currentTimeMillis();
    new TowerOfHanoi().listSteps(18, SOURCE_PEG, TARGET_PEG, SPARE_PEG);

    long endTime = System.currentTimeMillis();

    System.out.println("Done in " + (endTime - startTime) / 1000
            + "\t seconds");
}

}

How to pass parameter to click event in Jquery

As DOC says, you can pass data to the handler as next:

// say your selector and click handler looks something like this...
$("some selector").on('click',{param1: "Hello", param2: "World"}, cool_function);

// in your function, just grab the event object and go crazy...
function cool_function(event){
    alert(event.data.param1);
    alert(event.data.param2);

    // access element's id where click occur
    alert( event.target.id ); 
}

What are OLTP and OLAP. What is the difference between them?

The difference is quite simple:

OLTP (Online Transaction Processing)

OLTP is a class of information systems that facilitate and manage transaction-oriented applications. OLTP has also been used to refer to processing in which the system responds immediately to user requests. Online transaction processing applications are high throughput and insert or update-intensive in database management. Some examples of OLTP systems include order entry, retail sales, and financial transaction systems.

OLAP (Online Analytical Processing)

OLAP is part of the broader category of business intelligence, which also encompasses relational database, report writing and data mining. Typical applications of OLAP include business reporting for sales, marketing, management reporting, business process management (BPM), budgeting and forecasting, financial reporting and similar areas.

See more details OLTP and OLAP

Xcode 6: Keyboard does not show up in simulator

To enable/disable simulator keyboard: click ?+?+K to show the keyboard on simulator, click again to disable (hide) the keyboard.

Is the LIKE operator case-sensitive with MSSQL Server?

You have an option to define collation order at the time of defining your table. If you define a case-sensitive order, your LIKE operator will behave in a case-sensitive way; if you define a case-insensitive collation order, the LIKE operator will ignore character case as well:

CREATE TABLE Test (
    CI_Str VARCHAR(15) COLLATE Latin1_General_CI_AS -- Case-insensitive
,   CS_Str VARCHAR(15) COLLATE Latin1_General_CS_AS -- Case-sensitive
);

Here is a quick demo on sqlfiddle showing the results of collation order on searches with LIKE.

React Router Pass Param to Component

try this.

<Route exact path="/details/:id" render={(props)=>{return(
    <DetailsPage id={props.match.params.id}/>)
}} />

In details page try this...

this.props.id

How can I get all sequences in an Oracle database?

You may not have permission to dba_sequences. So you can always just do:

select * from user_sequences;

How to deal with page breaks when printing a large HTML table

I checked many solutions and anyone wasn't working good.

So I tried a small trick and it works:

tfoot with style:position: fixed; bottom: 0px; is placed at the bottom of last page, but if footer is too high it is overlapped by content of table.

tfoot with only: display: table-footer-group; isn't overlapped, but is not on the bottom of last page...

Let's put two tfoot:

_x000D_
_x000D_
TFOOT.placer {_x000D_
  display: table-footer-group;_x000D_
  height: 130px;_x000D_
}_x000D_
_x000D_
TFOOT.contenter {_x000D_
  display: table-footer-group;_x000D_
  position: fixed;_x000D_
  bottom: 0px; _x000D_
  height: 130px;_x000D_
}
_x000D_
<TFOOT  class='placer'> _x000D_
  <TR>_x000D_
    <TD>_x000D_
      <!--  empty here_x000D_
-->_x000D_
    </TD>_x000D_
  </TR>_x000D_
</TFOOT> _x000D_
<TFOOT  class='contenter'> _x000D_
  <TR>_x000D_
    <TD>_x000D_
      your long text or high image here_x000D_
    </TD>_x000D_
  </TR>_x000D_
</TFOOT>
_x000D_
_x000D_
_x000D_

One reserves place on non-last pages, second puts in your accual footer.

git reset --hard HEAD leaves untracked files behind

You might have done a soft reset at some point, you can solve this problem by doing

git add .
git reset --hard HEAD~100
git pull

How do I verify/check/test/validate my SSH passphrase?

Extending @RobBednark's solution to a specific Windows + PuTTY scenario, you can do so:

  1. Generate SSH key pair with PuTTYgen (following Manually generating your SSH key in Windows), saving it to a PPK file;

  2. With the context menu in Windows Explorer, choose Edit with PuTTYgen. It will prompt for a password.

If you type the wrong password, it will just prompt again.

Note, if you like to type, use the following command on a folder that contains the PPK file: puttygen private-key.ppk -y.

How to pass object with NSNotificationCenter

Building on the solution provided I thought it might be helpful to show an example passing your own custom data object (which I've referenced here as 'message' as per question).

Class A (sender):

YourDataObject *message = [[YourDataObject alloc] init];
// set your message properties
NSDictionary *dict = [NSDictionary dictionaryWithObject:message forKey:@"message"];
[[NSNotificationCenter defaultCenter] postNotificationName:@"NotificationMessageEvent" object:nil userInfo:dict];

Class B (receiver):

- (void)viewDidLoad
{
    [super viewDidLoad];
    [[NSNotificationCenter defaultCenter]
     addObserver:self selector:@selector(triggerAction:) name:@"NotificationMessageEvent" object:nil];
}

#pragma mark - Notification
-(void) triggerAction:(NSNotification *) notification
{
    NSDictionary *dict = notification.userInfo;
    YourDataObject *message = [dict valueForKey:@"message"];
    if (message != nil) {
        // do stuff here with your message data
    }
}

SQL 'LIKE' query using '%' where the search criteria contains '%'

Use an escape clause:

select *
  from (select '123abc456' AS result from dual
        union all
        select '123abc%456' AS result from dual
       )
  WHERE result LIKE '%abc\%%' escape '\'

Result

123abc%456

You can set your escape character to whatever you want. In this case, the default '\'. The escaped '\%' becomes a literal, the second '%' is not escaped, so again wild card.

See List of special characters for SQL LIKE clause

.bashrc at ssh login

I had similar situation like Hobhouse. I wanted to use command

 ssh myhost.com 'some_command'

and 'some_command' exists in '/var/some_location' so I tried to append '/var/some_location' in PATH environment by editing '$HOME/.bashrc'

but that wasn't working. because default .bashrc(Ubuntu 10.4 LTS) prevent from sourcing by code like below

# If not running interactively, don't do anything
[ -z "$PS1" ] && return

so If you want to change environment for ssh non-login shell. you should add code above that line.

How to make an HTML back link?

This solution gives you the best of both worlds

  • Users get to hover over the link to see the URL
  • Users don't end up with a corrupted back-stack

More details in the code comments below.

_x000D_
_x000D_
var element = document.getElementById('back-link');_x000D_
_x000D_
// Provide a standard href to facilitate standard browser features such as _x000D_
//  - Hover to see link_x000D_
//  - Right click and copy link_x000D_
//  - Right click and open in new tab_x000D_
element.setAttribute('href', document.referrer);_x000D_
_x000D_
// We can't let the browser use the above href for navigation. If it does, _x000D_
// the browser will think that it is a regular link, and place the current _x000D_
// page on the browser history, so that if the user clicks "back" again,_x000D_
// it'll actually return to this page. We need to perform a native back to_x000D_
// integrate properly into the browser's history behavior_x000D_
element.onclick = function() {_x000D_
  history.back();_x000D_
  return false;_x000D_
}
_x000D_
<a id="back-link">back</a>
_x000D_
_x000D_
_x000D_

Does Python have a string 'contains' substring method?

Here is your answer:

if "insert_char_or_string_here" in "insert_string_to_search_here":
    #DOSTUFF

For checking if it is false:

if not "insert_char_or_string_here" in "insert_string_to_search_here":
    #DOSTUFF

OR:

if "insert_char_or_string_here" not in "insert_string_to_search_here":
    #DOSTUFF

Java correct way convert/cast object to Double



Also worth mentioning -- if you were forced to use an older Java version prior to 1.5, and you are trying to use Collections, you won't be able to parameterize the collection with a type such as Double.

You'll have to manually "box" to the class Double when adding new items, and "unbox" to the primitive double by parsing and casting, doing something like this:

LinkedList lameOldList = new LinkedList();
lameOldList.add( new Double(1.2) );
lameOldList.add( new Double(3.4) );
lameOldList.add( new Double(5.6) );

double total = 0.0;
for (int i = 0, len = lameOldList.size(); i < len; i++) {
  total += Double.valueOf( (Double)lameOldList.get(i) );
}


The old-school list will contain only type Object and so has to be cast to Double.

Also, you won't be able to iterate through the list with an enhanced-for-loop in early Java versions -- only with a for-loop.

How do I hide javascript code in a webpage?

Use Html Encrypter The part of the Head which has

<link rel="stylesheet" href="styles/css.css" type="text/css" media="screen" />
<script type="text/javascript" src="script/js.js" language="javascript"></script>

copy and paste it to HTML Encrypter and the Result will goes like this
and paste it the location where you cut the above sample

<Script Language='Javascript'>
<!-- HTML Encryption provided by iWEBTOOL.com -->
<!--
document.write(unescape('%3C%6C%69%6E%6B%20%72%65%6C%3D%22%73%74%79%6C%65%73%68%65%65%74%22%20%68%72%65%66%3D%22%73%74%79%6C%65%73%2F%63%73%73%2E%63%73%73%22%20%74%79%70%65%3D%22%74%65%78%74%2F%63%73%73%22%20%6D%65%64%69%61%3D%22%73%63%72%65%65%6E%22%20%2F%3E%0A%3C%73%63%72%69%70%74%20%74%79%70%65%3D%22%74%65%78%74%2F%6A%61%76%61%73%63%72%69%70%74%22%20%73%72%63%3D%22%73%63%72%69%70%74%2F%6A%73%2E%6A%73%22%20%6C%61%6E%67%75%61%67%65%3D%22%6A%61%76%61%73%63%72%69%70%74%22%3E%3C%2F%73%63%72%69%70%74%3E%0A'));
//-->

HTML ENCRYPTER Note: if you have a java script in your page try to export to .js file and make it like as the example above.

And Also this Encrypter is not always working in some code that will make ur website messed up... Select the best part you want to hide like for example in <form> </form>

This can be reverse by advance user but not all noob like me knows it.

Hope this will help

Difference between Node object and Element object?

Element inherits from Node, in the same way that Dog inherits from Animal.

An Element object "is-a" Node object, in the same way that a Dog object "is-a" Animal object.

Node is for implementing a tree structure, so its methods are for firstChild, lastChild, childNodes, etc. It is more of a class for a generic tree structure.

And then, some Node objects are also Element objects. Element inherits from Node. Element objects actually represents the objects as specified in the HTML file by the tags such as <div id="content"></div>. The Element class define properties and methods such as attributes, id, innerHTML, clientWidth, blur(), and focus().

Some Node objects are text nodes and they are not Element objects. Each Node object has a nodeType property that indicates what type of node it is, for HTML documents:

1: Element node
3: Text node
8: Comment node
9: the top level node, which is document

We can see some examples in the console:

> document instanceof Node
  true

> document instanceof Element
  false

> document.firstChild
  <html>...</html>

> document.firstChild instanceof Node
  true

> document.firstChild instanceof Element
  true

> document.firstChild.firstChild.nextElementSibling
  <body>...</body>

> document.firstChild.firstChild.nextElementSibling === document.body
  true

> document.firstChild.firstChild.nextSibling
  #text

> document.firstChild.firstChild.nextSibling instanceof Node
  true

> document.firstChild.firstChild.nextSibling instanceof Element
  false

> Element.prototype.__proto__ === Node.prototype
  true

The last line above shows that Element inherits from Node. (that line won't work in IE due to __proto__. Will need to use Chrome, Firefox, or Safari).

By the way, the document object is the top of the node tree, and document is a Document object, and Document inherits from Node as well:

> Document.prototype.__proto__ === Node.prototype
  true

Here are some docs for the Node and Element classes:
https://developer.mozilla.org/en-US/docs/DOM/Node
https://developer.mozilla.org/en-US/docs/DOM/Element

How to draw circle by canvas in Android?

If you are using your own CustomView extending View class, you need to call canvas.invalidate() method which will internally call onDraw method. You can use default API for canvas to draw a circle. The x, y cordinate define the center of the circle. You can also define color and styling in paint & pass the paint object.

public class CustomView extends View {

    public CustomView(Context context,  AttributeSet attrs) {
        super(context, attrs);
        setupPaint();
    }
}

Define default paint settings and canvas (Initialise paint in constructor so that you can reuse the same object everywhere and change only specific settings wherever required)

private Paint drawPaint;

// Setup paint with color and stroke styles
private void setupPaint() {
    drawPaint = new Paint();
    drawPaint.setColor(Color.BLUE);
    drawPaint.setAntiAlias(true);
    drawPaint.setStrokeWidth(5);
    drawPaint.setStyle(Paint.Style.FILL_AND_STROKE);
    drawPaint.setStrokeJoin(Paint.Join.ROUND);
    drawPaint.setStrokeCap(Paint.Cap.ROUND);
}

And initialise canvas object

private Canvas canvas;

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    this.canvas = canvas;
    canvas.drawCircle(xCordinate, yCordinate, RADIUS, drawPaint);
}

And finally, for every view refresh or new draw on the screen, you need to call invalidate method. Remember your entire view is redrawn, hence this is an expensive call. Make sure you do only the necessary operations in onDraw

canvas.invalidate();

For more details on canvas drawing refer https://medium.com/@mayuri.k18/android-canvas-for-drawing-and-custom-views-e1a3e90d468b

Why can't DateTime.ParseExact() parse "9/1/2009" using "M/d/yyyy"

Try :

Configure in web config file

<system.web> <globalization culture="ja-JP" uiCulture="zh-HK" /> </system.web>

eg: DateTime dt = DateTime.ParseExact("08/21/2013", "MM/dd/yyyy", null);

ref url : http://support.microsoft.com/kb/306162/

How do I tell if an object is a Promise?

ES6:

const promise = new Promise(resolve => resolve('olá'));

console.log(promise.toString().includes('Promise')); //true

Excluding Maven dependencies

You can utilize the dependency management mechanism.

If you create entries in the <dependencyManagement> section of your pom for spring-security-web and spring-web with the desired 3.1.0 version set the managed version of the artifact will override those specified in the transitive dependency tree.

I'm not sure if that really saves you any code, but it is a cleaner solution IMO.

How to print the data in byte array as characters?

If you want to print the bytes as chars you can use the String constructor.

byte[] bytes = new byte[] { -1, -128, 1, 127 };
System.out.println(new String(bytes, 0));

PHPExcel auto size column width

This code snippet will auto size all the columns that contain data in all the sheets. There is no need to use the activeSheet getter and setter.

// In my case this line didn't make much of a difference
PHPExcel_Shared_Font::setAutoSizeMethod(PHPExcel_Shared_Font::AUTOSIZE_METHOD_EXACT);
// Iterating all the sheets
/** @var PHPExcel_Worksheet $sheet */
foreach ($objPHPExcel->getAllSheets() as $sheet) {
    // Iterating through all the columns
    // The after Z column problem is solved by using numeric columns; thanks to the columnIndexFromString method
    for ($col = 0; $col <= PHPExcel_Cell::columnIndexFromString($sheet->getHighestDataColumn()); $col++) {
        $sheet->getColumnDimensionByColumn($col)->setAutoSize(true);
    }
}

Best practices with STDIN in Ruby?

Something like this perhaps?

