Programs & Examples On #Graphic design

the creative process in which an artist produces imagery to convey a message.

How do I connect to my existing Git repository using Visual Studio Code?

Another option is to use the built-in Command Palette, which will walk you right through cloning a Git repository to a new directory.

From Using Version Control in VS Code:

You can clone a Git repository with the Git: Clone command in the Command Palette (Windows/Linux: Ctrl + Shift + P, Mac: Command + Shift + P). You will be asked for the URL of the remote repository and the parent directory under which to put the local repository.

At the bottom of Visual Studio Code you'll get status updates to the cloning. Once that's complete an information message will display near the top, allowing you to open the folder that was created.

Note that Visual Studio Code uses your machine's Git installation, and requires 2.0.0 or higher.

How would you implement an LRU cache in Java?

Here is my short implementation, please criticize or improve it!

package util.collection;

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentLinkedQueue;

/**
 * Limited size concurrent cache map implementation.<br/>
 * LRU: Least Recently Used.<br/>
 * If you add a new key-value pair to this cache after the maximum size has been exceeded,
 * the oldest key-value pair will be removed before adding.
 */

public class ConcurrentLRUCache<Key, Value> {

private final int maxSize;
private int currentSize = 0;

private ConcurrentHashMap<Key, Value> map;
private ConcurrentLinkedQueue<Key> queue;

public ConcurrentLRUCache(final int maxSize) {
    this.maxSize = maxSize;
    map = new ConcurrentHashMap<Key, Value>(maxSize);
    queue = new ConcurrentLinkedQueue<Key>();
}

private synchronized void freeSpace() {
    Key key = queue.poll();
    if (null != key) {
        map.remove(key);
        currentSize = map.size();
    }
}

public void put(Key key, Value val) {
    if (map.containsKey(key)) {// just heat up that item
        put(key, val);
        return;
    }
    while (currentSize >= maxSize) {
        freeSpace();
    }
    synchronized(this) {
        queue.add(key);
        map.put(key, val);
        currentSize++;
    }
}

public Value get(Key key) {
    return map.get(key);
}
}

Why is datetime.strptime not working in this simple example?

You can also do the following,to import datetime

from datetime import datetime as dt

dt.strptime(date, '%Y-%m-%d')

How to create a dotted <hr/> tag?

You can do:

<hr style="border: 1px dashed black;" />

Demo: http://jsfiddle.net/JMfC9/

Using Mockito's generic "any()" method

Since Java 8 you can use the argument-less any method and the type argument will get inferred by the compiler:

verify(bar).doStuff(any());

Explanation

The new thing in Java 8 is that the target type of an expression will be used to infer type parameters of its sub-expressions. Before Java 8 only arguments to methods where used for type parameter inference (most of the time).

In this case the parameter type of doStuff will be the target type for any(), and the return value type of any() will get chosen to match that argument type.

This mechanism was added in Java 8 mainly to be able to compile lambda expressions, but it improves type inferences generally.


Primitive types

This doesn't work with primitive types, unfortunately:

public interface IBar {
    void doPrimitiveStuff(int i);
}

verify(bar).doPrimitiveStuff(any()); // Compiles but throws NullPointerException
verify(bar).doPrimitiveStuff(anyInt()); // This is what you have to do instead

The problem is that the compiler will infer Integer as the return value type of any(). Mockito will not be aware of this (due to type erasure) and return the default value for reference types, which is null. The runtime will try to unbox the return value by calling the intValue method on it before passing it to doStuff, and the exception gets thrown.

href="file://" doesn't work

The reason your URL is being rewritten to file///K:/AmberCRO%20SOP/2011-07-05/SOP-SOP-3.0.pdf is because you specified http://file://

The http:// at the beginning is the protocol being used, and your browser is stripping out the second colon (:) because it is invalid.

Note

If you link to something like

<a href="file:///K:/yourfile.pdf">yourfile.pdf</a>

The above represents a link to a file called k:/yourfile.pdf on the k: drive on the machine on which you are viewing the URL.

You can do this, for example the below creates a link to C:\temp\test.pdf

<a href="file:///C:/Temp/test.pdf">test.pdf</a>

By specifying file:// you are indicating that this is a local resource. This resource is NOT on the internet.

Most people do not have a K:/ drive.

But, if this is what you are trying to achieve, that's fine, but this is not how a "typical" link on a web page works, and you shouldn't being doing this unless everyone who is going to access your link has access to the (same?) K:/drive (this might be the case with a shared network drive).

You could try

<a href="file:///K:/AmberCRO-SOP/2011-07-05/SOP-SOP-3.0.pdf">test.pdf</a>
<a href="AmberCRO-SOP/2011-07-05/SOP-SOP-3.0.pdf">test.pdf</a>
<a href="2011-07-05/SOP-SOP-3.0.pdf">test.pdf</a>

Note that http://file:///K:/AmberCRO%20SOP/2011-07-05/SOP-SOP-3.0.pdf is a malformed

Insert data into a view (SQL Server)

You just need to specify which columns you're inserting directly into:

INSERT INTO [dbo].[rLicenses] ([Name]) VALUES ('test')

Views can be picky like that.

Using current time in UTC as default value in PostgreSQL

What about

now()::timestamp

If your other timestamp are without time zone then this cast will yield the matching type "timestamp without time zone" for the current time.

I would like to read what others think about that option, though. I still don't trust in my understanding of this "with/without" time zone stuff.

EDIT: Adding Michael Ekoka's comment here because it clarifies an important point:

Caveat. The question is about generating default timestamp in UTC for a timestamp column that happens to not store the time zone (perhaps because there's no need to store the time zone if you know that all your timestamps share the same). What your solution does is to generate a local timestamp (which for most people will not necessarily be set to UTC) and store it as a naive timestamp (one that does not specify its time zone).

Remove large .pack file created by git

The issue is that, even though you removed the files, they are still present in previous revisions. That's the whole point of git, is that even if you delete something, you can still get it back by accessing the history.

What you are looking to do is called rewriting history, and it involved the git filter-branch command.

GitHub has a good explanation of the issue on their site. https://help.github.com/articles/remove-sensitive-data

To answer your question more directly, what you basically need to run is this command with unwanted_filename_or_folder replaced accordingly:

git filter-branch --index-filter 'git rm -r --cached --ignore-unmatch unwanted_filename_or_folder' --prune-empty

This will remove all references to the files from the active history of the repo.

Next step, to perform a GC cycle to force all references to the file to be expired and purged from the packfile. Nothing needs to be replaced in these commands.

git for-each-ref --format='delete %(refname)' refs/original | git update-ref --stdin
# or, for older git versions (e.g. 1.8.3.1) which don't support --stdin
# git update-ref $(git for-each-ref --format='delete %(refname)' refs/original)
git reflog expire --expire=now --all
git gc --aggressive --prune=now

MongoDB: update every document on one field

I have been using MongoDB .NET driver for a little over a month now. If I were to do it using .NET driver, I would use Update method on the collection object. First, I will construct a query that will get me all the documents I am interested in and do an Update on the fields I want to change. Update in Mongo only affects the first document and to update all documents resulting from the query one needs to use 'Multi' update flag. Sample code follows...

var collection = db.GetCollection("Foo");
var query = Query.GTE("No", 1); // need to construct in such a way that it will give all 20K //docs.
var update = Update.Set("timestamp", datetime.UtcNow);
collection.Update(query, update, UpdateFlags.Multi);

Sort an array of objects in React and render them

You will need to sort your object before mapping over them. And it can be done easily with a sort() function with a custom comparator definition like

var obj = [...this.state.data];
obj.sort((a,b) => a.timeM - b.timeM);
obj.map((item, i) => (<div key={i}> {item.matchID}  
                      {item.timeM} {item.description}</div>))

How can I INSERT data into two tables simultaneously in SQL Server?