#/usr/bin/env ruby

if $stdin.tty?
  ARGV.each do |file|
    puts "do something with this file: #{file}"
  end
else
  $stdin.each_line do |line|
    puts "do something with this line: #{line}"
  end
end

Example:

> cat input.txt | ./myprog.rb
do something with this line: this
do something with this line: is
do something with this line: a
do something with this line: test
> ./myprog.rb < input.txt 
do something with this line: this
do something with this line: is
do something with this line: a
do something with this line: test
> ./myprog.rb arg1 arg2 arg3
do something with this file: arg1
do something with this file: arg2
do something with this file: arg3

How to stop line breaking in vim

If, like me, you're running gVim on Windows then your .vimrc file may be sourcing another 'example' Vimscript file that automatically sets textwidth (in my case to 78) for text files.

My answer to a similar question as this one – How to stop gVim wrapping text at column 80 – on the Vi and Vim Stack Exchange site:

In my case, Vitor's comment suggested I run the following:

:verbose set tw?

Doing so gave me the following output:

textwidth=78
      Last set from C:\Program Files (x86)\Vim\vim74\vimrc_example.vim

In vimrc_example.vim, I found the relevant lines:

" Only do this part when compiled with support for autocommands.
if has("autocmd")

  ...

  " For all text files set 'textwidth' to 78 characters.
  autocmd FileType text setlocal textwidth=78

  ...

And I found that my .vimrc is sourcing that file:

source $VIMRUNTIME/vimrc_example.vim

In my case, I don't want textwidth to be set for any files, so I just commented out the relevant line in vimrc_example.vim.

How to cast an object in Objective-C

((SelectionListViewController *)myEditController).list

More examples:

int i = (int)19.5f; // (precision is lost)
id someObject = [NSMutableArray new]; // you don't need to cast id explicitly

Why do I get AttributeError: 'NoneType' object has no attribute 'something'?

You can get this error with you have commented out HTML in a Flask application. Here the value for qual.date_expiry is None:

   <!-- <td>{{ qual.date_expiry.date() }}</td> -->

Delete the line or fix it up:

<td>{% if qual.date_attained != None %} {{ qual.date_attained.date() }} {% endif %} </td>

How can I make a HTML a href hyperlink open a new window?

<a href="#" onClick="window.open('http://www.yahoo.com', '_blank')">test</a>

Easy as that.

Or without JS

<a href="http://yahoo.com" target="_blank">test</a>

How to insert a text at the beginning of a file?

To insert just a newline:

sed '1i\\'

How can I use std::maps with user-defined types as key?

The right solution is to Specialize std::less for your class/Struct.

• Basically maps in cpp are implemented as Binary Search Trees.

  1. BSTs compare elements of nodes to determine the organization of the tree.
  2. Nodes who's element compares less than that of the parent node are placed on the left of the parent and nodes whose elements compare greater than the parent nodes element are placed on the right. i.e.

For each node, node.left.key < node.key < node.right.key

Every node in the BST contains Elements and in case of maps its KEY and a value, And keys are supposed to be ordered. More About Map implementation : The Map data Type.

In case of cpp maps , keys are the elements of the nodes and values does not take part in the organization of the tree its just a supplementary data .

So It means keys should be compatible with std::less or operator< so that they can be organized. Please check map parameters.

Else if you are using user defined data type as keys then need to give meaning full comparison semantics for that data type.

Solution : Specialize std::less:

The third parameter in map template is optional and it is std::less which will delegate to operator< ,

So create a new std::less for your user defined data type. Now this new std::less will be picked by std::map by default.

namespace std
{
    template<> struct  less<MyClass>
    {
        bool operator() (const MyClass& lhs, const MyClass& rhs) const
        {
            return lhs.anyMemen < rhs.age;
        }
    };

}

Note: You need to create specialized std::less for every user defined data type(if you want to use that data type as key for cpp maps).

Bad Solution: Overloading operator< for your user defined data type. This solution will also work but its very bad as operator < will be overloaded universally for your data type/class. which is undesirable in client scenarios.

Please check answer Pavel Minaev's answer

What is the reason for java.lang.IllegalArgumentException: No enum const class even though iterating through values() works just fine?

Instead of defining: COLUMN_HEADINGS("columnHeadings")

Try defining it as: COLUMNHEADINGS("columnHeadings")

Then when you call getByName(String name) method, call it with the upper-cased String like this: getByName(myStringVariable.toUpperCase())

I had the same problem as you, and this worked for me.

Get a file name from a path

For long time I was looking for a function able to properly decompose file path. For me this code is working perfectly for both Linux and Windows.

void decomposePath(const char *filePath, char *fileDir, char *fileName, char *fileExt)
{
    #if defined _WIN32
        const char *lastSeparator = strrchr(filePath, '\\');
    #else
        const char *lastSeparator = strrchr(filePath, '/');
    #endif

    const char *lastDot = strrchr(filePath, '.');
    const char *endOfPath = filePath + strlen(filePath);
    const char *startOfName = lastSeparator ? lastSeparator + 1 : filePath;
    const char *startOfExt = lastDot > startOfName ? lastDot : endOfPath;

    if(fileDir)
        _snprintf(fileDir, MAX_PATH, "%.*s", startOfName - filePath, filePath);

    if(fileName)
        _snprintf(fileName, MAX_PATH, "%.*s", startOfExt - startOfName, startOfName);

    if(fileExt)
        _snprintf(fileExt, MAX_PATH, "%s", startOfExt);
}

Example results are:

[]
  fileDir:  ''
  fileName: ''
  fileExt:  ''

[.htaccess]
  fileDir:  ''
  fileName: '.htaccess'
  fileExt:  ''

[a.exe]
  fileDir:  ''
  fileName: 'a'
  fileExt:  '.exe'

[a\b.c]
  fileDir:  'a\'
  fileName: 'b'
  fileExt:  '.c'

[git-archive]
  fileDir:  ''
  fileName: 'git-archive'
  fileExt:  ''

[git-archive.exe]
  fileDir:  ''
  fileName: 'git-archive'
  fileExt:  '.exe'

[D:\Git\mingw64\libexec\git-core\.htaccess]
  fileDir:  'D:\Git\mingw64\libexec\git-core\'
  fileName: '.htaccess'
  fileExt:  ''

[D:\Git\mingw64\libexec\git-core\a.exe]
  fileDir:  'D:\Git\mingw64\libexec\git-core\'
  fileName: 'a'
  fileExt:  '.exe'

[D:\Git\mingw64\libexec\git-core\git-archive.exe]
  fileDir:  'D:\Git\mingw64\libexec\git-core\'
  fileName: 'git-archive'
  fileExt:  '.exe'

[D:\Git\mingw64\libexec\git.core\git-archive.exe]
  fileDir:  'D:\Git\mingw64\libexec\git.core\'
  fileName: 'git-archive'
  fileExt:  '.exe'

[D:\Git\mingw64\libexec\git-core\git-archiveexe]
  fileDir:  'D:\Git\mingw64\libexec\git-core\'
  fileName: 'git-archiveexe'
  fileExt:  ''

[D:\Git\mingw64\libexec\git.core\git-archiveexe]
  fileDir:  'D:\Git\mingw64\libexec\git.core\'
  fileName: 'git-archiveexe'
  fileExt:  ''

I hope this helps you also :)

How do I grep recursively?

In my IBM AIX Server (OS version: AIX 5.2), use:

find ./ -type f -print -exec grep -n -i "stringYouWannaFind" {} \; 

this will print out path/file name and relative line number in the file like:

./inc/xxxx_x.h

2865: /** Description : stringYouWannaFind */

anyway,it works for me : )

Python IndentationError: unexpected indent

Check if you mixed tabs and spaces, that is a frequent source of indentation errors.

Why do we have to specify FromBody and FromUri?

Just addition to above answers ..

[FromUri] can also be used to bind complex types from uri parameters instead of passing parameters from querystring

For Ex..

public class GeoPoint
{
    public double Latitude { get; set; } 
    public double Longitude { get; set; }
}

[RoutePrefix("api/Values")]
public ValuesController : ApiController
{
    [Route("{Latitude}/{Longitude}")]
    public HttpResponseMessage Get([FromUri] GeoPoint location) { ... }
}

Can be called like:

http://localhost/api/values/47.678558/-122.130989

How do I force a vertical scrollbar to appear?

html { overflow-y: scroll; }

This css rule causes a vertical scrollbar to always appear.

Source: http://css-tricks.com/snippets/css/force-vertical-scrollbar/

How to redirect in a servlet filter?

Your response object is declared as a ServletResponse. To use the sendRedirect() method, you have to cast it to HttpServletResponse. This is an extended interface that adds methods related to the HTTP protocol.

Cassandra port usage - how are the ports used?

For Apache Cassandra 2.0 you need to take into account the following TCP ports: (See EC2 security group configuration and Apache Cassandra FAQ)

Cassandra

  • 7199 JMX monitoring port
  • 1024 - 65355 Random port required by JMX. Starting with Java 7u4 a specific port can be specified using the com.sun.management.jmxremote.rmi.port property.
  • 7000 Inter-node cluster
  • 7001 SSL inter-node cluster
  • 9042 CQL Native Transport Port
  • 9160 Thrift

DataStax OpsCenter

  • 61620 opscenterd daemon
  • 61621 Agent
  • 8888 Website

Architecture

A possible architecture with Cassandra + OpsCenter on EC2 could look like this: AWS EC2 with OpsCenter

Cannot find Dumpbin.exe

You can use the Visual Studio command prompt. dumpbin is available then.

How do I minimize the command prompt from my bat file

There is a quite interesting way to execute script minimized by making him restart itself minimised. Here is the code to put in the beginning of your script:

if not DEFINED IS_MINIMIZED set IS_MINIMIZED=1 && start "" /min "%~dpnx0" %* && exit
... script logic here ...
exit

How it works

When the script is being executed IS_MINIMIZED is not defined (if not DEFINED IS_MINIMIZED) so:

  1. IS_MINIMIZED is set to 1: set IS_MINIMIZED=1.
  2. Script starts a copy of itself using start command && start "" /min "%~dpnx0" %* where:

    1. "" - empty title for the window.
    2. /min - switch to run minimized.
    3. "%~dpnx0" - full path to your script.
    4. %* - passing through all your script's parameters.
  3. Then initial script finishes its work: && exit.

For the started copy of the script variable IS_MINIMIZED is set by the original script so it just skips the execution of the first line and goes directly to the script logic.

Remarks

  • You have to reserve some variable name to use it as a flag.
  • The script should be ended with exit, otherwise the cmd window wouldn't be closed after the script execution.
  • If your script doesn't accept arguments you could use argument as a flag instead of variable:

    if "%1" == "" start "" /min "%~dpnx0" MY_FLAG && exit or shorter if "%1" == "" start "" /min "%~f0" MY_FLAG && exit

How I can print to stderr in C?

Do you know sprintf? It's basically the same thing with fprintf. The first argument is the destination (the file in the case of fprintf i.e. stderr), the second argument is the format string, and the rest are the arguments as usual.

I also recommend this printf (and family) reference.

how to draw smooth curve through N points using javascript HTML5 canvas?

If you want to determine the equation of the curve through n points then the following code will give you the coefficients of the polynomial of degree n-1 and save these coefficients to the coefficients[] array (starting from the constant term). The x coordinates do not have to be in order. This is an example of a Lagrange polynomial.

var xPoints=[2,4,3,6,7,10]; //example coordinates
var yPoints=[2,5,-2,0,2,8];
var coefficients=[];
for (var m=0; m<xPoints.length; m++) coefficients[m]=0;
    for (var m=0; m<xPoints.length; m++) {
        var newCoefficients=[];
        for (var nc=0; nc<xPoints.length; nc++) newCoefficients[nc]=0;
        if (m>0) {
            newCoefficients[0]=-xPoints[0]/(xPoints[m]-xPoints[0]);
            newCoefficients[1]=1/(xPoints[m]-xPoints[0]);
    } else {
        newCoefficients[0]=-xPoints[1]/(xPoints[m]-xPoints[1]);
        newCoefficients[1]=1/(xPoints[m]-xPoints[1]);
    }
    var startIndex=1; 
    if (m==0) startIndex=2; 
    for (var n=startIndex; n<xPoints.length; n++) {
        if (m==n) continue;
        for (var nc=xPoints.length-1; nc>=1; nc--) {
        newCoefficients[nc]=newCoefficients[nc]*(-xPoints[n]/(xPoints[m]-xPoints[n]))+newCoefficients[nc-1]/(xPoints[m]-xPoints[n]);
        }
        newCoefficients[0]=newCoefficients[0]*(-xPoints[n]/(xPoints[m]-xPoints[n]));
    }    
    for (var nc=0; nc<xPoints.length; nc++) coefficients[nc]+=yPoints[m]*newCoefficients[nc];
}

Get height of div with no height set in css

Can do this in jQuery. Try all options .height(), .innerHeight() or .outerHeight().

$('document').ready(function() {
    $('#right_div').css({'height': $('#left_div').innerHeight()});
});

Example Screenshot

enter image description here

Hope this helps. Thanks!!

Event handlers for Twitter Bootstrap dropdowns?

Twitter bootstrap is meant to give a baseline functionality, and provides only basic javascript plugins that do something on screen. Any additional content or functionality, you'll have to do yourself.

<div class="btn-group">
  <button class="btn dropdown-toggle" data-toggle="dropdown">Action <span class="caret"></span></button>
  <ul class="dropdown-menu">
    <li><a href="#" id="action-1">Action</a></li>
    <li><a href="#" id="action-2">Another action</a></li>
    <li><a href="#" id="action-3">Something else here</a></li>
  </ul>
</div><!-- /btn-group -->

and then with jQuery

jQuery("#action-1").click(function(e){
//do something
e.preventDefault();
});

Proper way to make HTML nested list?

Option 2 is correct.

The nested list should be inside a <li> element of the list in which it is nested.

Link to the W3C Wiki on Lists (taken from comment below): HTML Lists Wiki.

Link to the HTML5 W3C ul spec: HTML5 ul. Note that a ul element may contain exactly zero or more li elements. The same applies to HTML5 ol. The description list (HTML5 dl) is similar, but allows both dt and dd elements.

More Notes:

  • dl = definition list.
  • ol = ordered list (numbers).
  • ul = unordered list (bullets).

How to change context root of a dynamic web project in Eclipse?

I just wanted to add that if you don't want your application name in the root context at all, you and just put "/" (no quotes, just the forward slash) in the Eclipse --> Web Project Settings --> Context Root entry

That will deploy the webapp to just http://localhost:8080/

Of course, this will cause problems with other webapps you try to run on the server, so heads up with that.

Took me forever to piece that together... so even though this post is 8 years old, hopefully this will still help someone!

Static method in a generic class?

When you specify a generic type for your class, JVM know about it only having an instance of your class, not definition. Each definition has only parametrized type.

Generics work like templates in C++, so you should first instantiate your class, then use the function with the type being specified.

Bulk Insert into Oracle database: Which is better: FOR Cursor loop or a simple Select?

I would recommend the Select option because cursors take longer.
Also using the Select is much easier to understand for anyone who has to modify your query

Pandas split column of lists into multiple columns

Here's another solution using df.transform and df.set_index:

>>> (df['teams']
       .transform([lambda x:x[0], lambda x:x[1]])
       .set_axis(['team1','team2'],
                  axis=1,
                  inplace=False)
    )

  team1 team2
0    SF   NYG
1    SF   NYG
2    SF   NYG
3    SF   NYG
4    SF   NYG
5    SF   NYG
6    SF   NYG

ld: framework not found Pods

You're more than likely trying to get the pods to work into you project right? The only way to do so is by creating a separate project that uses CocoaPods.

Close all work-spaces that you are using.

Next, make sure you have your Podfile completely ready to go.

In the command line, wherever your file is, type the command:

pod deintegrate

Then, install your pod agian.

pod install or pod update

Now you can use your project's new workspace to develop from. Look for a file called .workspace. Use that file!