BEGIN TRANSACTION;

DECLARE @tblMapping table(sourceid int, destid int)

INSERT INTO [table1] ([data]) 
OUTPUT source.id, new.id
Select [data] from [external_table] source;

INSERT INTO [table2] ([table1_id], [data])
Select map.destid, source.[more data] 
from [external_table] source
    inner join @tblMapping map on source.id=map.sourceid;

COMMIT TRANSACTION;

Inconsistent Accessibility: Parameter type is less accessible than method

Make the class public.

class NewClass
{

}

is the same as:

internal class NewClass
{

}

so the class has to be public

Download a single folder or directory from a GitHub repo

Update Sep. 2016: there are a few tools created by the community that can do this for you:


Git doesn't support this, but Github does via SVN. If you checkout your code with subversion, Github will essentially convert the repo from git to subversion on the backend, then serve up the requested directory.

Here's how you can use this feature to download a specific folder. I'll use the popular javascript library lodash as an example.

  1. Navigate to the folder you want to download. Let's download /test from master branch. github repo URL example

  2. Modify the URL for subversion. Replace tree/master with trunk.

    https://github.com/lodash/lodash/tree/master/test ?

    https://github.com/lodash/lodash/trunk/test

  3. Download the folder. Go to the command line and grab the folder with SVN.

svn checkout https://github.com/lodash/lodash/trunk/test

You might not see any activity immediately because Github takes up to 30 seconds to convert larger repositories, so be patient.

Full URL format explanation:

  • If you're interested in master branch, use trunk instead. So the full path is trunk/foldername
  • If you're interested in foo branch, use branches/foo instead. The full path looks like branches/foo/foldername
  • Protip: You can use svn ls to see available tags and branches before downloading if you wish

That's all! Github supports more subversion features as well, including support for committing and pushing changes.

How to submit a form using PhantomJS

I figured it out. Basically it's an async issue. You can't just submit and expect to render the subsequent page immediately. You have to wait until the onLoad event for the next page is triggered. My code is below:

var page = new WebPage(), testindex = 0, loadInProgress = false;

page.onConsoleMessage = function(msg) {
  console.log(msg);
};

page.onLoadStarted = function() {
  loadInProgress = true;
  console.log("load started");
};

page.onLoadFinished = function() {
  loadInProgress = false;
  console.log("load finished");
};

var steps = [
  function() {
    //Load Login Page
    page.open("https://website.com/theformpage/");
  },
  function() {
    //Enter Credentials
    page.evaluate(function() {

      var arr = document.getElementsByClassName("login-form");
      var i;

      for (i=0; i < arr.length; i++) { 
        if (arr[i].getAttribute('method') == "POST") {

          arr[i].elements["email"].value="mylogin";
          arr[i].elements["password"].value="mypassword";
          return;
        }
      }
    });
  }, 
  function() {
    //Login
    page.evaluate(function() {
      var arr = document.getElementsByClassName("login-form");
      var i;

      for (i=0; i < arr.length; i++) {
        if (arr[i].getAttribute('method') == "POST") {
          arr[i].submit();
          return;
        }
      }

    });
  }, 
  function() {
    // Output content of page to stdout after form has been submitted
    page.evaluate(function() {
      console.log(document.querySelectorAll('html')[0].outerHTML);
    });
  }
];


interval = setInterval(function() {
  if (!loadInProgress && typeof steps[testindex] == "function") {
    console.log("step " + (testindex + 1));
    steps[testindex]();
    testindex++;
  }
  if (typeof steps[testindex] != "function") {
    console.log("test complete!");
    phantom.exit();
  }
}, 50);

Failed to execute removeChild on Node

As others have mentioned, myCoolDiv is a child of markerDiv not playerContainer. If you want to remove myCoolDiv but keep markerDiv for some reason you can do the following

myCoolDiv.parentNode.removeChild(myCoolDiv);

JSFiddle

How to get GMT date in yyyy-mm-dd hh:mm:ss in PHP

You are repeating the y,m,d.

Instead of

gmdate('yyyy-mm-dd hh:mm:ss \G\M\T', time());  

You should use it like

gmdate('Y-m-d h:m:s \G\M\T', time());

Convert list of ints to one number?

This method works in 2.x as long as each element in the list is only a single digit. But you shouldn't actually use this. It's horrible.

>>> magic = lambda l:int(`l`[1::3])
>>> magic([3,1,3,3,7])
31337

import module from string variable

I developed these 3 useful functions:

def loadModule(moduleName):
    module = None
    try:
        import sys
        del sys.modules[moduleName]
    except BaseException as err:
        pass
    try:
        import importlib
        module = importlib.import_module(moduleName)
    except BaseException as err:
        serr = str(err)
        print("Error to load the module '" + moduleName + "': " + serr)
    return module

def reloadModule(moduleName):
    module = loadModule(moduleName)
    moduleName, modulePath = str(module).replace("' from '", "||").replace("<module '", '').replace("'>", '').split("||")
    if (modulePath.endswith(".pyc")):
        import os
        os.remove(modulePath)
        module = loadModule(moduleName)
    return module

def getInstance(moduleName, param1, param2, param3):
    module = reloadModule(moduleName)
    instance = eval("module." + moduleName + "(param1, param2, param3)")
    return instance

And everytime I want to reload a new instance I just have to call getInstance() like this:

myInstance = getInstance("MyModule", myParam1, myParam2, myParam3)

Finally I can call all the functions inside the new Instance:

myInstance.aFunction()

The only specificity here is to customize the params list (param1, param2, param3) of your instance.

Create autoincrement key in Java DB using NetBeans IDE

If you look at this url: http://java.sun.com/developer/technicalArticles/J2SE/Desktop/javadb/

this part of the schema may be what you are looking for.

 ID          INTEGER NOT NULL 
                PRIMARY KEY GENERATED ALWAYS AS IDENTITY 
                (START WITH 1, INCREMENT BY 1),

How to insert an image in python

Install PIL(Python Image Library) :

then:

from PIL import Image
myImage = Image.open("your_image_here");
myImage.show();

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

If you have BSD (OSX) date you can do it like this:

date -j -v-1d
Wed Dec 14 15:34:14 CET 2011

Or if you want to do date calculations on an arbitrary date:

date -j -v-1d -f "%Y-%m-%d" "2011-09-01" "+%Y-%m-%d"
2011-08-31

How to set combobox default value?

Suppose you bound your combobox to a List<Person>

List<Person> pp = new List<Person>();
pp.Add(new Person() {id = 1, name="Steve"});
pp.Add(new Person() {id = 2, name="Mark"});
pp.Add(new Person() {id = 3, name="Charles"});

cbo1.DisplayMember = "name";
cbo1.ValueMember = "id";
cbo1.DataSource = pp;

At this point you cannot set the Text property as you like, but instead you need to add an item to your list before setting the datasource

pp.Insert(0, new Person() {id=-1, name="--SELECT--"});
cbo1.DisplayMember = "name";
cbo1.ValueMember = "id";
cbo1.DataSource = pp;
cbo1.SelectedIndex = 0;

Of course this means that you need to add a checking code when you try to use the info from the combobox

if(cbo1.SelectedValue != null && Convert.ToInt32(cbo1.SelectedValue) == -1)
    MessageBox.Show("Please select a person name");
else
    ...... 

The code is the same if you use a DataTable instead of a list. You need to add a fake row at the first position of the Rows collection of the datatable and set the initial index of the combobox to make things clear. The only thing you need to look at are the name of the datatable columns and which columns should contain a non null value before adding the row to the collection

In a table with three columns like ID, FirstName, LastName with ID,FirstName and LastName required you need to

DataRow row = datatable.NewRow();
row["ID"] = -1;
row["FirstName"] = "--Select--";    
row["LastName"] = "FakeAddress";
dataTable.Rows.InsertAt(row, 0);

Margin-Top not working for span element?

span is an inline element that doesn't support vertical margins. Put the margin on the outer div instead.