Here is a guide on using CocoaPods

How to replace � in a string

Use the unicode escape sequence. First you'll have to find the codepoint for the character you seek to replace (let's just say it is ABCD in hex):

str = str.replaceAll("\uABCD", "");

Two values from one input in python?

I tried this in Python 3 , seems to work fine .

a, b = map(int,input().split())

print(a)

print(b)

Input : 3 44

Output :

3

44

Installing OpenCV for Python on Ubuntu, getting ImportError: No module named cv2.cv

If you want as simple as possible, install from the repository:

sudo apt-get install python-opencv libopencv-dev python-numpy python-dev

Get Root Directory Path of a PHP project

When you say that

$_SERVER['DOCUMENT_ROOT']

contains this path:

D:/workspace

Then D: is what you are looking for, isn't it? In that case you could explode the string by slashes and return the first one:

$pathInPieces = explode('/', $_SERVER['DOCUMENT_ROOT']);
echo $pathInPieces[0];

This will output the server's root directory.

Update: When you use the constant DIRECTORY_SEPARATOR instead of the hardcoded slash ('/') this code is also working under Windows.

Update 2: The $_SERVER global variable is not always available. On command line (cli) for example. So you should use __DIR__ instead of $_SERVER['DOCUMENT_ROOT']. __DIR__ returns the path of the php file itself.

How can I see all the "special" characters permissible in a varchar or char field in SQL Server?

i think that special characters are # and @ only... query will list both.

DECLARE  @str VARCHAR(50) 
SET @str = '[azAB09ram#reddy@wer45' + CHAR(5) + 'a~b$' 
SELECT DISTINCT poschar 
FROM   MASTER..spt_values S 
       CROSS APPLY (SELECT SUBSTRING(@str,NUMBER,1) AS poschar) t 
WHERE  NUMBER > 0 
       AND NUMBER <= LEN(@str) 
       AND NOT (ASCII(t.poschar) BETWEEN 65 AND 90 
                 OR ASCII(t.poschar) BETWEEN 97 AND 122 
                 OR ASCII(t.poschar) BETWEEN 48 AND 57) 

onchange event on input type=range is not triggering in firefox while dragging

UPDATE: I am leaving this answer here as an example of how to use mouse events to use range/slider interactions in desktop (but not mobile) browsers. However, I have now also written a completely different and, I believe, better answer elsewhere on this page that uses a different approach to providing a cross-browser desktop-and-mobile solution to this problem.

Original answer:

Summary: A cross-browser, plain JavaScript (i.e. no-jQuery) solution to allow reading range input values without using on('input'... and/or on('change'... which work inconsistently between browsers.

As of today (late Feb, 2016), there is still browser inconsistency so I'm providing a new work-around here.

The problem: When using a range input, i.e. a slider, on('input'... provides continuously updated range values in Mac and Windows Firefox, Chrome and Opera as well as Mac Safari, while on('change'... only reports the range value upon mouse-up. In contrast, in Internet Explorer (v11), on('input'... does not work at all, and on('change'... is continuously updated.

I report here 2 strategies to get identical continuous range value reporting in all browsers using vanilla JavaScript (i.e. no jQuery) by using the mousedown, mousemove and (possibly) mouseup events.

Strategy 1: Shorter but less efficient

If you prefer shorter code over more efficient code, you can use this 1st solution which uses mousesdown and mousemove but not mouseup. This reads the slider as needed, but continues firing unnecessarily during any mouse-over events, even when the user has not clicked and is thus not dragging the slider. It essentially reads the range value both after 'mousedown' and during 'mousemove' events, slightly delaying each using requestAnimationFrame.

_x000D_
_x000D_
var rng = document.querySelector("input");_x000D_
_x000D_
read("mousedown");_x000D_
read("mousemove");_x000D_
read("keydown"); // include this to also allow keyboard control_x000D_
_x000D_
function read(evtType) {_x000D_
  rng.addEventListener(evtType, function() {_x000D_
    window.requestAnimationFrame(function () {_x000D_
      document.querySelector("div").innerHTML = rng.value;_x000D_
      rng.setAttribute("aria-valuenow", rng.value); // include for accessibility_x000D_
    });_x000D_
  });_x000D_
}
_x000D_
<div>50</div><input type="range"/>
_x000D_
_x000D_
_x000D_

Strategy 2: Longer but more efficient

If you need more efficient code and can tolerate longer code length, then you can use the following solution which uses mousedown, mousemove and mouseup. This also reads the slider as needed, but appropriately stops reading it as soon as the mouse button is released. The essential difference is that is only starts listening for 'mousemove' after 'mousedown', and it stops listening for 'mousemove' after 'mouseup'.

_x000D_
_x000D_
var rng = document.querySelector("input");_x000D_
_x000D_
var listener = function() {_x000D_
  window.requestAnimationFrame(function() {_x000D_
    document.querySelector("div").innerHTML = rng.value;_x000D_
  });_x000D_
};_x000D_
_x000D_
rng.addEventListener("mousedown", function() {_x000D_
  listener();_x000D_
  rng.addEventListener("mousemove", listener);_x000D_
});_x000D_
rng.addEventListener("mouseup", function() {_x000D_
  rng.removeEventListener("mousemove", listener);_x000D_
});_x000D_
_x000D_
// include the following line to maintain accessibility_x000D_
// by allowing the listener to also be fired for_x000D_
// appropriate keyboard events_x000D_
rng.addEventListener("keydown", listener);
_x000D_
<div>50</div><input type="range"/>
_x000D_
_x000D_
_x000D_

Demo: Fuller explanation of the need for, and implementation of, the above work-arounds

The following code more fully demonstrates numerous aspects of this strategy. Explanations are embedded in the demonstration:

_x000D_
_x000D_
var select, inp, listen, unlisten, anim, show, onInp, onChg, onDn1, onDn2, onMv1, onMv2, onUp, onMvCombo1, onDnCombo1, onUpCombo2, onMvCombo2, onDnCombo2;_x000D_
_x000D_
select   = function(selctr)     { return document.querySelector(selctr);      };_x000D_
inp = select("input");_x000D_
listen   = function(evtTyp, cb) { return inp.   addEventListener(evtTyp, cb); };_x000D_
unlisten = function(evtTyp, cb) { return inp.removeEventListener(evtTyp, cb); };_x000D_
anim     = function(cb)         { return window.requestAnimationFrame(cb);    };_x000D_
show = function(id) {_x000D_
 return function() {_x000D_
    select("#" + id + " td~td~td"   ).innerHTML = inp.value;_x000D_
    select("#" + id + " td~td~td~td").innerHTML = (Math.random() * 1e20).toString(36); // random text_x000D_
  };_x000D_
};_x000D_
_x000D_
onInp      =                  show("inp" )                                      ;_x000D_
onChg      =                  show("chg" )                                      ;_x000D_
onDn1      =                  show("mdn1")                                      ;_x000D_
onDn2      = function() {anim(show("mdn2"));                                   };_x000D_
onMv1      =                  show("mmv1")                                      ;_x000D_
onMv2      = function() {anim(show("mmv2"));                                   };_x000D_
onUp       =                  show("mup" )                                      ;_x000D_
onMvCombo1 = function() {anim(show("cmb1"));                                   };_x000D_
onDnCombo1 = function() {anim(show("cmb1"));   listen("mousemove", onMvCombo1);};_x000D_
onUpCombo2 = function() {                    unlisten("mousemove", onMvCombo2);};_x000D_
onMvCombo2 = function() {anim(show("cmb2"));                                   };_x000D_
onDnCombo2 = function() {anim(show("cmb2"));   listen("mousemove", onMvCombo2);};_x000D_
_x000D_
listen("input"    , onInp     );_x000D_
listen("change"   , onChg     );_x000D_
listen("mousedown", onDn1     );_x000D_
listen("mousedown", onDn2     );_x000D_
listen("mousemove", onMv1     );_x000D_
listen("mousemove", onMv2     );_x000D_
listen("mouseup"  , onUp      );_x000D_
listen("mousedown", onDnCombo1);_x000D_
listen("mousedown", onDnCombo2);_x000D_
listen("mouseup"  , onUpCombo2);
_x000D_
table {border-collapse: collapse; font: 10pt Courier;}_x000D_
th, td {border: solid black 1px; padding: 0 0.5em;}_x000D_
input {margin: 2em;}_x000D_
li {padding-bottom: 1em;}
_x000D_
<p>Click on 'Full page' to see the demonstration properly.</p>_x000D_
<table>_x000D_
  <tr><th></th><th>event</th><th>range value</th><th>random update indicator</th></tr>_x000D_
  <tr id="inp" ><td>A</td><td>input                                </td><td>100</td><td>-</td></tr>_x000D_
  <tr id="chg" ><td>B</td><td>change                               </td><td>100</td><td>-</td></tr>_x000D_
  <tr id="mdn1"><td>C</td><td>mousedown                            </td><td>100</td><td>-</td></tr>_x000D_
  <tr id="mdn2"><td>D</td><td>mousedown using requestAnimationFrame</td><td>100</td><td>-</td></tr>_x000D_
  <tr id="mmv1"><td>E</td><td>mousemove                            </td><td>100</td><td>-</td></tr>_x000D_
  <tr id="mmv2"><td>F</td><td>mousemove using requestAnimationFrame</td><td>100</td><td>-</td></tr>_x000D_
  <tr id="mup" ><td>G</td><td>mouseup                              </td><td>100</td><td>-</td></tr>_x000D_
  <tr id="cmb1"><td>H</td><td>mousedown/move combo                 </td><td>100</td><td>-</td></tr>_x000D_
  <tr id="cmb2"><td>I</td><td>mousedown/move/up combo              </td><td>100</td><td>-</td></tr>_x000D_
</table>_x000D_
<input type="range" min="100" max="999" value="100"/>_x000D_
<ol>_x000D_
  <li>The 'range value' column shows the value of the 'value' attribute of the range-type input, i.e. the slider. The 'random update indicator' column shows random text as an indicator of whether events are being actively fired and handled.</li>_x000D_
  <li>To see browser differences between input and change event implementations, use the slider in different browsers and compare A and&nbsp;B.</li>_x000D_
  <li>To see the importance of 'requestAnimationFrame' on 'mousedown', click a new location on the slider and compare C&nbsp;(incorrect) and D&nbsp;(correct).</li>_x000D_
  <li>To see the importance of 'requestAnimationFrame' on 'mousemove', click and drag but do not release the slider, and compare E&nbsp;(often 1&nbsp;pixel behind) and F&nbsp;(correct).</li>_x000D_
  <li>To see why an initial mousedown is required (i.e. to see why mousemove alone is insufficient), click and hold but do not drag the slider and compare E&nbsp;(incorrect), F&nbsp;(incorrect) and H&nbsp;(correct).</li>_x000D_
  <li>To see how the mouse event combinations can provide a work-around for continuous update of a range-type input, use the slider in any manner and note whichever of A or B continuously updates the range value in your current browser. Then, while still using the slider, note that H and I provide the same continuously updated range value readings as A or B.</li>_x000D_
  <li>To see how the mouseup event reduces unnecessary calculations in the work-around, use the slider in any manner and compare H and&nbsp;I. They both provide correct range value readings. However, then ensure the mouse is released (i.e. not clicked) and move it over the slider without clicking and notice the ongoing updates in the third table column for H but not&nbsp;I.</li>_x000D_
</ol>
_x000D_
_x000D_
_x000D_

Qt jpg image display

#include ...

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QGraphicsScene scene;
    QGraphicsView view(&scene);
    QGraphicsPixmapItem item(QPixmap("c:\\test.png"));
    scene.addItem(&item);
    view.show();
    return a.exec();
}

This should work. :) List of supported formats can be found here

What is an efficient way to implement a singleton pattern in Java?

Depending on the usage, there are several "correct" answers.

Since Java 5, the best way to do it is to use an enum:

public enum Foo {
   INSTANCE;
}

Pre Java 5, the most simple case is:

public final class Foo {

    private static final Foo INSTANCE = new Foo();

    private Foo() {
        if (INSTANCE != null) {
            throw new IllegalStateException("Already instantiated");
        }
    }

    public static Foo getInstance() {
        return INSTANCE;
    }

    public Object clone() throws CloneNotSupportedException{
        throw new CloneNotSupportedException("Cannot clone instance of this class");
    }
}

Let's go over the code. First, you want the class to be final. In this case, I've used the final keyword to let the users know it is final. Then you need to make the constructor private to prevent users to create their own Foo. Throwing an exception from the constructor prevents users to use reflection to create a second Foo. Then you create a private static final Foo field to hold the only instance, and a public static Foo getInstance() method to return it. The Java specification makes sure that the constructor is only called when the class is first used.

When you have a very large object or heavy construction code and also have other accessible static methods or fields that might be used before an instance is needed, then and only then you need to use lazy initialization.

You can use a private static class to load the instance. The code would then look like:

public final class Foo {

    private static class FooLoader {
        private static final Foo INSTANCE = new Foo();
    }

    private Foo() {
        if (FooLoader.INSTANCE != null) {
            throw new IllegalStateException("Already instantiated");
        }
    }

    public static Foo getInstance() {
        return FooLoader.INSTANCE;
    }
}

Since the line private static final Foo INSTANCE = new Foo(); is only executed when the class FooLoader is actually used, this takes care of the lazy instantiation, and is it guaranteed to be thread safe.

When you also want to be able to serialize your object you need to make sure that deserialization won't create a copy.

public final class Foo implements Serializable {

    private static final long serialVersionUID = 1L;

    private static class FooLoader {
        private static final Foo INSTANCE = new Foo();
    }

    private Foo() {
        if (FooLoader.INSTANCE != null) {
            throw new IllegalStateException("Already instantiated");
        }
    }

    public static Foo getInstance() {
        return FooLoader.INSTANCE;
    }

    @SuppressWarnings("unused")
    private Foo readResolve() {
        return FooLoader.INSTANCE;
    }
}

The method readResolve() will make sure the only instance will be returned, even when the object was serialized in a previous run of your program.

Delete all objects in a list

If the goal is to delete the objects a and b themselves (which appears to be the case), forming the list [a, b] is not helpful. Instead, one should keep a list of strings used as the names of those objects. These allow one to delete the objects in a loop, by accessing the globals() dictionary.

c = ['a', 'b']
# create and work with a and b    
for i in c:
    del globals()[i]

How to use && in EL boolean expressions in Facelets?

In addition to the answer of BalusC, use the following Java RegExp to replace && with and:

Search:  (#\{[^\}]*)(&&)([^\}]*\})
Replace: $1and$3

You have run this regular expression replacement multiple times to find all occurences in case you are using >2 literals in your EL expressions. Mind to replace the leading # by $ if your EL expression syntax differs.

Need to get a string after a "word" in a string in c#

Simpler way (if your only keyword is "code" ) may be:

string ErrorCode = yourString.Split(new string[]{"code"}, StringSplitOptions.None).Last();

Using Java 8 to convert a list of objects into a string obtained from the toString() method

With Java 8+

String s = Arrays.toString(list.stream().toArray(AClass[]::new));

Not the most efficient, but it is a solution with a small amount of code.

How to run a script as root on Mac OS X?

sudo ./scriptname

sudo bash will basically switch you over to running a shell as root, although it's probably best to stay as su as little as possible.

How to get all count of mongoose model?

You should give an object as argument

userModel.count({name: "sam"});

or

userModel.count({name: "sam"}).exec(); //if you are using promise

or

userModel.count({}); // if you want to get all counts irrespective of the fields

On the recent version of mongoose, count() is deprecated so use

userModel.countDocuments({name: "sam"});

jQuery - how can I find the element with a certain id?

This

var verificaHorario = $("#tbIntervalos").find("#" + horaInicial);

will find you the td that needs to be blocked.