JPA: unidirectional many-to-one and cascading delete

You don't need to use bi-directional association instead of your code, you have just to add CascaType.Remove as a property to ManyToOne annotation, then use @OnDelete(action = OnDeleteAction.CASCADE), it's works fine for me.

Android view pager with page indicator

you have to do following:

1-Download the full project from here https://github.com/JakeWharton/ViewPagerIndicator ViewPager Indicator 2- Import into the Eclipse.

After importing if you want to make following type of screen then follow below steps -

Screen Shot

change in

Sample circles Default

  package com.viewpagerindicator.sample;
  import android.os.Bundle;  
  import android.support.v4.view.ViewPager;
  import com.viewpagerindicator.CirclePageIndicator;

  public class SampleCirclesDefault extends BaseSampleActivity {
   @Override
   protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.simple_circles);

    mAdapter = new TestFragmentAdapter(getSupportFragmentManager());

    mPager = (ViewPager)findViewById(R.id.pager);
  //  mPager.setAdapter(mAdapter);

    ImageAdapter adapter = new ImageAdapter(SampleCirclesDefault.this);
    mPager.setAdapter(adapter);


    mIndicator = (CirclePageIndicator)findViewById(R.id.indicator);
    mIndicator.setViewPager(mPager);
  }
}

ImageAdapter

 package com.viewpagerindicator.sample;

 import android.content.Context;
 import android.support.v4.view.PagerAdapter;
 import android.support.v4.view.ViewPager;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.ImageView;
 import android.widget.TextView;

 public class ImageAdapter extends PagerAdapter {
 private Context mContext;

 private Integer[] mImageIds = { R.drawable.about1, R.drawable.about2,
        R.drawable.about3, R.drawable.about4, R.drawable.about5,
        R.drawable.about6, R.drawable.about7

 };

 public ImageAdapter(Context context) {
    mContext = context;
 }

 public int getCount() {
    return mImageIds.length;
 }

 public Object getItem(int position) {
    return position;
 }

 public long getItemId(int position) {
    return position;
 }

 @Override
 public Object instantiateItem(ViewGroup container, final int position) {

    LayoutInflater inflater = (LayoutInflater) container.getContext()
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    View convertView = inflater.inflate(R.layout.gallery_view, null);

    ImageView view_image = (ImageView) convertView
            .findViewById(R.id.view_image);
    TextView description = (TextView) convertView
            .findViewById(R.id.description);

    view_image.setImageResource(mImageIds[position]);
    view_image.setScaleType(ImageView.ScaleType.FIT_XY);

    description.setText("The natural habitat of the Niligiri tahr,Rajamala          Rajamala is 2695 Mts above sea level"
        + "The natural habitat of the Niligiri tahr,Rajamala Rajamala is 2695 Mts above sea level"
                    + "The natural habitat of the Niligiri tahr,Rajamala Rajamala is 2695 Mts above sea level");

    ((ViewPager) container).addView(convertView, 0);

    return convertView;
 }

 @Override
 public boolean isViewFromObject(View view, Object object) {
    return view == ((View) object);
 }

 @Override
 public void destroyItem(ViewGroup container, int position, Object object) {
    ((ViewPager) container).removeView((ViewGroup) object);
 }
}

gallery_view.xml

 <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@drawable/about_bg"
android:orientation="vertical" >

<LinearLayout
    android:id="@+id/about_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:weightSum="1" >

    <LinearLayout
        android:id="@+id/about_layout1"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight=".4"
        android:orientation="vertical" >

        <ImageView
            android:id="@+id/view_image"
            android:layout_width="match_parent"
            android:layout_height="match_parent" 
            android:background="@drawable/about1">
     </ImageView>
    </LinearLayout>

    <LinearLayout
        android:id="@+id/about_layout2"
        android:layout_width="fill_parent"
        android:layout_height="0dp"
        android:layout_weight=".6"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/textView1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="SIGNATURE LANDMARK OF MALAYSIA-SINGAPORE CAUSEWAY"
            android:textColor="#000000"
            android:gravity="center"
            android:padding="18dp"
            android:textStyle="bold"
            android:textAppearance="?android:attr/textAppearance" />


        <ScrollView
            android:layout_width="fill_parent"
            android:layout_height="match_parent"
            android:fillViewport="false"
            android:orientation="vertical"
            android:scrollbars="none"
            android:layout_marginBottom="10dp"
            android:padding="10dp" >

            <TextView
                android:id="@+id/description"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:textColor="#000000"
                android:text="TextView" />

            </ScrollView>
    </LinearLayout>
 </LinearLayout>

CSS3 Box Shadow on Top, Left, and Right Only

Adding a separate answer because it is radically different.

You could use rgba and set the alpha channel low (to get transparency) to make your drop shadow less noticeable.

Try something like this (play with the .5)

-webkit-box-shadow: 0px -4px 7px rbga(230, 230, 230, .5);
-moz-box-shadow: 0px -4px 7px rbga(230, 230, 230, .5);
box-shadow: 0px -4px 7px rbga(230, 230, 230, .5);

Hope this helps!

python pandas remove duplicate columns

I ran into this problem where the one liner provided by the first answer worked well. However, I had the extra complication where the second copy of the column had all of the data. The first copy did not.

The solution was to create two data frames by splitting the one data frame by toggling the negation operator. Once I had the two data frames, I ran a join statement using the lsuffix. This way, I could then reference and delete the column without the data.

- E

CSS: 100% width or height while keeping aspect ratio?

Simple solution:

min-height: 100%;
min-width: 100%;
width: auto;
height: auto;
margin: 0;
padding: 0;

By the way, if you want to center it in a parent div container, you can add those css properties:

position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);

It should really work as expected :)

JS Client-Side Exif Orientation: Rotate and Mirror JPEG Images

Wunderbart's post worked for me combined with statler's improvements. Adding a few more comments and syntax cleanup, and also passing back the orientation value and I have the following code feel free to use. Just call readImageFile() function below and you get back the transformed image and the original orientation.

const JpegOrientation = [
    "NOT_JPEG",
    "NORMAL",
    "FLIP-HORIZ",
    "ROT180",
    "FLIP-HORIZ-ROT180",
    "FLIP-HORIZ-ROT270",
    "ROT270",
    "FLIP-HORIZ-ROT90",
    "ROT90"
];


//Provided a image file, determines the orientation of the file based on the EXIF information.
//Calls the "callback" function with an index into the JpegOrientation array. 
//If the image is not a JPEG, returns 0. If  the orientation value cannot be read (corrupted file?) return -1.
function getOrientation(file, callback) {
    
    const reader = new FileReader();
    reader.onload = (e) => {

        const view = new DataView(e.target.result);
        
        if (view.getUint16(0, false) !== 0xFFD8) {
            return callback(0);  //NOT A JPEG FILE
        }
        
        const length = view.byteLength;
        let offset = 2;
        while (offset < length) {
            
            if (view.getUint16(offset+2, false) <= 8)   //unknown?
                return callback(-1);
            
            const marker = view.getUint16(offset, false);
            offset += 2;
            if (marker === 0xFFE1) {
                
                if (view.getUint32(offset += 2, false) !== 0x45786966) 
                    return callback(-1); //unknown?
                