Actually this will also do:

var verificaHorario = $("#" + horaInicial);

Testing for the size() of the wrapped set will answer your question regarding the existence of the id.

Sending command line arguments to npm script

jakub.g's answer is correct, however an example using grunt seems a bit complex.

So my simpler answer:

- Sending a command line argument to an npm script

Syntax for sending command line arguments to an npm script:

npm run [command] [-- <args>]

Imagine we have an npm start task in our package.json to kick off webpack dev server:

"scripts": {
  "start": "webpack-dev-server --port 5000"
},

We run this from the command line with npm start

Now if we want to pass in a port to the npm script:

"scripts": {
  "start": "webpack-dev-server --port process.env.port || 8080"
},

running this and passing the port e.g. 5000 via command line would be as follows:

npm start --port:5000

- Using package.json config:

As mentioned by jakub.g, you can alternatively set params in the config of your package.json

"config": {
  "myPort": "5000"
}

"scripts": {
  "start": "webpack-dev-server --port process.env.npm_package_config_myPort || 8080"
},

npm start will use the port specified in your config, or alternatively you can override it

npm config set myPackage:myPort 3000

- Setting a param in your npm script

An example of reading a variable set in your npm script. In this example NODE_ENV

"scripts": {
  "start:prod": "NODE_ENV=prod node server.js",
  "start:dev": "NODE_ENV=dev node server.js"
},

read NODE_ENV in server.js either prod or dev

var env = process.env.NODE_ENV || 'prod'

if(env === 'dev'){
    var app = require("./serverDev.js");
} else {
    var app = require("./serverProd.js");
}

Git: Pull from other remote

git pull is really just a shorthand for git pull <remote> <branchname>, in most cases it's equivalent to git pull origin master. You will need to add another remote and pull explicitly from it. This page describes it in detail:

http://help.github.com/forking/

Saving timestamp in mysql table using php

Use datetime field type. It comes with many advantages like human readability (nobody reads timestamps) and MySQL functions.

To convert from a unix timestamp, you can use MySQL function FROM_UNIXTIME(1299762201428). To convert back you can use UNIX_TIMESTAMP: SELECT UNIX_TIMESTAMP(t_time) FROM table_name.

Of course, if you don't like MySQL function, you could always use PHP: 'INSERT INTO table_name SET t_time = ' . date('Y-m-d H:i:s', $unix_timestamp).

move div with CSS transition

transition-property:width;

This should work. you have to have browser dependent code

How to chain scope queries with OR instead of AND?

In case anyone is looking for an updated answer to this one, it looks like there is an existing pull request to get this into Rails: https://github.com/rails/rails/pull/9052.

Thanks to @j-mcnally's monkey patch for ActiveRecord (https://gist.github.com/j-mcnally/250eaaceef234dd8971b) you can do the following:

Person.where(name: 'John').or.where(last_name: 'Smith').all

Even more valuable is the ability to chain scopes with OR:

scope :first_or_last_name, ->(name) { where(name: name.split(' ').first).or.where(last_name: name.split(' ').last) }
scope :parent_last_name, ->(name) { includes(:parents).where(last_name: name) }

Then you can find all Persons with first or last name or whose parent with last name

Person.first_or_last_name('John Smith').or.parent_last_name('Smith')

Not the best example for the use of this, but just trying to fit it with the question.

How to open html file?

I encountered this problem today as well. I am using Windows and the system language by default is Chinese. Hence, someone may encounter this Unicode error similarly. Simply add encoding = 'utf-8':

with open("test.html", "r", encoding='utf-8') as f:
    text= f.read()

Use different Python version with virtualenv

For Mac(High Sierra), install the virtualenv on python3 and create a virtualenv for python2:

 $ python3 -m pip install virtualenv
 $ python3 -m virtualenv --python=python2 vp27
 $ source vp27/bin/activate
 (vp27)$ python --version
 Python 2.7.14

find: missing argument to -exec

Both {} and && will cause problems due to being expanded by the command line. I would suggest trying:

find /home/me/download/ -type f -name "*.rm" -exec ffmpeg -i \{} -sameq \{}.mp3 \; -exec rm \{} \;

Node.js Logging

You can also use npmlog by issacs, recommended in https://npmjs.org/doc/coding-style.html.

You can find this module here https://github.com/isaacs/npmlog

ExpressionChangedAfterItHasBeenCheckedError: Expression has changed after it was checked. Previous value: 'undefined'

setTimeout(() => { // your code here }, 0);

I wrapped my code in setTimeout and it worked

How to initialize log4j properly?

If we are using apache commons logging wrapper on top of log4j, then we need to have both the jars available in classpath. Also, commons-logging.properties and log4j.properties/xml should be available in classpath.

We can also pass implementation class and log4j.properties name as JAVA_OPTS either using -Dorg.apache.commons.logging.Log=<logging implementation class name> -Dlog4j.configuration=<file:location of log4j.properties/xml file>. Same can be done via setting JAVA_OPTS in case of app/web server.

It will help to externalize properties which can be changed in deployment.

How to tell if a connection is dead in python

If I'm not mistaken this is usually handled via a timeout.

Programmatically open new pages on Tabs

This may work if you can call a batch file (I use php with XP sp2 and IE8... you can try IE7, dunno). Use the following (or similar) in your .bat file to open Windows: Start ""C:\Progra~1\Intern~1\iexplore "http://www.site.com". There is no space between the quotation mark and C:\Progr... etc. At some point, this may begin to open new windows (i.e., target="_blank") rather than new tabs, but works up to a point; not extensively tested. To use this in a regular batch file (CMD.exe), you probably need to have a window already open. Just sharing something I stumbled across. EDITED for clarification.

Postgresql tables exists, but getting "relation does not exist" when querying

I had to include double quotes with the table name.

db=> \d
                           List of relations
 Schema |                     Name                      | Type  | Owner 
--------+-----------------------------------------------+-------+-------
 public | COMMONDATA_NWCG_AGENCIES                      | table | dan
 ...

db=> \d COMMONDATA_NWCG_AGENCIES
Did not find any relation named "COMMONDATA_NWCG_AGENCIES".

???

Double quotes:

db=> \d "COMMONDATA_NWCG_AGENCIES"
                         Table "public.COMMONDATA_NWCG_AGENCIES"
          Column          |            Type             | Collation | Nullable | Default 
--------------------------+-----------------------------+-----------+----------+---------
 ID                       | integer                     |           | not null | 
 ...

Lots and lots of double quotes:

db=> select ID from COMMONDATA_NWCG_AGENCIES limit 1;
ERROR:  relation "commondata_nwcg_agencies" does not exist
LINE 1: select ID from COMMONDATA_NWCG_AGENCIES limit 1;
                       ^
db=> select ID from "COMMONDATA_NWCG_AGENCIES" limit 1;
ERROR:  column "id" does not exist
LINE 1: select ID from "COMMONDATA_NWCG_AGENCIES" limit 1;
               ^
db=> select "ID" from "COMMONDATA_NWCG_AGENCIES" limit 1;
 ID 
----
  1
(1 row)

This is postgres 11. The CREATE TABLE statements from this dump had double quotes as well:

DROP TABLE IF EXISTS "COMMONDATA_NWCG_AGENCIES";

CREATE TABLE "COMMONDATA_NWCG_AGENCIES" (
...

How to fade changing background image

Someone pointed me to this thread because I had this same issue but it didn't work for me. After hours of searching I found a solution using this - https://github.com/rewish/jquery-bgswitcher#readme

It has a few other options other than fade too.

Creating a div element in jQuery

d = document.createElement('div');
$(d).addClass(classname)
    .html(text)
    .appendTo($("#myDiv")) //main div
.click(function () {
    $(this).remove();
})
    .hide()
    .slideToggle(300)
    .delay(2500)
    .slideToggle(300)
    .queue(function () {
    $(this).remove();
});

How to change port for jenkins window service when 8080 is being used

Use Default Port

If the default port 8080 has been bind with other process, Then kill that process.

DOS> netstat -a -o -n

Find the process id (PID) XXXX of the process which occupied 8080.

DOS> taskkill /F /PID XXXX

Now, start Jenkins (on default port)

DOS> Java -jar jenkins.war

Use Custom Port

DOS> Java -jar jenkins.war --httpPort=8008

How do you show animated GIFs on a Windows Form (c#)

It's not too hard.

  1. Drop a picturebox onto your form.
  2. Add the .gif file as the image in the picturebox
  3. Show the picturebox when you are loading.

Things to take into consideration:

  • Disabling the picturebox will prevent the gif from being animated.

Animated gifs:

If you are looking for animated gifs you can generate them:

AjaxLoad - Ajax Loading gif generator

Another way of doing it:

Another way that I have found that works quite well is the async dialog control that I found on the code project

Why can't I reference System.ComponentModel.DataAnnotations?

If you don't have it in references (like I did not) you can also add the NuGet System.ComponentModel.Annotations to get the assemblies and resolve the errors. (Adding it here as this answer still top of Google for the error)

Bootstrap 3 Navbar with Logo

Please try following code:

<style>
   .navbar a.navbar-brand {padding: 9px 15px 8px; }
</style>
<a class="navbar-brand" href="#">
   <img src="http://placehold.it/140x34/000000/ffffff/&amp;text=LOGO" alt="">
</a>

jquery - How to determine if a div changes its height or any css attribute?

Please don't use techniques described in other answers here. They are either not working with css3 animations size changes, floating layout changes or changes that don't come from jQuery land. You can use a resize-detector, a event-based approach, that doesn't waste your CPU time.

https://github.com/marcj/css-element-queries

It contains a ResizeSensor class you can use for that purpose.

new ResizeSensor(jQuery('#mainContent'), function(){ 
    console.log('main content dimension changed');
});

Disclaimer: I wrote this library

jQuery: set selected value of dropdown list?

You can select dropdown option value by name

jQuery("#option_id").find("option:contains('Monday')").each(function()
{
 if( jQuery(this).text() == 'Monday' )
 {
  jQuery(this).attr("selected","selected");
  }
});

How to style SVG with external CSS?

A very quick solution to have dynamic style with an external css stylesheet, in case you are using the <object> tag to embed your svg.

This example will add a class to the root <svg> tag on click on a parent element.

file.svg :

<?xml-stylesheet type="text/css" href="../svg.css"?>
 <svg xmlns="http://www.w3.org/2000/svg" viewBox="">
  <g>
   <path/>
  </g>
 </svg>

html :

<a class="parent">
  <object data="file.svg"></object>
</a>

Jquery :

$(function() {
  $(document).on('click', '.parent', function(){
    $(this).find('object').contents().find('svg').attr("class","selected");
  }
});

on click parent element :

 <svg xmlns="http://www.w3.org/2000/svg" viewBox="" class="selected">

then you can manage your css

svg.css :

path {
 fill:none;
 stroke:#000;
 stroke-miterlimit:1.41;
 stroke-width:0.7px;
}

.selected path {
 fill:none;
 stroke:rgb(64, 136, 209);
 stroke-miterlimit:1.41;
 stroke-width:0.7px;
}

How to force browser to download file?

You are setting the response headers after writing the contents of the file to the output stream. This is quite late in the response lifecycle to be setting headers. The correct sequence of operations should be to set the headers first, and then write the contents of the file to the servlet's outputstream.

Therefore, your method should be written as follows (this won't compile as it is a mere representation):

response.setContentType("application/force-download");
response.setContentLength((int)f.length());
        //response.setContentLength(-1);
response.setHeader("Content-Transfer-Encoding", "binary");
response.setHeader("Content-Disposition","attachment; filename=\"" + "xxx\"");//fileName);
...
...
File f= new File(fileName);

InputStream in = new FileInputStream(f);
BufferedInputStream bin = new BufferedInputStream(in);
DataInputStream din = new DataInputStream(bin);

while(din.available() > 0){
    out.print(din.readLine());
    out.print("\n");
}

The reason for the failure is that it is possible for the actual headers sent by the servlet would be different from what you are intending to send. After all, if the servlet container does not know what headers (which appear before the body in the HTTP response), then it may set appropriate headers to ensure that the response is valid; setting the headers after the file has been written is therefore futile and redundant as the container might have already set the headers. You could confirm this by looking at the network traffic using Wireshark or a HTTP debugging proxy like Fiddler or WebScarab.

You may also refer to the Java EE API documentation for ServletResponse.setContentType to understand this behavior:

Sets the content type of the response being sent to the client, if the response has not been committed yet. The given content type may include a character encoding specification, for example, text/html;charset=UTF-8. The response's character encoding is only set from the given content type if this method is called before getWriter is called.

This method may be called repeatedly to change content type and character encoding. This method has no effect if called after the response has been committed.

...

Is a Java hashmap search really O(1)?

Academics aside, from a practical perspective, HashMaps should be accepted as having an inconsequential performance impact (unless your profiler tells you otherwise.)

No resource found that matches the given name '@style/ Theme.Holo.Light.DarkActionBar'

Make sure you've set your target API (different from the target SDK) in the Project Properties (not the manifest) to be at least 4.0/API 14.

The property 'value' does not exist on value of type 'HTMLElement'

A quick fix for this is use [ ] to select the attribute.

function greet(elementId) {
    var inputValue = document.getElementById(elementId)["value"];
    if(inputValue.trim() == "") {
        inputValue = "World";
    }
    document.getElementById("greet").innerText = greeter(inputValue);
}

I just try few methods and find out this solution,
I don't know what's the problem behind your original script.

For reference you may refer to Tomasz Nurkiewicz's post.

Match groups in Python

Starting Python 3.8, and the introduction of assignment expressions (PEP 572) (:= operator), we can now capture the condition value re.search(pattern, statement) in a variable (let's all it match) in order to both check if it's not None and then re-use it within the body of the condition:

if match := re.search('I love (\w+)', statement):
  print(f'He loves {match.group(1)}')
elif match := re.search("Ich liebe (\w+)", statement):
  print(f'Er liebt {match.group(1)}')
elif match := re.search("Je t'aime (\w+)", statement):
  print(f'Il aime {match.group(1)}')

Manage toolbar's navigation and back button from fragment in android

OnToolBar there is a navigation icon at left side

Toolbar  toolbar = (Toolbar) findViewById(R.id.tool_bar);
        toolbar.setTitle(getResources().getString(R.string.title_activity_select_event));
        setSupportActionBar(toolbar);

        getSupportActionBar().setDisplayShowHomeEnabled(true);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

By using this at left side navigation icon appear and on navigation icon click it call parent activity.

and in manifest we can notify system about parent activity.

  <activity
            android:name=".CategoryCloudSelectActivity"
            android:parentActivityName=".EventSelectionActivity"
            android:screenOrientation="portrait" />

Java: Reading integers from a file into an array

You might want to do something like this (if you're in java 5 & up)

Scanner scanner = new Scanner(new File("tall.txt"));
int [] tall = new int [100];
int i = 0;
while(scanner.hasNextInt()){
   tall[i++] = scanner.nextInt();
}

Merge two (or more) lists into one, in C# .NET

When you got few list but you don't know how many exactly, use this:

listsOfProducts contains few lists filled with objects.

List<Product> productListMerged = new List<Product>();

listsOfProducts.ForEach(q => q.ForEach(e => productListMerged.Add(e)));

VS 2017 Git Local Commit DB.lock error on every commit

  1. .vs folder should not be committed.
  2. create a file with name ".gitignore" inside the projects git root directory.
  3. Add the following line ".vs/" in ".gitignore" file.
  4. Now commit your project.

enter image description here

How to remove a virtualenv created by "pipenv run"

You can run the pipenv command with the --rm option as in:

pipenv --rm

This will remove the virtualenv created for you under ~/.virtualenvs

See https://pipenv.kennethreitz.org/en/latest/cli/#cmdoption-pipenv-rm

How can I plot with 2 different y-axes?

I too suggests, twoord.stackplot() in the plotrix package plots with more of two ordinate axes.

data<-read.table(text=
"e0AL fxAL e0CO fxCO e0BR fxBR anos
 51.8  5.9 50.6  6.8 51.0  6.2 1955
 54.7  5.9 55.2  6.8 53.5  6.2 1960
 57.1  6.0 57.9  6.8 55.9  6.2 1965
 59.1  5.6 60.1  6.2 57.9  5.4 1970
 61.2  5.1 61.8  5.0 59.8  4.7 1975
 63.4  4.5 64.0  4.3 61.8  4.3 1980
 65.4  3.9 66.9  3.7 63.5  3.8 1985
 67.3  3.4 68.0  3.2 65.5  3.1 1990
 69.1  3.0 68.7  3.0 67.5  2.6 1995
 70.9  2.8 70.3  2.8 69.5  2.5 2000
 72.4  2.5 71.7  2.6 71.1  2.3 2005
 73.3  2.3 72.9  2.5 72.1  1.9 2010
 74.3  2.2 73.8  2.4 73.2  1.8 2015
 75.2  2.0 74.6  2.3 74.2  1.7 2020
 76.0  2.0 75.4  2.2 75.2  1.6 2025
 76.8  1.9 76.2  2.1 76.1  1.6 2030
 77.6  1.9 76.9  2.1 77.1  1.6 2035
 78.4  1.9 77.6  2.0 77.9  1.7 2040
 79.1  1.8 78.3  1.9 78.7  1.7 2045
 79.8  1.8 79.0  1.9 79.5  1.7 2050
 80.5  1.8 79.7  1.9 80.3  1.7 2055
 81.1  1.8 80.3  1.8 80.9  1.8 2060
 81.7  1.8 80.9  1.8 81.6  1.8 2065
 82.3  1.8 81.4  1.8 82.2  1.8 2070
 82.8  1.8 82.0  1.7 82.8  1.8 2075
 83.3  1.8 82.5  1.7 83.4  1.9 2080
 83.8  1.8 83.0  1.7 83.9  1.9 2085
 84.3  1.9 83.5  1.8 84.4  1.9 2090
 84.7  1.9 83.9  1.8 84.9  1.9 2095
 85.1  1.9 84.3  1.8 85.4  1.9 2100", header=T)

require(plotrix)
twoord.stackplot(lx=data$anos, rx=data$anos, 
                 ldata=cbind(data$e0AL, data$e0BR, data$e0CO),
                 rdata=cbind(data$fxAL, data$fxBR, data$fxCO),
                 lcol=c("black","red", "blue"),
                 rcol=c("black","red", "blue"), 
                 ltype=c("l","o","b"),
                 rtype=c("l","o","b"), 
                 lylab="Años de Vida", rylab="Hijos x Mujer", 
                 xlab="Tiempo",
                 main="Mortalidad/Fecundidad:1950–2100",
                 border="grey80")
legend("bottomright", c(paste("Proy:", 
                      c("A. Latina", "Brasil", "Colombia"))), cex=1,
        col=c("black","red", "blue"), lwd=2, bty="n",  
        lty=c(1,1,2), pch=c(NA,1,1) )

What precisely does 'Run as administrator' do?

The Run as *Anything command saves you from logging out and logging in as the user for which you use the runas command for.

The reason programs ask for this elevated privilege started with Black Comb and the Panther folder. There is 0 access to the Kernel in windows unless through the Admin prompt and then it is only a virtual relation with the O/S kernel.

Hoorah!

APT command line interface-like yes/no input?

Here's my take on it, I simply wanted to abort if the user did not affirm the action.

import distutils

if unsafe_case:
    print('Proceed with potentially unsafe thing? [y/n]')
    while True:
        try:
            verify = distutils.util.strtobool(raw_input())
            if not verify:
                raise SystemExit  # Abort on user reject
            break
        except ValueError as err:
            print('Please enter \'yes\' or \'no\'')
            # Try again
    print('Continuing ...')
do_unsafe_thing()

Clearing _POST array fully

To unset the $_POST variable, redeclare it as an empty array:

$_POST = array();

Send data through routing paths in Angular

Best I found on internet for this is ngx-navigation-with-data. It is very simple and good for navigation the data from one component to another component. You have to just import the component class and use it in very simple way. Suppose you have home and about component and want to send data then

HOME COMPONENT

import { Component, OnInit } from '@angular/core';
import { NgxNavigationWithDataComponent } from 'ngx-navigation-with-data';

@Component({
 selector: 'app-home',
 templateUrl: './home.component.html',
 styleUrls: ['./home.component.css']
})
export class HomeComponent implements OnInit {

constructor(public navCtrl: NgxNavigationWithDataComponent) { }

 ngOnInit() {
 }

 navigateToABout() {
  this.navCtrl.navigate('about', {name:"virendta"});
 }

}

ABOUT COMPONENT

import { Component, OnInit } from '@angular/core';
import { NgxNavigationWithDataComponent } from 'ngx-navigation-with-data';

@Component({
 selector: 'app-about',
 templateUrl: './about.component.html',
 styleUrls: ['./about.component.css']
})
export class AboutComponent implements OnInit {

 constructor(public navCtrl: NgxNavigationWithDataComponent) {
  console.log(this.navCtrl.get('name')); // it will console Virendra
  console.log(this.navCtrl.data); // it will console whole data object here
 }

 ngOnInit() {
 }

}

For any query follow https://www.npmjs.com/package/ngx-navigation-with-data

Comment down for help.

Initializing select with AngularJS and ng-repeat

For the select tag, angular provides the ng-options directive. It gives you the specific framework to set up options and set a default. Here is the updated fiddle using ng-options that works as expected: http://jsfiddle.net/FxM3B/4/

Updated HTML (code stays the same)

<body ng-app ng-controller="AppCtrl">
<div>Operator is: {{filterCondition.operator}}</div>
<select ng-model="filterCondition.operator" ng-options="operator.value as operator.displayName for operator in operators">
</select>
</body>

How can I suppress column header output for a single SQL statement?

Invoke mysql with the -N (the alias for -N is --skip-column-names) option:

mysql -N ...
use testdb;
select * from names;

+------+-------+
|    1 | pete  |
|    2 | john  |
|    3 | mike  |
+------+-------+
3 rows in set (0.00 sec)

Credit to ErichBSchulz for pointing out the -N alias.

To remove the grid (the vertical and horizontal lines) around the results use -s (--silent). Columns are separated with a TAB character.

mysql -s ...
use testdb;
select * from names;

id  name
1   pete
2   john
3   mike

To output the data with no headers and no grid just use both -s and -N.

mysql -sN ...

Bootstrap 4: Multilevel Dropdown Inside Navigation

I found this multidrop-down menu which work great in all device.

Also, have hover style

It supports multi-level submenus with bootstrap 4.

_x000D_
_x000D_
$( document ).ready( function () {_x000D_
    $( '.navbar a.dropdown-toggle' ).on( 'click', function ( e ) {_x000D_
        var $el = $( this );_x000D_
        var $parent = $( this ).offsetParent( ".dropdown-menu" );_x000D_
        $( this ).parent( "li" ).toggleClass( 'show' );_x000D_
_x000D_
        if ( !$parent.parent().hasClass( 'navbar-nav' ) ) {_x000D_
            $el.next().css( { "top": $el[0].offsetTop, "left": $parent.outerWidth() - 4 } );_x000D_
        }_x000D_
        $( '.navbar-nav li.show' ).not( $( this ).parents( "li" ) ).removeClass( "show" );_x000D_
        return false;_x000D_
    } );_x000D_
} );
_x000D_
.navbar-light .navbar-nav .nav-link {_x000D_
    color: rgb(64, 64, 64);_x000D_
}_x000D_
.btco-menu li > a {_x000D_
    padding: 10px 15px;_x000D_
    color: #000;_x000D_
}_x000D_
_x000D_
.btco-menu .active a:focus,_x000D_
.btco-menu li a:focus ,_x000D_
.navbar > .show > a:focus{_x000D_
    background: transparent;_x000D_
    outline: 0;_x000D_
}_x000D_
_x000D_
.dropdown-menu .show > .dropdown-toggle::after{_x000D_
    transform: rotate(-90deg);_x000D_
}
_x000D_
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css" integrity="sha384-rwoIResjU2yc3z8GV/NPeZWAv56rSmLldC3R/AZzGRnGxQQKnKkoFVhFQhNUwEyJ" crossorigin="anonymous">_x000D_
_x000D_
<script src="https://code.jquery.com/jquery-3.1.1.slim.min.js" integrity="sha384-A7FZj7v+d/sdmMqp/nOQwliLvUsJfDHW+k9Omg/a/EheAdgtzNs3hpfag6Ed950n" crossorigin="anonymous"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/tether/1.4.0/js/tether.min.js" integrity="sha384-DztdAPBWPRXSA/3eYEEUWrWCy7G5KFbe8fFjk5JAIxUYHKkDx6Qin1DkWx51bBrb" crossorigin="anonymous"></script>_x000D_
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/js/bootstrap.min.js" integrity="sha384-vBWWzlZJ8ea9aCX4pEW3rVHjgjt7zpkNpZk+02D9phzyeVkE+jo0ieGizqPLForn" crossorigin="anonymous"></script>_x000D_
_x000D_
<nav class="navbar navbar-toggleable-md navbar-light bg-faded btco-menu">_x000D_
    <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">_x000D_
        <span class="navbar-toggler-icon"></span>_x000D_
    </button>_x000D_
    <a class="navbar-brand" href="#">Navbar</a>_x000D_
    <div class="collapse navbar-collapse" id="navbarNavDropdown">_x000D_
        <ul class="navbar-nav">_x000D_
            <li class="nav-item active">_x000D_
                <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>_x000D_
            </li>_x000D_
            <li class="nav-item">_x000D_
                <a class="nav-link" href="#">Features</a>_x000D_
            </li>_x000D_
            <li class="nav-item">_x000D_
                <a class="nav-link" href="#">Pricing</a>_x000D_
            </li>_x000D_
            <li class="nav-item dropdown">_x000D_
                <a class="nav-link dropdown-toggle" href="https://bootstrapthemes.co" id="navbarDropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Dropdown link</a>_x000D_
                <ul class="dropdown-menu" aria-labelledby="navbarDropdownMenuLink">_x000D_
                    <li><a class="dropdown-item" href="#">Action</a></li>_x000D_
                    <li><a class="dropdown-item" href="#">Another action</a></li>_x000D_
                    <li><a class="dropdown-item dropdown-toggle" href="#">Submenu</a>_x000D_
                        <ul class="dropdown-menu">_x000D_
                            <li><a class="dropdown-item" href="#">Submenu action</a></li>_x000D_
                            <li><a class="dropdown-item" href="#">Another submenu action</a></li>_x000D_
_x000D_
                            <li><a class="dropdown-item dropdown-toggle" href="#">Subsubmenu</a>_x000D_
                                <ul class="dropdown-menu">_x000D_
                                    <li><a class="dropdown-item" href="#">Subsubmenu action</a></li>_x000D_
                                    <li><a class="dropdown-item" href="#">Another subsubmenu action</a></li>_x000D_
                                </ul>_x000D_
                            </li>_x000D_
                            <li><a class="dropdown-item dropdown-toggle" href="#">Second subsubmenu</a>_x000D_
                                <ul class="dropdown-menu">_x000D_
                                    <li><a class="dropdown-item" href="#">Subsubmenu action</a></li>_x000D_
                                    <li><a class="dropdown-item" href="#">Another subsubmenu action</a></li>_x000D_
                                </ul>_x000D_
                            </li>_x000D_
                        </ul>_x000D_
                    </li>_x000D_
                </ul>_x000D_
            </li>_x000D_
        </ul>_x000D_
    </div>_x000D_
</nav>
_x000D_
_x000D_
_x000D_

How to remove elements from a generic list while iterating over it?

As any remove is taken on a condition you can use

list.RemoveAll(item => item.Value == someValue);

PHP Check for NULL

How about using

if (empty($result['column']))

org.hibernate.MappingException: Unknown entity

My issue was resolved After adding
sessionFactory.setPackagesToScan( new String[] { "com.springhibernate.model" }); Tested this Functionality in spring boot latest version 2.1.2.

Full Method:

 @Bean( name="sessionFactoryConfig")
    public LocalSessionFactoryBean sessionFactoryConfig() {

        LocalSessionFactoryBean sessionFactory = new LocalSessionFactoryBean();

        sessionFactory.setDataSource(dataSourceConfig());
        sessionFactory.setPackagesToScan(
                new String[] { "com.springhibernate.model" });

        sessionFactory.setHibernateProperties(hibernatePropertiesConfig());

        return sessionFactory;
    }

Sorting a DropDownList? - C#, ASP.NET

What kind of object are you using for databinding? Typically I use Collection<T>, List<T>, or Queue<T> (depending on circumstances). These are relatively easy to sort using a custom delegate. See MSDN documentation on the Comparison(T) delegate.

python pandas: Remove duplicates by columns A, keeping the row with the highest value in column B

Easiest way to do this:

# First you need to sort this DF as Column A as ascending and column B as descending 
# Then you can drop the duplicate values in A column 
# Optional - you can reset the index and get the nice data frame again
# I'm going to show you all in one step. 

d = {'A': [1,1,2,3,1,2,3,1], 'B': [30, 40,50,42,38,30,25,32]}
df = pd.DataFrame(data=d)
df

    A   B
0   1   30
1   1   40
2   2   50
3   3   42
4   1   38
5   2   30
6   3   25
7   1   32


df = df.sort_values(['A','B'], ascending =[True,False]).drop_duplicates(['A']).reset_index(drop=True)

df

    A   B
0   1   40
1   2   50
2   3   42

Add column to SQL Server

Use this query:

ALTER TABLE tablename ADD columname DATATYPE(size);

And here is an example:

ALTER TABLE Customer ADD LastName VARCHAR(50);

How to convert a selection to lowercase or uppercase in Sublime Text

As a bonus for setting up a Title Case shortcut key Ctrl+kt (while holding Ctrl, press k and t), go to Preferences --> Keybindings-User

If you have a blank file open and close with the square brackets:

[  { "keys": ["ctrl+k", "ctrl+t"], "command": "title_case" } ]

Otherwise if you already have stuff in there, just make sure if it comes after another command to prepend a comma "," and add:

{ "keys": ["ctrl+k", "ctrl+t"], "command": "title_case" }

Rename master branch for both local and remote Git repositories

The following can be saved to the shell script to do the job:

For example:

remote="origin"

if [ "$#" -eq 0 ] # if there are no arguments, just quit
then
    echo "Usage: $0 oldName newName or $0 newName" >&2
    exit 1
elif
    [ "$#" -eq 1 ] # if only one argument is given, rename current branch
then 
    oldBranchName="$(git branch | grep \* | cut -d ' ' -f2)" #save current branch name
    newBranchName=$1
else
    oldBranchName=$1
    newBranchName=$2
fi

git branch -m $oldBranchName $newBranchName

git push $remote :$oldBranchName #delete old branch on remote
git push --set-upstream $remote $newBranchName # add new branch name on remote and track it

Please note that here default remote name "origin" is hard-coded, you can extend the script to make if configurable!

Then this script can be used with bash aliases, git aliases or in, for example, sourcetree custom actions.

Can't pickle <type 'instancemethod'> when using multiprocessing Pool.map()

A potentially trivial solution to this is to switch to using multiprocessing.dummy. This is a thread based implementation of the multiprocessing interface that doesn't seem to have this problem in Python 2.7. I don't have a lot of experience here, but this quick import change allowed me to call apply_async on a class method.