                const little = view.getUint16(offset += 6, false) === 0x4949;
                offset += view.getUint32(offset + 4, little);
                const tags = view.getUint16(offset, little);
                offset += 2;
                for (var i = 0; i < tags; i++) {
                    if (view.getUint16(offset + (i * 12), little) === 0x0112) {
                        return callback(view.getUint16(offset + (i * 12) + 8, little));   //found orientation code
                    }
                }
            }
            else if ((marker & 0xFF00) !== 0xFF00) {
                break;
            }
            else { 
                offset += view.getUint16(offset, false);
            }
        }
        
        return callback(-1); //unknown?
    };
    reader.readAsArrayBuffer(file);
}

//Takes a jpeg image file as base64 and transforms it back to original, providing the
//transformed image in callback.  If the image is not a jpeg or is already in normal orientation,
//just calls the callback directly with the source.
//Set type to the desired output type if transformed, default is image/jpeg for speed.
function resetOrientation(srcBase64, srcOrientation, callback, type = "image/jpeg") {
    
    if (srcOrientation <= 1) {  //no transform needed
        callback(srcBase64);
        return;
    }
    
    const img = new Image();    

    img.onload = () => {
        const width = img.width;
        const height = img.height;
        const canvas = document.createElement('canvas');
        const ctx = canvas.getContext("2d");

        // set proper canvas dimensions before transform & export
        if (4 < srcOrientation && srcOrientation < 9) {
            canvas.width = height;
            canvas.height = width;
        } else {
            canvas.width = width;
            canvas.height = height;
        }

        // transform context before drawing image
        switch (srcOrientation) {
              
              //case 1: normal, no transform needed
              
              case 2:  
                  ctx.transform(-1, 0, 0, 1, width, 0); 
                  break;
              case 3:
                  ctx.transform(-1, 0, 0, -1, width, height); 
                  break;
              case 4: 
                  ctx.transform(1, 0, 0, -1, 0, height); 
                  break;
              case 5: 
                  ctx.transform(0, 1, 1, 0, 0, 0); 
                  break;
              case 6: 
                  ctx.transform(0, 1, -1, 0, height, 0); 
                  break;
              case 7: 
                  ctx.transform(0, -1, -1, 0, height, width); 
                  break;
              case 8: 
                  ctx.transform(0, -1, 1, 0, 0, width); 
                  break;
              default: 
                  break;
        }

        // draw image
        ctx.drawImage(img, 0, 0);

        //export base64
        callback(canvas.toDataURL(type), srcOrientation);
    };

    img.src = srcBase64;
};


//Read an image file, providing the returned data to callback. If the image is jpeg
//and is transformed according to EXIF info, transform it first.
//The callback function receives the image data and the orientation value (index into JpegOrientation)
export function readImageFile(file, callback) {

    getOrientation(file, (orientation) => {

        console.log("Read file \"" + file.name + "\" with orientation: " + JpegOrientation[orientation]);

        const reader = new FileReader();
        reader.onload = () => {  //when reading complete

            const img = reader.result;
            resetOrientation(img, orientation, callback);
        };
        reader.readAsDataURL(file);  //start read
        
    });
}

Sleep function in ORACLE

Short of granting access to DBMS_LOCK.sleep, this will work but it's a horrible hack:

IN_TIME INT; --num seconds
v_now DATE;

-- 1) Get the date & time 
SELECT SYSDATE 
  INTO v_now
  FROM DUAL;

-- 2) Loop until the original timestamp plus the amount of seconds <= current date
LOOP
  EXIT WHEN v_now + (IN_TIME * (1/86400)) <= SYSDATE;
END LOOP;

Image steganography that could survive jpeg compression

Quite a few applications seem to implement Steganography on JPEG, so it's feasible:

http://www.jjtc.com/Steganography/toolmatrix.htm

Here's an article regarding a relevant algorithm (PM1) to get you started:

http://link.springer.com/article/10.1007%2Fs00500-008-0327-7#page-1

How do I generate a list with a specified increment step?

Executing seq(1, 10, 1) does what 1:10 does. You can change the last parameter of seq, i.e. by, to be the step of whatever size you like.

> #a vector of even numbers
> seq(0, 10, by=2) # Explicitly specifying "by" only to increase readability 
> [1]  0  2  4  6  8 10

How to disable/enable select field using jQuery?

To be able to disable/enable selects first of all your selects need an ID or class. Then you could do something like this:

Disable:

$('#id').attr('disabled', 'disabled');

Enable:

$('#id').removeAttr('disabled');

How to cache data in a MVC application

public sealed class CacheManager
{
    private static volatile CacheManager instance;
    private static object syncRoot = new Object();
    private ObjectCache cache = null;
    private CacheItemPolicy defaultCacheItemPolicy = null;

    private CacheEntryRemovedCallback callback = null;
    private bool allowCache = true;

    private CacheManager()
    {
        cache = MemoryCache.Default;
        callback = new CacheEntryRemovedCallback(this.CachedItemRemovedCallback);

        defaultCacheItemPolicy = new CacheItemPolicy();
        defaultCacheItemPolicy.AbsoluteExpiration = DateTime.Now.AddHours(1.0);
        defaultCacheItemPolicy.RemovedCallback = callback;
        allowCache = StringUtils.Str2Bool(ConfigurationManager.AppSettings["AllowCache"]); ;
    }
    public static CacheManager Instance
    {
        get
        {
            if (instance == null)
            {
                lock (syncRoot)
                {
                    if (instance == null)
                    {
                        instance = new CacheManager();
                    }
                }
            }

            return instance;
        }
    }

    public IEnumerable GetCache(String Key)
    {
        if (Key == null || !allowCache)
        {
            return null;
        }

        try
        {
            String Key_ = Key;
            if (cache.Contains(Key_))
            {
                return (IEnumerable)cache.Get(Key_);
            }
            else
            {
                return null;
            }
        }
        catch (Exception)
        {
            return null;
        }
    }

    public void ClearCache(string key)
    {
        AddCache(key, null);
    }

    public bool AddCache(String Key, IEnumerable data, CacheItemPolicy cacheItemPolicy = null)
    {
        if (!allowCache) return true;
        try
        {
            if (Key == null)
            {
                return false;
            }

            if (cacheItemPolicy == null)
            {
                cacheItemPolicy = defaultCacheItemPolicy;
            }

            String Key_ = Key;

            lock (Key_)
            {
                return cache.Add(Key_, data, cacheItemPolicy);
            }
        }
        catch (Exception)
        {
            return false;
        }
    }

    private void CachedItemRemovedCallback(CacheEntryRemovedArguments arguments)
    {
        String strLog = String.Concat("Reason: ", arguments.RemovedReason.ToString(), " | Key-Name: ", arguments.CacheItem.Key, " | Value-Object: ", arguments.CacheItem.Value.ToString());
        LogManager.Instance.Info(strLog);
    }
}

setting request headers in selenium

With the solutions already discussed above the most reliable one is using Browsermob-Proxy

But while working with the remote grid machine, Browsermob-proxy isn't really helpful.

This is how I fixed the problem in my case. Hopefully, might be helpful for anyone with a similar setup.

  1. Add the ModHeader extension to the chrome browser

How to download the Modheader? Link

ChromeOptions options = new ChromeOptions();
options.addExtensions(new File(C://Downloads//modheader//modheader.crx));

// Set the Desired capabilities 
DesiredCapabilities capabilities = new DesiredCapabilities();
capabilities.setCapability(ChromeOptions.CAPABILITY, options);

// Instantiate the chrome driver with capabilities
WebDriver driver = new RemoteWebDriver(new URL(YOUR_HUB_URL), options);
  1. Go to the browser extensions and capture the Local Storage context ID of the ModHeader

Capture ID from ModHeader

  1. Navigate to the URL of the ModHeader to set the Local Storage Context

.