A few good resources on multiprocessing.dummy:

https://docs.python.org/2/library/multiprocessing.html#module-multiprocessing.dummy

http://chriskiehl.com/article/parallelism-in-one-line/

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException

i don't see any for loop to initalize the variables.you can do something like this.

for(i=0;i<50;i++){
 /* Code which is necessary with a simple if statement*/

   }

Change status bar color with AppCompat ActionBarActivity

Applying

    <item name="android:statusBarColor">@color/color_primary_dark</item>
<item name="android:windowDrawsSystemBarBackgrounds">true</item>

in Theme.AppCompat.Light.DarkActionBar didn't worked for me. What did the trick is , giving colorPrimaryDark as usual along with android:colorPrimary in styles.xml

<item name="android:colorAccent">@color/color_primary</item>
<item name="android:colorPrimary">@color/color_primary</item>
<item name="android:colorPrimaryDark">@color/color_primary_dark</item>

and in setting

if (Build.VERSION.SdkInt >= BuildVersionCodes.Lollipop)
                {
                    Window window = this.Window;
                    Window.AddFlags(WindowManagerFlags.DrawsSystemBarBackgrounds);
                }

didn't had to set statusbar color in code .

Run chrome in fullscreen mode on Windows

I would like to share my way of starting chrome - specificaly youtube tv - in full screen mode automatically, without the need of pressing F11. kiosk/fullscreen options doesn't seem to work (Version 41.0.2272.89). It has some steps though...

  • Start chrome and navigate to page (www.youtube.com/tv)
  • Drag the address from the address bar (the lock icon) to the desktop. It will create a shortcut.
  • From chrome, open Apps (the icon with the multiple coloured dots)
  • From desktop, drag the shortcut into the Apps space
  • Right click on the new icon in Apps and select "Open fullscreen"
  • Right click again on the icon in Apps and select "Create shortcuts..."
  • Select for example Desktop and Create. A new shortcut will be created on desktop.

Now, whenever you click on this shortcut, chrome will start in fullscreen and at the page you defined. I guess you can put this shortcut in startup folder to run when windows starts, but I haven't tried it.

How to check if number is divisible by a certain number?

n % x == 0

Means that n can be divided by x. So... for instance, in your case:

boolean isDivisibleBy20 = number % 20 == 0;

Also, if you want to check whether a number is even or odd (whether it is divisible by 2 or not), you can use a bitwise operator:

boolean even = (number & 1) == 0;
boolean odd  = (number & 1) != 0;

php_network_getaddresses: getaddrinfo failed: Name or service not known

You cannot open a connection directly to a path on a remote host using fsockopen. The url www.mydomain.net/1/file.php contains a path, when the only valid value for that first parameter is the host, www.mydomain.net.

If you are trying to access a remote URL, then file_get_contents() is your best bet. You can provide a full URL to that function, and it will fetch the content at that location using a normal HTTP request.

If you only want to send an HTTP request and ignore the response, you could use fsockopen() and manually send the HTTP request headers, ignoring any response. It might be easier with cURL though, or just plain old fopen(), which will open the connection but not necessarily read any response. If you wanted to do it with fsockopen(), it might look something like this:

$fp = fsockopen("www.mydomain.net", 80, $errno, $errstr, 30);
fputs($fp, "GET /1/file.php HTTP/1.1\n");
fputs($fp, "Host: www.mydomain.net\n");
fputs($fp, "Connection: close\n\n"); 

That leaves any error handling up to you of course, but it would mean that you wouldn't waste time reading the response.

Corrupted Access .accdb file: "Unrecognized Database Format"

Sometimes it might depend on whether you are using code to access the database or not. If you are using "DriverJet" in your code instead of "DriverACE" (or an older version of the DAO library) such a problem is highly probable to happen. You just need to replace "DriverJet" with "DriverACE" and test.

Exception : javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated

You can get this if the client specifies "https" but the server is only running "http". So, the server isn't expecting to make a secure connection.

How to load my app from Eclipse to my Android phone instead of AVD

I had the same problem, and have not been able to get Eclipse in Windows 7 to recognise the device. The device is correctly configured, Windows 7 recognises it on the USB port, and I edited the Run settings in Eclipse to prompt for a device, and it is just not there.

I ran it with the following steps:

  • Connect the device to the computer with USB.
  • Ensure the device is not locked (ie. timed out in the UI). I have to keep unlocking it while I'm working.
  • Wait for Windows to recognise the USB device, and when the autoplay menu comes up select Open device to view files. It should open up the file system in the device, in Explorer.
  • In Explorer go to the Eclipse workspace and find the apk file from the build (eg. MyFirstApp.apk)
  • Copy the apk file to the Downloads directory on the device
  • On the device, use the My Files app (or similar) to open the Downloads directory.
  • Click the downloaded file (My First App.apk) and Android offers to install it
  • Select install
  • The app is now in the installed Apps. Run it.

A second method is to mail the apk file to the device and then download and install it. (Credits to a post on SO which I can't find now).

A third method is to use DropBox. This requires installation of DropBox on the PC and on the device (from the play store) but once both are set up it runs very smoothly. Just share a DropBox folder between the two devices, and then drop the APK into that folder on the PC, and open it on the device. With this method you don't need a USB connection, and can also install the APK on multiple devices. It also assists the management of multiple development versions (by making a separate sub-folder for each version).

Regex expressions in Java, \\s vs. \\s+

The first regex will match one whitespace character. The second regex will reluctantly match one or more whitespace characters. For most purposes, these two regexes are very similar, except in the second case, the regex can match more of the string, if it prevents the regex match from failing.  from http://www.coderanch.com/t/570917/java/java/regex-difference

Remove duplicate rows in MySQL

A really easy way to do this is to add a UNIQUE index on the 3 columns. When you write the ALTER statement, include the IGNORE keyword. Like so:

ALTER IGNORE TABLE jobs
ADD UNIQUE INDEX idx_name (site_id, title, company);

This will drop all the duplicate rows. As an added benefit, future INSERTs that are duplicates will error out. As always, you may want to take a backup before running something like this...

How do I compile with -Xlint:unchecked?

There is another way for gradle:

compileJava {
    options.compilerArgs << "-Xlint:unchecked" << "-Xlint:deprecation"
}

How to resume Fragment from BackStack if exists

Easier solution will be changing this line

ft.replace(R.id.content_frame, A); to ft.add(R.id.content_frame, A);

And inside your XML layout please use

  android:background="@color/white"
  android:clickable="true"
  android:focusable="true"

Clickable means that it can be clicked by a pointer device or be tapped by a touch device.

Focusable means that it can gain the focus from an input device like a keyboard. Input devices like keyboards cannot decide which view to send its input events to based on the inputs itself, so they send them to the view that has focus.

Print in Landscape format

you cannot set this in javascript, you have to do this with html/css:

<style type="text/css" media="print">
  @page { size: landscape; }
</style>

EDIT: See this Question and the accepted answer for more information on browser support: Is @Page { size:landscape} obsolete?

Can I Set "android:layout_below" at Runtime Programmatically?

Alternatively you can use the views current layout parameters and modify them:

RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) viewToLayout.getLayoutParams();
params.addRule(RelativeLayout.BELOW, R.id.below_id);

Difference between attr_accessor and attr_accessible

A quick & concise difference overview :

attr_accessor is an easy way to create read and write accessors in your class. It is used when you do not have a column in your database, but still want to show a field in your forms. This field is a “virtual attribute” in a Rails model.

virtual attribute – an attribute not corresponding to a column in the database.

attr_accessible is used to identify attributes that are accessible by your controller methods makes a property available for mass-assignment.. It will only allow access to the attributes that you specify, denying the rest.

In Tensorflow, get the names of all the Tensors in a graph

Previous answers are good, I'd just like to share a utility function I wrote to select Tensors from a graph:

def get_graph_op(graph, and_conds=None, op='and', or_conds=None):
    """Selects nodes' names in the graph if:
    - The name contains all items in and_conds
    - OR/AND depending on op
    - The name contains any item in or_conds

    Condition starting with a "!" are negated.
    Returns all ops if no optional arguments is given.

    Args:
        graph (tf.Graph): The graph containing sought tensors
        and_conds (list(str)), optional): Defaults to None.
            "and" conditions
        op (str, optional): Defaults to 'and'. 
            How to link the and_conds and or_conds:
            with an 'and' or an 'or'
        or_conds (list(str), optional): Defaults to None.
            "or conditions"

    Returns:
        list(str): list of relevant tensor names
    """
    assert op in {'and', 'or'}

    if and_conds is None:
        and_conds = ['']
    if or_conds is None:
        or_conds = ['']

    node_names = [n.name for n in graph.as_graph_def().node]

    ands = {
        n for n in node_names
        if all(
            cond in n if '!' not in cond
            else cond[1:] not in n
            for cond in and_conds
        )}

    ors = {
        n for n in node_names
        if any(
            cond in n if '!' not in cond
            else cond[1:] not in n
            for cond in or_conds
        )}

    if op == 'and':
        return [
            n for n in node_names
            if n in ands.intersection(ors)
        ]
    elif op == 'or':
        return [
            n for n in node_names
            if n in ands.union(ors)
        ]

So if you have a graph with ops:

['model/classifier/dense/kernel',
'model/classifier/dense/kernel/Assign',
'model/classifier/dense/kernel/read',
'model/classifier/dense/bias',
'model/classifier/dense/bias/Assign',
'model/classifier/dense/bias/read',
'model/classifier/dense/MatMul',
'model/classifier/dense/BiasAdd',
'model/classifier/ArgMax/dimension',
'model/classifier/ArgMax']

Then running

get_graph_op(tf.get_default_graph(), ['dense', '!kernel'], 'or', ['Assign'])

returns:

['model/classifier/dense/kernel/Assign',
'model/classifier/dense/bias',
'model/classifier/dense/bias/Assign',
'model/classifier/dense/bias/read',
'model/classifier/dense/MatMul',
'model/classifier/dense/BiasAdd']

The module was expected to contain an assembly manifest

I found another strange reason and i thought maybe another developer confused as me. I did run install.bat that created to install my service in developer Command Prompt of VS2010 but my service generated in VS2012. it was going to this error and drives me to crazy but i try VS2012 Developer Command Prompt tools and everything gone to be OK. I don't no why but my problem was solved. so you can test it and if anyone know reason of that please share with us. Thanks.

Remove the last three characters from a string

myString.Remove(myString.Length-3);

Convert hex string to int in Python

Or ast.literal_eval (this is safe, unlike eval):

ast.literal_eval("0xffff")

Demo:

>>> import ast
>>> ast.literal_eval("0xffff")
65535
>>> 

HttpWebRequest using Basic authentication

You can also just add the authorization header yourself.

Just make the name "Authorization" and the value "Basic BASE64({USERNAME:PASSWORD})"

String username = "abc";
String password = "123";
String encoded = System.Convert.ToBase64String(System.Text.Encoding.GetEncoding("ISO-8859-1").GetBytes(username + ":" + password));
httpWebRequest.Headers.Add("Authorization", "Basic " + encoded);

Edit

Switched the encoding from UTF-8 to ISO 8859-1 per What encoding should I use for HTTP Basic Authentication? and Jeroen's comment.

SELECT * FROM X WHERE id IN (...) with Dapper ORM

If your IN clause is too big for MSSQL to handle, you can use a TableValueParameter with Dapper pretty easily.

  1. Create your TVP type in MSSQL:

    CREATE TYPE [dbo].[MyTVP] AS TABLE([ProviderId] [int] NOT NULL)
    
  2. Create a DataTable with the same column(s) as the TVP and populate it with values

    var tvpTable = new DataTable();
    tvpTable.Columns.Add(new DataColumn("ProviderId", typeof(int)));
    // fill the data table however you wish
    
  3. Modify your Dapper query to do an INNER JOIN on the TVP table:

    var query = @"SELECT * FROM Providers P
        INNER JOIN @tvp t ON p.ProviderId = t.ProviderId";
    
  4. Pass the DataTable in your Dapper query call

    sqlConn.Query(query, new {tvp = tvpTable.AsTableValuedParameter("dbo.MyTVP")});
    

This also works fantastically when you want to do a mass update of multiple columns - simply build a TVP and do an UPDATE with an inner join to the TVP.

Can't install nuget package because of "Failed to initialize the PowerShell host"

You need to open PM console( Tools > Nuget Package Manager > Package Manager Console), it will prompt you if you want to run nuget manager as untrusted , type 'A' and click enter that will resolve the issue.

What is this Javascript "require"?

You know how when you are running JavaScript in the browser, you have access to variables like "window" or Math? You do not have to declare these variables, they have been written for you to use whenever you want.

Well, when you are running a file in the Node.js environment, there is a variable that you can use. It is called "module" It is an object. It has a property called "exports." And it works like this:

In a file that we will name example.js, you write:

example.js

module.exports = "some code";

Now, you want this string "some code" in another file.

We will name the other file otherFile.js

In this file, you write:

otherFile.js

let str = require('./example.js')

That require() statement goes to the file that you put inside of it, finds whatever data is stored on the module.exports property. The let str = ... part of your code means that whatever that require statement returns is stored to the str variable.

So, in this example, the end-result is that in otherFile.js you now have this:

let string = "some code";

  • or -

let str = ('./example.js').module.exports

Note:

the file-name that is written inside of the require statement: If it is a local file, it should be the file-path to example.js. Also, the .js extension is added by default, so I didn't have to write it.

You do something similar when requiring node.js libraries, such as Express. In the express.js file, there is an object named 'module', with a property named 'exports'.

So, it looks something like along these lines, under the hood (I am somewhat of a beginner so some of these details might not be exact, but it's to show the concept:

express.js

module.exports = function() {
    //It returns an object with all of the server methods
    return {
        listen: function(port){},
        get: function(route, function(req, res){}){}
     }
}

If you are requiring a module, it looks like this: const moduleName = require("module-name");

If you are requiring a local file, it looks like this: const localFile = require("./path/to/local-file");

(notice the ./ at the beginning of the file name)


Also note that by default, the export is an object .. eg module.exports = {} So, you can write module.exports.myfunction = () => {} before assigning a value to the module.exports. But you can also replace the object by writing module.exports = "I am not an object anymore."

ASP.NET MVC3 Razor - Html.ActionLink style

VB sample:

 @Html.ActionLink("Home", "Index", Nothing, New With {.style = "font-weight:bold;", .class = "someClass"})

Sample Css:

.someClass
{
    color: Green !important;
}

In my case, I found that I need the !important attribute to over ride the site.css a:link css class

How do you make a div tag into a link

If you're using HTML5, as pointed in this other question, you can put your div inside a:

<a href="http://www.google.com"><div>Some content here</div></a>

Preffer this method as it makes clear in your structure that all the content is clickable, and where it's pointing.

Eclipse: Enable autocomplete / content assist

For auto-completion triggers in Eclipse like IntelliJ, follow these steps,

  1. Go to the Eclipse Windows menu -> Preferences -> Java -> Editor -> Content assist and check your settings here
  2. Enter in Autocomplete activation string for java: abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ._@
  3. Apply and Close the Dialog box.

Thanks.

Cache an HTTP 'Get' service response in AngularJS?

I think there's an even easier way now. This enables basic caching for all $http requests (which $resource inherits):

 var app = angular.module('myApp',[])
      .config(['$httpProvider', function ($httpProvider) {
            // enable http caching
           $httpProvider.defaults.cache = true;
      }])

How to make button look like a link?

If you don't mind using twitter bootstrap I suggest you simply use the link class.

_x000D_
_x000D_
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" integrity="sha384-WskhaSGFgHYWDcbwN70/dfYBj47jz9qbsMId/iRN3ewGhXQFZCSftd1LZCfmhktB" crossorigin="anonymous">_x000D_
<button type="button" class="btn btn-link">Link</button>
_x000D_
_x000D_
_x000D_

I hope this helps somebody :) Have a nice day!