// set the context on the extension so the localStorage can be accessed
driver.get("chrome-extension://idgpnmonknjnojddfkpgkljpfnnfcklj/_generated_background_page.html");

Where `idgpnmonknjnojddfkpgkljpfnnfcklj` is the value captured from the Step# 2
  1. Now add the headers to the request using Javascript

.

   ((Javascript)driver).executeScript(
         "localStorage.setItem('profiles', JSON.stringify([{  title: 'Selenium', hideComment: true, appendMode: '', 
             headers: [                        
               {enabled: true, name: 'token-1', value: 'value-1', comment: ''},
               {enabled: true, name: 'token-2', value: 'value-2', comment: ''}
             ],                          
             respHeaders: [],
             filters: []
          }]));");

Where token-1, value-1, token-2, value-2 are the request headers and values that are to be added.

  1. Now navigate to the required web-application.

    driver.get("your-desired-website");

How to set bootstrap navbar active class with Angular JS?

Here's another solution for anyone who might be interested. The advantage of this is it has fewer dependencies. Heck, it works without a web server too. So it's completely client-side.

HTML:

<nav class="navbar navbar-inverse" ng-controller="topNavBarCtrl"">
<div class="container-fluid">
    <div class="navbar-header">
        <a class="navbar-brand" href="#"><span class="glyphicon glyphicon-home" aria-hidden="true"></span></a>
    </div>
    <ul class="nav navbar-nav">
        <li ng-click="selectTab()" ng-class="getTabClass()"><a href="#">Home</a></li>
        <li ng-repeat="tab in tabs" ng-click="selectTab(tab)" ng-class="getTabClass(tab)"><a href="#">{{ tab }}</a></li>
    </ul>
</div>

Explanation:

Here we are generating the links dynamically from an angularjs model using the directive ng-repeat. Magic happens with the methods selectTab() and getTabClass() defined in the controller for this navbar presented below.

Controller:

angular.module("app.NavigationControllersModule", [])

// Constant named 'activeTab' holding the value 'active'. We will use this to set the class name of the <li> element that is selected.
.constant("activeTab", "active")

.controller("topNavBarCtrl", function($scope, activeTab){
    // Model used for the ng-repeat directive in the template.
    $scope.tabs = ["Page 1", "Page 2", "Page 3"];

    var selectedTab = null;

    // Sets the selectedTab.
    $scope.selectTab = function(newTab){
       selectedTab = newTab;
    };

    // Sets class of the selectedTab to 'active'.
    $scope.getTabClass = function(tab){
       return selectedTab == tab ? activeTab : "";
    };
});

Explanation:

selectTab() method is called using ng-click directive. So when the link is clicked, the variable selectedTab is set to the name of this link. In the HTML you can see that this method is called without any argument for Home tab so that it will be highlighted when the page loads.

The getTabClass() method is called via ng-class directive in the HTML. This method checks if the tab it is in is the same as the value of the selectedTab variable. If true, it returns "active" else returns "" which is applied as the class name by ng-class directive. Then whatever css you have applied to class active will be applied to the selected tab.

UML class diagram enum

If your UML modeling tool has support for specifying an Enumeration, you should use that. It will likely be easier to do and it will give your model stronger semantics. Visually the result will be very similar to a Class with an <<enumeration>> Stereotype, but in the UML metamodel, an Enumeration is actually a separate (meta)type.

+---------------------+
|   <<enumeration>>   |
|    DayOfTheWeek     |
|_____________________|
| Sunday              |
| Monday              |
| Tuesday             |
| ...                 |
+---------------------+

Once it is defined, you can use it as the type of an Attribute just like you would a Datatype or the name one of your own Classes.

+---------------------+
|        Event        |
|_____________________|
| day : DayOfTheWeek  |
| ...                 |
+---------------------+

If you're using ArgoEclipse or ArgoUML, there's a pulldown menu on the toolbar which selects among Datatype, Enumeration, Signal, etc that will allow you to create your own Enumerations. The compartment that normally contains Attributes can then be populated with EnumerationLiterals for the values of your enumeration.

Here's a picture of a slightly different example in ArgoUML: enter image description here

How to set page content to the middle of screen?

If you want to center the content horizontally and vertically, but don't know in prior how high your page will be, you have to you use JavaScript.

HTML:

<body>
    <div id="content">...</div>
</body>

CSS:

#content {
    max-width: 1000px;
    margin: auto;
    left: 1%;
    right: 1%;
    position: absolute;
}

JavaScript (using jQuery):

$(function() {
    $(window).on('resize', function resize()  {
        $(window).off('resize', resize);
        setTimeout(function () {
            var content = $('#content');
            var top = (window.innerHeight - content.height()) / 2;
            content.css('top', Math.max(0, top) + 'px');
            $(window).on('resize', resize);
        }, 50);
    }).resize();
});

Centered horizontally and vertically

Demo: http://jsfiddle.net/nBzcb/

Convert a timedelta to days, hours and minutes

If you have a datetime.timedelta value td, td.days already gives you the "days" you want. timedelta values keep fraction-of-day as seconds (not directly hours or minutes) so you'll indeed have to perform "nauseatingly simple mathematics", e.g.:

def days_hours_minutes(td):
    return td.days, td.seconds//3600, (td.seconds//60)%60

How to fix 'Unchecked runtime.lastError: The message port closed before a response was received' chrome issue?

If error reason is extension use incognito Ctrl+Shift+N. In incognito mode Chrome does not have extensions.

UPD. If you need some extension in incognito mode e.g. ReduxDevTools or any other, in extension settings turn on "Allow in incognito"

What static analysis tools are available for C#?

Have you seen CAT.NET?

From the blurb -

CAT.NET is a binary code analysis tool that helps identify common variants of certain prevailing vulnerabilities that can give rise to common attack vectors such as Cross-Site Scripting (XSS), SQL Injection and XPath Injection.

I used an early beta and it did seem to turn up a few things worth looking at.

How to extract text from a string using sed?

How about using grep -E?

echo "This is 02G05 a test string 20-Jul-2012" | grep -Eo '[0-9]+G[0-9]+'

open_basedir restriction in effect. File(/) is not within the allowed path(s):

Check \httpdocs\bootstrap\cache\config.php file in plesk to see if there are some unwanted paths.

How to print something when running Puppet client?

You can run the client like this ...

puppet agent --test --debug --noop

with that command you get all the output you can get.

excerpt puppet agent help
* --test:
  Enable the most common options used for testing. These are 'onetime',
  'verbose', 'ignorecache', 'no-daemonize', 'no-usecacheonfailure',
  'detailed-exitcodes', 'no-splay', and 'show_diff'.

NOTE: No need to include --verbose when you use the --test|-t switch, it implies the --verbose as well.

How to start debug mode from command prompt for apache tomcat server?

Inside catalina.bat set the port on which you wish to start the debugger

if not "%JPDA_ADDRESS%" == "" goto gotJpdaAddress
set JPDA_ADDRESS=9001

Then you can simply start the debugger with

catalina.bat jpda 

Now from Eclipse or IDEA select remote debugging and start start debugging by connecting to port 9001.

PHP Warning: Module already loaded in Unknown on line 0

I had the same issue after upgrading from Fedora Server 24 (PHP 5) to 25 (PHP 7). After investigation, I found that /etc/php.d/ had two different .ini files loading extension=geoip.so.

Previous version of distros had this file named 50-geoip.ini but the recent was changed to 40-geoip.ini, and I suspect that in the version-upgrade process the old hasn't been removed, while the new one has been created.

That was the actual case of the issue. After removing stray 50-geoip.ini from /etc/php.d/ and restarting httpd it just worked flawlessly.

PHP expects T_PAAMAYIM_NEKUDOTAYIM?

It’s the double colon operator :: (see list of parser tokens).

Convert sqlalchemy row object to python dict

Assuming the following functions will be added to the class User the following will return all key-value pairs of all columns:

def columns_to_dict(self):
    dict_ = {}
    for key in self.__mapper__.c.keys():
        dict_[key] = getattr(self, key)
    return dict_

unlike the other answers all but only those attributes of the object are returned which are Column attributes at class level of the object. Therefore no _sa_instance_state or any other attribute SQLalchemy or you add to the object are included. Reference

EDIT: Forget to say, that this also works on inherited Columns.

hybrid_propery extention

If you also want to include hybrid_property attributes the following will work:

from sqlalchemy import inspect
from sqlalchemy.ext.hybrid import hybrid_property

def publics_to_dict(self) -> {}:
    dict_ = {}
    for key in self.__mapper__.c.keys():
        if not key.startswith('_'):
            dict_[key] = getattr(self, key)

    for key, prop in inspect(self.__class__).all_orm_descriptors.items():
        if isinstance(prop, hybrid_property):
            dict_[key] = getattr(self, key)
    return dict_

I assume here that you mark Columns with an beginning _ to indicate that you want to hide them, either because you access the attribute by an hybrid_property or you simply do not want to show them. Reference

Tipp all_orm_descriptors also returns hybrid_method and AssociationProxy if you also want to include them.

Remarks to other answers

Every answer (like 1, 2 ) which based on the __dict__ attribute simply returns all attributes of the object. This could be much more attributes then you want. Like I sad this includes _sa_instance_state or any other attribute you define on this object.

Every answer (like 1, 2 ) which is based on the dict() function only works on SQLalchemy row objects returned by session.execute() not on the classes you define to work with, like the class User from the question.

The solving answer which is based on row.__table__.columns will definitely not work. row.__table__.columns contains the column names of the SQL Database. These can only be equal to the attributes name of the python object. If not you get an AttributeError. For answers (like 1, 2 ) based on class_mapper(obj.__class__).mapped_table.c it is the same.

In Python, how do I read the exif data for an image?

Here's the one that may be little easier to read. Hope this is helpful.

from PIL import Image
from PIL import ExifTags

exifData = {}
img = Image.open(picture.jpg)
exifDataRaw = img._getexif()
for tag, value in exifDataRaw.items():
    decodedTag = ExifTags.TAGS.get(tag, tag)
    exifData[decodedTag] = value

Issue with parsing the content from json file with Jackson & message- JsonMappingException -Cannot deserialize as out of START_ARRAY token

As said, JsonMappingException: out of START_ARRAY token exception is thrown by Jackson object mapper as it's expecting an Object {} whereas it found an Array [{}] in response.

A simpler solution could be replacing the method getLocations with:

public static List<Location> getLocations(InputStream inputStream) {
    ObjectMapper objectMapper = new ObjectMapper();
    try {
        TypeReference<List<Location>> typeReference = new TypeReference<>() {};
        return objectMapper.readValue(inputStream, typeReference);
    } catch (IOException e) {
        e.printStackTrace();
    }
    return null;
}

On the other hand, if you don't have a pojo like Location, you could use:

TypeReference<List<Map<String, Object>>> typeReference = new TypeReference<>() {};
return objectMapper.readValue(inputStream, typeReference);

What does HTTP/1.1 302 mean exactly?

As per the http status code definitions a 302 indicates a (temporary) redirect. "The requested resource resides temporarily under a different URI"

LEFT function in Oracle

There is no documented LEFT() function in Oracle. Find the full set here.

Probably what you have is a user-defined function. You can check that easily enough by querying the data dictionary:

select * from all_objects
where object_name = 'LEFT'

But there is the question of why the stored procedure works and the query doesn't. One possible solution is that the stored procedure is owned by another schema, which also owns the LEFT() function. They have granted rights on the procedure but not its dependencies. This works because stored procedures run with DEFINER privileges by default, so you run the stored procedure as if you were its owner.

If this is so then the data dictionary query I listed above won't help you: it will only return rows for objects you have rights on. In which case you will need to run the query as the stored procedure's owner or connect as a user with the rights to query DBA_OBJECTS instead.

how to convert object to string in java

maybe you benefit from converting it to JSON string

String jsonString = new com.google.gson.Gson().toJson(myObject);

in my case, I wanted to add an object to the response headers but you cant add objects to the headers,

so to solve this I convert my object to JSON string and in the client side I will return that string to JSON again

Does `anaconda` create a separate PYTHONPATH variable for each new environment?

No, the only thing that needs to be modified for an Anaconda environment is the PATH (so that it gets the right Python from the environment bin/ directory, or Scripts\ on Windows).

The way Anaconda environments work is that they hard link everything that is installed into the environment. For all intents and purposes, this means that each environment is a completely separate installation of Python and all the packages. By using hard links, this is done efficiently. Thus, there's no need to mess with PYTHONPATH because the Python binary in the environment already searches the site-packages in the environment, and the lib of the environment, and so on.

What is ANSI format?

Strictly speaking, there is no such thing as ANSI encoding. Colloquially the term ANSI is used for several different encodings:

  1. ISO 8859-1
  2. Windows CP1252
  3. Current system encoding on a Windows machine (in Win32 API terminology).

Using PI in python 2.7

To have access to stuff provided by math module, like pi. You need to import the module first:

import math
print (math.pi)

How do you change Background for a Button MouseOver in WPF?

This worked well for me.

Button Style

<Style x:Key="TransparentStyle" TargetType="{x:Type Button}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="Button">
                <Border>
                    <Border.Style>
                        <Style TargetType="{x:Type Border}">
                            <Style.Triggers>
                                <Trigger Property="IsMouseOver" Value="True">
                                    <Setter Property="Background" Value="DarkGoldenrod"/>
                                </Trigger>
                            </Style.Triggers>
                        </Style>
                    </Border.Style>
                    <Grid Background="Transparent">
                        <ContentPresenter></ContentPresenter>
                    </Grid>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

Button

<Button Style="{StaticResource TransparentStyle}" VerticalAlignment="Top" HorizontalAlignment="Right" Width="25" Height="25"
        Command="{Binding CloseWindow}">
    <Button.Content >
        <Grid Margin="0 0 0 0">
            <Path Data="M0,7 L10,17 M0,17 L10,7" Stroke="Blue" StrokeThickness="2" HorizontalAlignment="Center" Stretch="None" />
        </Grid>
    </Button.Content>
</Button>

Notes

  • The button displays a little blue cross, much like the one used to close a window.
  • By setting the background of the grid to "Transparent", it adds a hittest, which means that if the mouse is anywhere over the button, then it will work. Omit this tag, and the button will only light up if the mouse is over one of the vector lines in the icon (this is not very usable).

How can I specify the schema to run an sql file against in the Postgresql command line

You can create one file that contains the set schema ... statement and then include the actual file you want to run:

Create a file run_insert.sql:

set schema 'my_schema_01';
\i myInsertFile.sql

Then call this using:

psql -d myDataBase -a -f run_insert.sql

PHP refresh window? equivalent to F5 page reload?

Use JavaScript for this. You can do:

echo '
<script type="text/javascript">
   parent.window.location.reload(true);
</script>
';

In PHP and it will refresh the parent's frame page.

Removing "http://" from a string

Something like this ought to do:

$url = preg_replace("|^.+?://|", "", $url); 

Removes everything up to and including the ://

RecyclerView and java.lang.IndexOutOfBoundsException: Inconsistency detected. Invalid view holder adapter positionViewHolder in Samsung devices

another reason this problem happens is when you call these methods with wrong indexes (indexes which there has NOT happened insert or remove in them)

-notifyItemRangeRemoved

-notifyItemRemoved

-notifyItemRangeInserted

-notifyItemInserted

check indexe parameters to these methods and make sure they are precise and correct.