How to wait for the 'end' of 'resize' event and only then perform an action?

Here is VERY simple script to trigger both a 'resizestart' and 'resizeend' event on the window object.

There is no need to muck around with dates and times.

The d variable represents the number of milliseconds between resize events before triggering the resize end event, you can play with this to change how sensitive the end event is.

To listen to these events all you need to do is:

resizestart: $(window).on('resizestart', function(event){console.log('Resize Start!');});

resizeend: $(window).on('resizeend', function(event){console.log('Resize End!');});

(function ($) {
    var d = 250, t = null, e = null, h, r = false;

    h = function () {
        r = false;
        $(window).trigger('resizeend', e);
    };

    $(window).on('resize', function (event) {
        e = event || e;
        clearTimeout(t);

        if (!r) {
            $(window).trigger('resizestart', e);
            r = true;
        }

        t = setTimeout(h, d);
    });
}(jQuery));

batch script - run command on each file in directory

I am doing similar thing to compile all the c files in a directory.
for iterating files in different directory try this.

set codedirectory=C:\Users\code
for /r  %codedirectory% %%i in (*.c) do 
( some GCC commands )

How to sort a Collection<T>?

I came across a similar problem. Had to sort a list of 3rd party class (objects).

List<ThirdPartyClass> tpc = getTpcList(...);

ThirdPartyClass does not implement the Java Comparable interface. I found an excellent illustration from mkyong on how to approach this problem. I had to use the Comparator approach to sorting.

//Sort ThirdPartyClass based on the value of some attribute/function
Collections.sort(tpc, Compare3rdPartyObjects.tpcComp);

where the Comparator is:

public abstract class Compare3rdPartyObjects {

public static Comparator<ThirdPartyClass> tpcComp = new Comparator<ThirdPartyClass>() {

    public int compare(ThirdPartyClass tpc1, ThirdPartyClass tpc2) {

        Integer tpc1Offset = compareUsing(tpc1);
        Integer tpc2Offset = compareUsing(tpc2);

        //ascending order
        return tpc1Offset.compareTo(tpc2Offset);

    }
};

//Fetch the attribute value that you would like to use to compare the ThirdPartyClass instances 
public static Integer compareUsing(ThirdPartyClass tpc) {

    Integer value = tpc.getValueUsingSomeFunction();
    return value;
}
}

Concatenate multiple result rows of one column into one, group by another column

You can use array_agg function for that:

SELECT "Movie",
array_to_string(array_agg(distinct "Actor"),',') AS Actor
FROM Table1
GROUP BY "Movie";

Result:

MOVIE ACTOR
A 1,2,3
B 4

See this SQLFiddle

For more See 9.18. Aggregate Functions

How do I select elements of an array given condition?

Add one detail to @J.F. Sebastian's and @Mark Mikofski's answers:
If one wants to get the corresponding indices (rather than the actual values of array), the following code will do:

For satisfying multiple (all) conditions:

select_indices = np.where( np.logical_and( x > 1, x < 5) )[0] #   1 < x <5

For satisfying multiple (or) conditions:

select_indices = np.where( np.logical_or( x < 1, x > 5 ) )[0] # x <1 or x >5

Delete files older than 3 months old in a directory using .NET

I use the following in a console app, running as a service, to get directory info from the App.Settings file. Number of days to keep the files is also configurable, multiplied by -1 for use in the AddDays() method of DateTime.Now.

static void CleanBackupFiles()
        {
            string gstrUncFolder = ConfigurationManager.AppSettings["DropFolderUNC"] + "";
            int iDelAge = Convert.ToInt32(ConfigurationManager.AppSettings["NumDaysToKeepFiles"]) * -1;
            string backupdir = string.Concat(@"\", "Backup", @"\");

            string[] files = Directory.GetFiles(string.Concat(gstrUncFolder, backupdir));


            foreach (string file in files)
            {
                FileInfo fi = new FileInfo(file);
                if (fi.CreationTime < DateTime.Now.AddDays(iDelAge))
                {
                    fi.Delete();
                }
            }

        }

How to resolve 'npm should be run outside of the node repl, in your normal shell'

enter image description here

Just open Node.js commmand promt as run as administrator

matplotlib savefig in jpeg format

You can save an image as 'png' and use the python imaging library (PIL) to convert this file to 'jpg':

import Image
import matplotlib.pyplot as plt

plt.plot(range(10))
plt.savefig('testplot.png')
Image.open('testplot.png').save('testplot.jpg','JPEG')

The original:

enter image description here

The JPEG image:

enter image description here

Named parameters in JDBC

Plain vanilla JDBC does not support named parameters.

If you are using DB2 then using DB2 classes directly:

  1. Using named parameter markers with PreparedStatement objects
  2. Using named parameter markers with CallableStatement objects

Handling a timeout error in python sockets

Here is a solution I use in one of my project.

network_utils.telnet

import socket
from timeit import default_timer as timer

def telnet(hostname, port=23, timeout=1):
    start = timer()
    connection = socket.socket()
    connection.settimeout(timeout)
    try:
        connection.connect((hostname, port))
        end = timer()
        delta = end - start
    except (socket.timeout, socket.gaierror) as error:
        logger.debug('telnet error: ', error)
        delta = None
    finally:
        connection.close()

    return {
        hostname: delta
    }

Tests

def test_telnet_is_null_when_host_unreachable(self):
    hostname = 'unreachable'

    response = network_utils.telnet(hostname)

    self.assertDictEqual(response, {'unreachable': None})

def test_telnet_give_time_when_reachable(self):
    hostname = '127.0.0.1'

    response = network_utils.telnet(hostname, port=22)

    self.assertGreater(response[hostname], 0)

Moving Git repository content to another repository preserving history

This worked to move my local repo (including history) to my remote github.com repo. After creating the new empty repo at GitHub.com I use the URL in step three below and it works great.

git clone --mirror <url_of_old_repo>
cd <name_of_old_repo>
git remote add new-origin <url_of_new_repo>
git push new-origin --mirror

I found this at: https://gist.github.com/niksumeiko/8972566

Running interactive commands in Paramiko

I'm not familiar with paramiko, but this may work:

ssh_stdin.write('input value')
ssh_stdin.flush()

For information on stdin:

http://docs.python.org/library/sys.html?highlight=stdin#sys.stdin

Add a dependency in Maven

I'll assume that you're asking how to push a dependency out to a "well-known repository," and not simply asking how to update your POM.

If yes, then this is what you want to read.

And for anyone looking to set up an internal repository server, look here (half of the problem with using Maven 2 is finding the docs)

Selecting multiple columns in a Pandas dataframe

Try to use pandas.DataFrame.get (see the documentation):

import pandas as pd
import numpy as np

dates = pd.date_range('20200102', periods=6)
df = pd.DataFrame(np.random.randn(6, 4), index=dates, columns=list('ABCD'))
df.get(['A', 'C'])

maven error: package org.junit does not exist

if you are using Eclipse watch your POM dependencies and your Eclipse buildpath dependency on junit

if you select use Junit4 eclipse create TestCase using org.junit package but your POM use by default Junit3 (junit.framework package) that is the cause, like this picture:

see JUNIT conflict

Just update your Junit dependency in your POM file to Junit4 or your Eclipse BuildPath to Junit3

Blank HTML SELECT without blank item in dropdown list

<select>
     <option value="" style="display:none;"></option>
     <option value="0">aaaa</option>
     <option value="1">bbbb</option>
  </select>

Install npm (Node.js Package Manager) on Windows (w/o using Node.js MSI)

TL;DR: Install Chocolatey, Node (and NPM)

Install Chocolatey

NOTE: You might want to copy the exact command from their install page since it might change over time.

  1. Open your standard Windows command line
  2. @powershell -NoProfile -ExecutionPolicy unrestricted -Command "(iex ((new-object net.webclient).DownloadString('https://chocolatey.org/install.ps1'))) >$null 2>&1" && SET PATH="%PATH%;%ALLUSERSPROFILE%\chocolatey\bin"
  3. Restart console
  4. Done!

Install Node (and NPM)

  1. Because Chocolatey installs a directory different from the MSI installation, go to your system configuration and delete your previous node installation (if you have one)
  2. Install Chocolatey as described above
  3. choco install nodejs

    NOTE I used nodejs. I am not even sure what node is, but having had my fair share of troubles with node already being taken by something else in other systems, I thought, nodejs would be the safer bet right away

  4. Restart your console
  5. Beware: node -v works!
    • And npm -v also works! Awesome.

After this, I was able to install firebase-tools without problems (which I was not able to do previously), so something must have gone terribly right! :)

My rather complete story the first time around

"Chocolatey installs in seconds"

If you don't care about sarcasm or lamenting engineers on a Sunday afternoon, skip ahead to the installation instructions in the TL;DR section below.

For everyone else: I want to amend this answer which recommends using (what seems to be the hottest package management solution for Windows right now): Chocolatey

It gets the job done nice and quick. However, when I gave it a first try, it took me a while to make sense of the install instructions which are kinda convoluted. The install instructions go a bit like this (complete with what went through my head while going through it):

  • NOTE:
  • NOTE:
  • NOTE:

    three big-ass NOTEs before even knowing the basics... this makes me anxious... how wrong could things go!?

  • Installing With Restricted TLS

    not even sure what TLS is... Oh it's a good friend of SSL - Shouldn't this just be the default and just work out of the box? My browser can do HTTPS, NO PROBLEM! (just kidding... I know that SSL and TSL frequently cause a lot of pain in environments that have high security needs)

  • Option 1
  • Option 2

    eeh... great... Can't I just install?

  • Installing Behind a Proxy?

    Just... no...

  • Requirements

    uh boi...

  • Why does Chocolatey install where it does by default?

    Seriously!?!

  • Before You Install

    sad
    (source: clipartbest.com)

  • Can I install with a proxy?

    again with the proxy...

  • Can I install a particular version of Chocolatey?

    just any version would be fine, thank you...

  • Can I use Windows built-in compression instead of downloading 7zip?

    7zip?! Why do you even mention this?!

  • Non-Administrative Install
  • Now that sounds great!

    • "NOTE: This option should be a last resort and is considered to be an advanced scenario."
      • Sh$%!@T.

  • Alternative Installation Options

    giddy

  • Command Line
    • "This really is the easiest method because it requires no configuration of PowerShell prior to executing it."

      And there you go!

While I really appreciate the fact that pitfalls and their possible solutions are discussed so extensively, maybe re-organizing them as such, and putting the Chocolatey installs in seconds promise to work by putting the "easiest method" first would be just awesome!

Using sed to mass rename files

The sed command

s/\(.\).\(.*\)/mv & \1\2/

means to replace:

\(.\).\(.*\)

with:

mv & \1\2

just like a regular sed command. However, the parentheses, & and \n markers change it a little.

The search string matches (and remembers as pattern 1) the single character at the start, followed by a single character, follwed by the rest of the string (remembered as pattern 2).

In the replacement string, you can refer to these matched patterns to use them as part of the replacement. You can also refer to the whole matched portion as &.

So what that sed command is doing is creating a mv command based on the original file (for the source) and character 1 and 3 onwards, effectively removing character 2 (for the destination). It will give you a series of lines along the following format:

mv F00001-0708-RG-biasliuyda F0001-0708-RG-biasliuyda
mv abcdef acdef

and so on.

The infamous java.sql.SQLException: No suitable driver found

For me the same error occurred while connecting to postgres while creating a dataframe from table .It was caused due to,the missing dependency. jdbc dependency was not set .I was using maven for the build ,so added the required dependency to the pom file from maven dependency

jdbc dependency

How do I return a char array from a function?

When you create local variables inside a function that are created on the stack, they most likely get overwritten in memory when exiting the function.

So code like this in most C++ implementations will not work:

char[] populateChar()
{
    char* ch = "wonet return me";
    return ch;
}

A fix is to create the variable that want to be populated outside the function or where you want to use it, and then pass it as a parameter and manipulate the function, example:

void populateChar(char* ch){
    strcpy(ch, "fill me, Will. This will stay", size); // This will work as long as it won't overflow it.
}

int main(){
    char ch[100]; // Reserve memory on the stack outside the function
    populateChar(ch); // Populate the array
}

A C++11 solution using std::move(ch) to cast lvalues to rvalues:

void populateChar(char* && fillme){
    fillme = new char[20];
    strcpy(fillme, "this worked for me");
}

int main(){
    char* ch;
    populateChar(std::move(ch));
    return 0;
}

Or this option in C++11:

char* populateChar(){
    char* ch = "test char";
    // Will change from lvalue to r value
    return std::move(ch);
}

int main(){
    char* ch = populateChar();
    return 0;
}

Show current assembly instruction in GDB

From within gdb press Ctrl x 2 and the screen will split into 3 parts.

First part will show you the normal code in high level language.

Second will show you the assembly equivalent and corresponding instruction Pointer.

Third will present you the normal gdb prompt to enter commands.

See the screen shot

CSS: auto height on containing div, 100% height on background div inside containing div

In 2018 a lot of browsers support the Flexbox and Grid which are very powerful CSS display modes that overshine classical methods such as Faux Columns or Tabular Displays (which are treated later in this answer).

In order to implement this with the Grid, it is enough to specify display: grid and grid-template-columns on the container. The grid-template-columns depends on the number of columns you have, in this example I will use 3 columns, hence the property will look: grid-template-columns: auto auto auto, which basically means that each of the columns will have auto width.

Full working example with Grid:

_x000D_
_x000D_
html, body {_x000D_
    padding: 0;_x000D_
    margin: 0;_x000D_
}_x000D_
_x000D_
.grid-container {_x000D_
    display: grid;_x000D_
    grid-template-columns: auto auto auto;_x000D_
    width: 100%;_x000D_
}_x000D_
_x000D_
.grid-item {_x000D_
    padding: 20px;_x000D_
}_x000D_
_x000D_
.a {_x000D_
    background-color: DarkTurquoise;_x000D_
}_x000D_
_x000D_
.b {_x000D_
    background-color: LightSalmon;_x000D_
}_x000D_
_x000D_
.c {_x000D_
    background-color: LightSteelBlue;_x000D_
}
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
    <title>Three Columns with Grid</title>_x000D_
    <link rel="stylesheet" type="text/css" href="style.css">_x000D_
</head>_x000D_
<body>_x000D_
_x000D_
    <div class="grid-container">_x000D_
        <div class="grid-item a">_x000D_
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas id sapien auctor, faucibus felis et, commodo magna. Sed eu molestie nibh, ac tincidunt turpis. Pellentesque accumsan nunc non arcu tincidunt auctor eget ut magna. In vel est egestas, ultricies dui a, gravida diam. Vivamus tempor facilisis lectus nec porta.</p>_x000D_
        </div>_x000D_
        <div class="grid-item b">_x000D_
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas id sapien auctor, faucibus felis et, commodo magna. Sed eu molestie nibh, ac tincidunt turpis. Pellentesque accumsan nunc non arcu tincidunt auctor eget ut magna. In vel est egestas, ultricies dui a, gravida diam. Vivamus tempor facilisis lectus nec porta. Donec commodo elit mattis, bibendum turpis eu, malesuada nunc. Vestibulum sit amet dui tincidunt, mattis nisl et, tincidunt eros. Vivamus eu ultrices sapien. Integer leo arcu, lobortis sed tellus in, euismod ultricies massa. Mauris gravida quis ligula nec dignissim. Proin elementum mattis fringilla. Donec id malesuada orci, eu aliquam ipsum. Vestibulum fermentum elementum egestas. Quisque sit amet tempor mi.</p>_x000D_
        </div>_x000D_
        <div class="grid-item c">_x000D_
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas id sapien auctor, faucibus felis et, commodo magna. Sed eu molestie nibh, ac tincidunt turpis.</p>_x000D_
        </div>_x000D_
    </div>_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

Another way would be to use the Flexbox by specifying display: flex on the container of the columns, and giving the columns a relevant width. In the example that I will be using, which is with 3 columns, you basically need to split 100% in 3, so it's 33.3333% (close enough, who cares about 0.00003333... which isn't visible anyway).