Xml serialization - Hide null values

You can create a function with the pattern ShouldSerialize{PropertyName} which tells the XmlSerializer if it should serialize the member or not.

For example, if your class property is called MyNullableInt you could have

public bool ShouldSerializeMyNullableInt() 
{
  return MyNullableInt.HasValue;
}

Here is a full sample

public class Person
{
  public string Name {get;set;}
  public int? Age {get;set;}
  public bool ShouldSerializeAge()
  {
    return Age.HasValue;
  }
}

Serialized with the following code

Person thePerson = new Person(){Name="Chris"};
XmlSerializer xs = new XmlSerializer(typeof(Person));
StringWriter sw = new StringWriter();
xs.Serialize(sw, thePerson);

Results in the followng XML - Notice there is no Age

<Person xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Name>Chris</Name>
</Person>

Case statement with multiple values in each 'when' block

You might take advantage of ruby's "splat" or flattening syntax.

This makes overgrown when clauses — you have about 10 values to test per branch if I understand correctly — a little more readable in my opinion. Additionally, you can modify the values to test at runtime. For example:

honda  = ['honda', 'acura', 'civic', 'element', 'fit', ...]
toyota = ['toyota', 'lexus', 'tercel', 'rx', 'yaris', ...]
...

if include_concept_cars
  honda += ['ev-ster', 'concept c', 'concept s', ...]
  ...
end

case car
when *toyota
  # Do something for Toyota cars
when *honda
  # Do something for Honda cars
...
end

Another common approach would be to use a hash as a dispatch table, with keys for each value of car and values that are some callable object encapsulating the code you wish to execute.

How do I convert hex to decimal in Python?

You could use a literal eval:

>>> ast.literal_eval('0xdeadbeef')
3735928559

Or just specify the base as argument to int:

>>> int('deadbeef', 16)
3735928559

A trick that is not well known, if you specify the base 0 to int, then Python will attempt to determine the base from the string prefix:

>>> int("0xff", 0)
255
>>> int("0o644", 0)
420
>>> int("0b100", 0)
4
>>> int("100", 0)
100

What is the best way to parse html in C#?

I found a project called Fizzler that takes a jQuery/Sizzler approach to selecting HTML elements. It's based on HTML Agility Pack. It's currently in beta and only supports a subset of CSS selectors, but it's pretty damn cool and refreshing to use CSS selectors over nasty XPath.

http://code.google.com/p/fizzler/

Checking for an empty field with MySQL

If you want to find all records that are not NULL, and either empty or have any number of spaces, this will work:

LIKE '%\ '

Make sure that there's a space after the backslash. More info here: http://dev.mysql.com/doc/refman/5.0/en/string-comparison-functions.html

Jquery click not working with ipad

Probably rather than defining both the events click and touch you could define a an handler which will look if the device will work with click or touch.

var handleClick= 'ontouchstart' in document.documentElement ? 'touchstart': 'click';
$(document).on(handleClick,'.button',function(){
alert('Click is now working with touch and click both');
});

Document Root PHP

The Easiest way to do it is to have good site structure and write it as a constant.

DEFINE("BACK_ROOT","/var/www/");

How do I sort a VARCHAR column in SQL server that contains numbers?

SELECT FIELD FROM TABLE
ORDER BY 
  isnumeric(FIELD) desc, 
  CASE ISNUMERIC(test) 
    WHEN 1 THEN CAST(CAST(test AS MONEY) AS INT)
    ELSE NULL 
  END,
  FIELD

As per this link you need to cast to MONEY then INT to avoid ordering '$' as a number.

Where can I get Google developer key

You should be able to generate a Youtube API key there.

The recommended way to authorize your API call is to use OAuth 2.0 (without API key), as pointed by the documentation an API key is only necessary when using OAuth 1.0 credentials.

The API key for your application can be found in the Google APIs Console in API Access > Simple API.

HTML "overlay" which allows clicks to fall through to elements behind it

My team ran into this issue and resolved it very nicely.

  • add a class "passthrough" or something to each element you want clickable and which is under the overlay.
  • for each ".passthrough" element append a div and position it exactly on top of its parent. add class "element-overlay" to this new div.
  • The ".element-overlay" css should have a high z-index (above the page's overlay), and the elements should be transparent.

This should resolve your problem as the events on the ".element-overlay" should bubble up to ".passthrough". If you still have problems (we did not see any so far) you can play around with the binding.

This is an enhancement to @jvenema's solution.

The nice thing about this is that

  • you don't pass through ALL events to ALL elements. Just the ones you want. (resolved @jvenema's argument)
  • All events will work properly. (hover for example).

If you have any problems please let me know so I can elaborate.

Makefile: How to correctly include header file and its directory?

Try INC_DIR=../ ../StdCUtil.

Then, set CCFLAGS=-c -Wall $(addprefix -I,$(INC_DIR))

EDIT: Also, modify your #include to be #include <StdCUtil/split.h> so that the compiler knows to use -I rather than local path of the .cpp using the #include.

How to remove "href" with Jquery?

If you want your anchor to still appear to be clickable:

$("a").removeAttr("href").css("cursor","pointer");

And if you wanted to remove the href from only anchors with certain attributes (eg ones that just have a hash mark as the href - this can be useful in asp.net)

$("a[href='#']").removeAttr("href").css("cursor","pointer");

Is there a MySQL option/feature to track history of changes to records?

You could create triggers to solve this. Here is a tutorial to do so (archived link).

Setting constraints and rules in the database is better than writing special code to handle the same task since it will prevent another developer from writing a different query that bypasses all of the special code and could leave your database with poor data integrity.

For a long time I was copying info to another table using a script since MySQL didn’t support triggers at the time. I have now found this trigger to be more effective at keeping track of everything.

This trigger will copy an old value to a history table if it is changed when someone edits a row. Editor ID and last mod are stored in the original table every time someone edits that row; the time corresponds to when it was changed to its current form.

DROP TRIGGER IF EXISTS history_trigger $$

CREATE TRIGGER history_trigger
BEFORE UPDATE ON clients
    FOR EACH ROW
    BEGIN
        IF OLD.first_name != NEW.first_name
        THEN
                INSERT INTO history_clients
                    (
                        client_id    ,
                        col          ,
                        value        ,
                        user_id      ,
                        edit_time
                    )
                    VALUES
                    (
                        NEW.client_id,
                        'first_name',
                        NEW.first_name,
                        NEW.editor_id,
                        NEW.last_mod
                    );
        END IF;

        IF OLD.last_name != NEW.last_name
        THEN
                INSERT INTO history_clients
                    (
                        client_id    ,
                        col          ,
                        value        ,
                        user_id      ,
                        edit_time
                    )
                    VALUES
                    (
                        NEW.client_id,
                        'last_name',
                        NEW.last_name,
                        NEW.editor_id,
                        NEW.last_mod
                    );
        END IF;

    END;
$$

Another solution would be to keep an Revision field and update this field on save. You could decide that the max is the newest revision, or that 0 is the most recent row. That's up to you.

RichTextBox (WPF) does not have string property "Text"

Using two extension methods, this becomes very easy:

public static class Ext
{
    public static void SetText(this RichTextBox richTextBox, string text)
    {
        richTextBox.Document.Blocks.Clear();
        richTextBox.Document.Blocks.Add(new Paragraph(new Run(text)));
    }

    public static string GetText(this RichTextBox richTextBox)
    {
        return new TextRange(richTextBox.Document.ContentStart,
            richTextBox.Document.ContentEnd).Text;
    }
}

intelliJ IDEA 13 error: please select Android SDK

check if you have installed all the add-ons that are necessary. Also I recommend you to use a real android phone for debugging. It's better, It's real and faster.