Full working example using Flexbox:

_x000D_
_x000D_
html, body {_x000D_
    padding: 0;_x000D_
    margin: 0;_x000D_
}_x000D_
_x000D_
.flex-container {_x000D_
    display: flex;_x000D_
    width: 100%;_x000D_
}_x000D_
_x000D_
.flex-column {_x000D_
    padding: 20px;_x000D_
    width: 33.3333%;_x000D_
}_x000D_
_x000D_
.a {_x000D_
    background-color: DarkTurquoise;_x000D_
}_x000D_
_x000D_
.b {_x000D_
    background-color: LightSalmon;_x000D_
}_x000D_
_x000D_
.c {_x000D_
    background-color: LightSteelBlue;_x000D_
}
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
    <title>Three Columns with Flexbox</title>_x000D_
    <link rel="stylesheet" type="text/css" href="style.css">_x000D_
</head>_x000D_
<body>_x000D_
_x000D_
    <div class="flex-container">_x000D_
        <div class="flex-column a">_x000D_
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas id sapien auctor, faucibus felis et, commodo magna. Sed eu molestie nibh, ac tincidunt turpis. Pellentesque accumsan nunc non arcu tincidunt auctor eget ut magna. In vel est egestas, ultricies dui a, gravida diam. Vivamus tempor facilisis lectus nec porta.</p>_x000D_
        </div>_x000D_
        <div class="flex-column b">_x000D_
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas id sapien auctor, faucibus felis et, commodo magna. Sed eu molestie nibh, ac tincidunt turpis. Pellentesque accumsan nunc non arcu tincidunt auctor eget ut magna. In vel est egestas, ultricies dui a, gravida diam. Vivamus tempor facilisis lectus nec porta. Donec commodo elit mattis, bibendum turpis eu, malesuada nunc. Vestibulum sit amet dui tincidunt, mattis nisl et, tincidunt eros. Vivamus eu ultrices sapien. Integer leo arcu, lobortis sed tellus in, euismod ultricies massa. Mauris gravida quis ligula nec dignissim. Proin elementum mattis fringilla. Donec id malesuada orci, eu aliquam ipsum. Vestibulum fermentum elementum egestas. Quisque sit amet tempor mi.</p>_x000D_
        </div>_x000D_
        <div class="flex-column c">_x000D_
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas id sapien auctor, faucibus felis et, commodo magna. Sed eu molestie nibh, ac tincidunt turpis.</p>_x000D_
        </div>_x000D_
    </div>_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

The Flexbox and Grid are supported by all major browsers since 2017/2018, fact also confirmed by caniuse.com: Can I use grid, Can I use flex.

There are also a number of classical solutions, used before the age of Flexbox and Grid, like OneTrueLayout Technique, Faux Columns Technique, CSS Tabular Display Technique and there is also a Layering Technique.

I do not recommend using these methods for they have a hackish nature and are not so elegant in my opinion, but it is good to know them for academic reasons.

A solution for equally height-ed columns is the CSS Tabular Display Technique that means to use the display:table feature. It works for Firefox 2+, Safari 3+, Opera 9+ and IE8.

The code for the CSS Tabular Display:

_x000D_
_x000D_
#container {_x000D_
  display: table;_x000D_
  background-color: #CCC;_x000D_
  margin: 0 auto;_x000D_
}_x000D_
_x000D_
.row {_x000D_
  display: table-row;_x000D_
}_x000D_
_x000D_
.col {_x000D_
  display: table-cell;_x000D_
}_x000D_
_x000D_
#col1 {_x000D_
  background-color: #0CC;_x000D_
  width: 200px;_x000D_
}_x000D_
_x000D_
#col2 {_x000D_
  background-color: #9F9;_x000D_
  width: 300px;_x000D_
}_x000D_
_x000D_
#col3 {_x000D_
  background-color: #699;_x000D_
  width: 200px;_x000D_
}
_x000D_
<div id="container">_x000D_
  <div id="rowWraper" class="row">_x000D_
    <div id="col1" class="col">_x000D_
      Column 1<br />Lorem ipsum<br />ipsum lorem_x000D_
    </div>_x000D_
    <div id="col2" class="col">_x000D_
      Column 2<br />Eco cologna duo est!_x000D_
    </div>_x000D_
    <div id="col3" class="col">_x000D_
      Column 3_x000D_
    </div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Even if there is a problem with the auto-expanding of the width of the table-cell it can be resolved easy by inserting another div withing the table-cell and giving it a fixed width. Anyway, the over-expanding of the width happens in the case of using extremely long words (which I doubt anyone would use a, let's say, 600px long word) or some div's who's width is greater than the table-cell's width.

The Faux Column Technique is the most popular classical solution to this problem, but it has some drawbacks such as, you have to resize the background tiled image if you want to resize the columns and it is also not an elegant solution.

The OneTrueLayout Technique consists of creating a padding-bottom of an extreme big height and cut it out by bringing the real border position to the "normal logical position" by applying a negative margin-bottom of the same huge value and hiding the extent created by the padding with overflow: hidden applied to the content wraper. A simplified example would be:

Working example:

_x000D_
_x000D_
.wraper {_x000D_
    overflow: hidden; /* This is important */_x000D_
}_x000D_
_x000D_
.floatLeft {_x000D_
    float: left;_x000D_
}_x000D_
_x000D_
.block {_x000D_
    padding-left: 20px;_x000D_
    padding-right: 20px;_x000D_
    padding-bottom: 30000px; /* This is important */_x000D_
    margin-bottom: -30000px; /* This is important */_x000D_
    width: 33.3333%;_x000D_
    box-sizing: border-box; /* This is so that the padding right and left does not affect the width */_x000D_
}_x000D_
_x000D_
.a {_x000D_
    background-color: DarkTurquoise;_x000D_
}_x000D_
_x000D_
.b {_x000D_
    background-color: LightSalmon;_x000D_
}_x000D_
_x000D_
.c {_x000D_
    background-color: LightSteelBlue;_x000D_
}
_x000D_
<html>_x000D_
<head>_x000D_
  <title>OneTrueLayout</title>_x000D_
</head>_x000D_
<body>_x000D_
    <div class="wraper">_x000D_
        <div class="block floatLeft a">_x000D_
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras malesuada ipsum pretium tellus condimentum aliquam. Donec eget tempor mi, a consequat enim. Mauris a massa id nisl sagittis iaculis.</p>_x000D_
        </div>_x000D_
        <div class="block floatLeft b">_x000D_
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras malesuada ipsum pretium tellus condimentum aliquam. Donec eget tempor mi, a consequat enim. Mauris a massa id nisl sagittis iaculis. Duis mattis diam vitae tellus ornare, nec vehicula elit luctus. In auctor urna ac ante bibendum, a gravida nunc hendrerit. Praesent sed pellentesque lorem. Nam neque ante, egestas ut felis vel, faucibus tincidunt risus. Maecenas egestas diam massa, id rutrum metus lobortis non. Sed quis tellus sed nulla efficitur pharetra. Fusce semper sapien neque. Donec egestas dolor magna, ut efficitur purus porttitor at. Mauris cursus, leo ac porta consectetur, eros quam aliquet erat, condimentum luctus sapien tellus vel ante. Vivamus vestibulum id lacus vel tristique.</p>_x000D_
        </div>_x000D_
        <div class="block floatLeft c">_x000D_
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras malesuada ipsum pretium tellus condimentum aliquam. Donec eget tempor mi, a consequat enim. Mauris a massa id nisl sagittis iaculis. Duis mattis diam vitae tellus ornare, nec vehicula elit luctus. In auctor urna ac ante bibendum, a gravida nunc hendrerit.</p>_x000D_
        </div>_x000D_
    </div>_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

The Layering Technique must be a very neat solution that involves absolute positioning of div's withing a main relative positioned wrapper div. It basically consists of a number of child divs and the main div. The main div has imperatively position: relative to it's css attribute collection. The children of this div are all imperatively position:absolute. The children must have top and bottom set to 0 and left-right dimensions set to accommodate the columns with each another. For example if we have two columns, one of width 100px and the other one of 200px, considering that we want the 100px in the left side and the 200px in the right side, the left column must have {left: 0; right: 200px} and the right column {left: 100px; right: 0;}

In my opinion the unimplemented 100% height within an automated height container is a major drawback and the W3C should consider revising this attribute (which since 2018 is solvable with Flexbox and Grid).

Other resources: link1, link2, link3, link4, link5 (important)

Dealing with float precision in Javascript

Check out this link.. It helped me a lot.

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

The toPrecision(no_of_digits_required) function returns a string so don't forget to use the parseFloat() function to convert to decimal point of required precision.

if (boolean condition) in Java

In your example, the IF statement will run when it is state = true meaning the else part will run when state = false.

if(turnedOn == true) is the same as if(turnedOn)

if(turnedOn == false) is the same as if(!turnedOn)

If you have:

boolean turnedOn = false;

Or

boolean turnedOn;

Then

if(turnedOn)
{

}
else
{
    // This would run!
}

jQuery slide left and show

This feature is included as part of jquery ui http://docs.jquery.com/UI/Effects/Slide if you want to extend it with your own names you can use this.

jQuery.fn.extend({
  slideRightShow: function() {
    return this.each(function() {
        $(this).show('slide', {direction: 'right'}, 1000);
    });
  },
  slideLeftHide: function() {
    return this.each(function() {
      $(this).hide('slide', {direction: 'left'}, 1000);
    });
  },
  slideRightHide: function() {
    return this.each(function() {
      $(this).hide('slide', {direction: 'right'}, 1000);
    });
  },
  slideLeftShow: function() {
    return this.each(function() {
      $(this).show('slide', {direction: 'left'}, 1000);
    });
  }
});

you will need the following references

<script src="http://code.jquery.com/jquery-latest.js"></script>
<script src="http://jquery-ui.googlecode.com/svn/tags/latest/ui/jquery.effects.core.js"></script>
<script src="http://jquery-ui.googlecode.com/svn/tags/latest/ui/jquery.effects.slide.js"></script>

Access Tomcat Manager App from different host

For Tomcat v8.5.4 and above, the file <tomcat>/webapps/manager/META-INF/context.xml has been adjusted:

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

Change this file to comment the Valve:

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

After that, refresh your browser (not need to restart Tomcat), you can see the manager page.

MySQL OPTIMIZE all tables?

The MySQL Administrator (part of the MySQL GUI Tools) can do that for you on a database level.

Just select your schema and press the Maintenance button in the bottom right corner.

Since the GUI Tools have reached End-of-life status they are hard to find on the mysql page. Found them via Google: http://dev.mysql.com/downloads/gui-tools/5.0.html

I don't know if the new MySQL Workbench can do that, too.

And you can use the mysqlcheck command line tool which should be able to do that, too.

MySQL error - #1932 - Table 'phpmyadmin.pma user config' doesn't exist in engine

Had the same problem in Ubuntu 14 using XAMPP. Here's what I did which worked..

  1. Stop mysql if its running in xampp
  2. vi /opt/lamp/phpmyadmin/config.inc.php (use sudo if you are not the su)
  3. replace

    $cfg['Servers'][1]['relation'] = 'pma__relation';
    $cfg['Servers'][1]['userconfig'] = 'pma__userconfig';
    $cfg['Servers'][1]['table_info'] = 'pma__table_info';
    ...
    

    to

    $cfg['Servers'][1]['pma__relation'] = 'pma__relation';
    $cfg['Servers'][1]['pma__userconfig'] = 'pma__userconfig';
    $cfg['Servers'][1]['pma__table_info'] = 'pma__table_info';
    ...
    

    basically add pma__ prefix to the left side similar to the right.

  4. Run mysql and access localhost/phpmyadmin and click on a db to check if it works.

Hope this helps.

How to alert using jQuery

Don't do this, but this is how you would do it:

$(".overdue").each(function() { 
    alert("Your book is overdue"); 
});

The reason I say "don't do it" is because nothing is more annoying to users, in my opinion, than repeated pop-ups that cannot be stopped. Instead, just use the length property and let them know that "You have X books overdue".

How to find locked rows in Oracle

The below PL/SQL block finds all locked rows in a table. The other answers only find the blocking session, finding the actual locked rows requires reading and testing each row.

(However, you probably do not need to run this code. If you're having a locking problem, it's usually easier to find the culprit using GV$SESSION.BLOCKING_SESSION and other related data dictionary views. Please try another approach before you run this abysmally slow code.)

First, let's create a sample table and some data. Run this in session #1.

--Sample schema.
create table test_locking(a number);
insert into test_locking values(1);
insert into test_locking values(2);
commit;
update test_locking set a = a+1 where a = 1;

In session #2, create a table to hold the locked ROWIDs.

--Create table to hold locked ROWIDs.
create table locked_rowids(the_rowid rowid);
--Remove old rows if table is already created:
--delete from locked_rowids;
--commit;

In session #2, run this PL/SQL block to read the entire table, probe each row, and store the locked ROWIDs. Be warned, this may be ridiculously slow. In your real version of this query, change both references to TEST_LOCKING to your own table.

--Save all locked ROWIDs from a table.
--WARNING: This PL/SQL block will be slow and will temporarily lock rows.
--You probably don't need this information - it's usually good enough to know
--what other sessions are locking a statement, which you can find in
--GV$SESSION.BLOCKING_SESSION.
declare
    v_resource_busy exception;
    pragma exception_init(v_resource_busy, -00054);
    v_throwaway number;
    type rowid_nt is table of rowid;
    v_rowids rowid_nt := rowid_nt();
begin
    --Loop through all the rows in the table.
    for all_rows in
    (
        select rowid
        from test_locking
    ) loop
        --Try to look each row.
        begin
            select 1
            into v_throwaway
            from test_locking
            where rowid = all_rows.rowid
            for update nowait;
        --If it doesn't lock, then record the ROWID.
        exception when v_resource_busy then
            v_rowids.extend;
            v_rowids(v_rowids.count) := all_rows.rowid;
        end;

        rollback;
    end loop;

    --Display count:
    dbms_output.put_line('Rows locked: '||v_rowids.count);

    --Save all the ROWIDs.
    --(Row-by-row because ROWID type is weird and doesn't work in types.)
    for i in 1 .. v_rowids.count loop
        insert into locked_rowids values(v_rowids(i));
    end loop;
    commit;
end;
/

Finally, we can view the locked rows by joining to the LOCKED_ROWIDS table.

--Display locked rows.
select *
from test_locking
where rowid in (select the_rowid from locked_rowids);


A
-
1

Can someone explain mappedBy in JPA and Hibernate?

mappedby="object of entity of same class created in another class”

Note:-Mapped by can be used only in one class because one table must contain foreign key constraint. if mapped by can be applied on both side then it remove foreign key from both table and without foreign key there is no relation b/w two tables.

Note:- it can be use for following annotations:- 1.@OneTone 2.@OneToMany 3.@ManyToMany

Note---It cannot be use for following annotation :- 1.@ManyToOne

In one to one :- Perform at any side of mapping but perform at only one side . It will remove the extra column of foreign key constraint on the table on which class it is applied.

For eg . If we apply mapped by in Employee class on employee object then foreign key from Employee table will be removed.

Go to Matching Brace in Visual Studio?

On a Hungarian keyboard it is Ctrl + ú.