Shortest way to print current year in a website

according to chrome audit

For users on slow connections, external scripts dynamically injected via document.write() can delay page load by tens of seconds.

https://web.dev/no-document-write/?utm_source=lighthouse&utm_medium=devtools

so solution without errors is:

(new Date).getFullYear();

Rollback one specific migration in Laravel

Another alternative to those mentioned if you need to do this a bunch of times with the same migration(s). Personally I think this adds a lot of flexibility to your migrations.

Add database/migrations to your autoload object in your composer.json like this:

"autoload": {
        "psr-4": {
            "App\\": "app/"
        },
        "classmap": [
            "database/seeds",
            "database/factories",
            "database/support",
            "database/migrations" // add this line
        ]
    },

Then add namespace Database\Migrations; to all of your migration files.

Then run $ composer dump-autoload to refresh your composer.lock file.

Then, assuming your class name for the migration is AlterTableWebDirectories, you can create a command like this:

$ php artisan make:command DropAlterTableWebDirectories

And write this logic in your handle() method:

public function handle {
   (new AlterTableWebDirectories)->down();
   DB::raw("delete from migrations where migration like '%alter_table_web_directories%'");
}

This will do exactly what you want. If you want to decrement the migration count instead of deleting it, you can probably figure out how to change the DB:raw command.

This command could be extended to allow you to dynamically choose which migration you're dropping it by passing an argument into the command.

Then when you're reading to migrate that file again, you can just run php artisan migrate and it will only migrate that one.

This process allows you to make specific changes to migrations without having to do a full refresh and seed each time.

Personally I need to do that a lot because my seeds are rather large.

Can table columns with a Foreign Key be NULL?

Another way around this would be to insert a DEFAULT element in the other table. For example, any reference to uuid=00000000-0000-0000-0000-000000000000 on the other table would indicate no action. You also need to set all the values for that id to be "neutral", e.g. 0, empty string, null in order to not affect your code logic.

The breakpoint will not currently be hit. No symbols have been loaded for this document in a Silverlight application

I've just resolved this issue according to Deploying Silverlight Applications. (This answer is a duplicate of some others but I'll attempt to explain it more thoroughly.)

The problem is most likely that your Silverlight application is not being deployed properly to your web application on build / startup. This is a referencing problem - it's simple to understand but not obvious the first time you encounter it.

Just like any other project reference, the referenced project's output should be copied to the referencing project's bin folder in order to debug. For class libraries this happens when you right click and select 'Add Reference...'. For Silverlight, you should add a reference through Project Properties.

  • Right click your project, and select 'Properties'
  • Select the 'Silverlight Applications' tab on the left
  • Press the 'Add...' button and select your Silverlight project from the dialogue box

This adds a reference to the Silverlight application from your hosting web app, and ensures that the xap file will be copied to the web app on build or deploy. That means that the current Silverlight app and its debug files are inside the application being debugged, and you'll be able to step through the code.

How can I check if character in a string is a letter? (Python)

data = "abcdefg hi j 12345"

digits_count = 0
letters_count = 0
others_count = 0

for i in userinput:

    if i.isdigit():
        digits_count += 1 
    elif i.isalpha():
        letters_count += 1
    else:
        others_count += 1

print("Result:")        
print("Letters=", letters_count)
print("Digits=", digits_count)

Output:

Please Enter Letters with Numbers:
abcdefg hi j 12345
Result:
Letters = 10
Digits = 5

By using str.isalpha() you can check if it is a letter.

How can I bind a background color in WPF/XAML?

Here you've got a copy-paste code:

class NameToBackgroundConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if(value.ToString() == "System")
            {
                return new SolidColorBrush(System.Windows.Media.Colors.Aqua);
            }else
            {
                return new SolidColorBrush(System.Windows.Media.Colors.Blue);
            }
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            return null;
        }
    }

How to play .wav files with java

Finally I managed to do the following and it works fine

import java.io.File;
import java.io.IOException;

import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.LineUnavailableException;
import javax.sound.sampled.SourceDataLine;

public class MakeSound {

    private final int BUFFER_SIZE = 128000;
    private File soundFile;
    private AudioInputStream audioStream;
    private AudioFormat audioFormat;
    private SourceDataLine sourceLine;

    /**
     * @param filename the name of the file that is going to be played
     */
    public void playSound(String filename){

        String strFilename = filename;

        try {
            soundFile = new File(strFilename);
        } catch (Exception e) {
            e.printStackTrace();
            System.exit(1);
        }

        try {
            audioStream = AudioSystem.getAudioInputStream(soundFile);
        } catch (Exception e){
            e.printStackTrace();
            System.exit(1);
        }

        audioFormat = audioStream.getFormat();

        DataLine.Info info = new DataLine.Info(SourceDataLine.class, audioFormat);
        try {
            sourceLine = (SourceDataLine) AudioSystem.getLine(info);
            sourceLine.open(audioFormat);
        } catch (LineUnavailableException e) {
            e.printStackTrace();
            System.exit(1);
        } catch (Exception e) {
            e.printStackTrace();
            System.exit(1);
        }

        sourceLine.start();

        int nBytesRead = 0;
        byte[] abData = new byte[BUFFER_SIZE];
        while (nBytesRead != -1) {
            try {
                nBytesRead = audioStream.read(abData, 0, abData.length);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (nBytesRead >= 0) {
                @SuppressWarnings("unused")
                int nBytesWritten = sourceLine.write(abData, 0, nBytesRead);
            }
        }

        sourceLine.drain();
        sourceLine.close();
    }
}

BigDecimal equals() versus compareTo()

You can also compare with double value

BigDecimal a= new BigDecimal("1.1"); BigDecimal b =new BigDecimal("1.1");
System.out.println(a.doubleValue()==b.doubleValue());

How to activate a specific worksheet in Excel?

I would recommend you to use worksheet's index instead of using worksheet's name, in this way you can also loop through sheets "dynamically"

for i=1 to thisworkbook.sheets.count
 sheets(i).activate
'You can add more code 
with activesheet
 'Code...
end with
next i

It will also, improve performance.

APR based Apache Tomcat Native library was not found on the java.library.path?

For Ubntu Users

 1. Install compilers
    #sudo apt-get install make
    #sudo apt-get install gcc

    2. Install openssl and development libraries
    #sudo apt-get install openssl
    #sudo apt-get install libssl-dev
    3. Install the APR package (Downloaded from http://apr.apache.org/)

    #tar -xzf apr-1.4.6.tar.gz
    #cd apr-1.4.6/
    #sudo ./configure
    #sudo make
    #sudo make install

    You should see the compiled file as
    /usr/local/apr/lib/libapr-1.a

    4. Download, compile and install Tomcat Native sourse package
    tomcat-native-1.1.27-src.tar.gz

    Extract the archive into some folder

    #tar -xzf tomcat-native-1.1.27-src.tar.gz
    #cd tomcat-native-1.1.27-src/jni/native
    #JAVA_HOME=/usr/lib/jvm/jdk1.7.0_21/
    #sudo ./configure --with-apr=/usr/local/apr --with-java-home=$JAVA_HOME
    #sudo make
    #sudo make install

    Now I have compiled Tomcat Native library in /usr/local/apr/libtcnative-1.so.0.1.27 and symbolic link file /usr/local/apr/@libtcnative-1.so pointed to the library

    5. Create or edit the $CATALINA_HOME/bin/setenv.sh file with following lines :
    export LD_LIBRARY_PATH='$LD_LIBRARY_PATH:/usr/local/apr/lib'

    6. Restart tomcat and see the desired result:

Pass table as parameter into sql server UDF

Unfortunately, there is no simple way in SQL Server 2005. Lukasz' answer is correct for SQL Server 2008 though and the feature is long overdue

Any solution would involve temp tables, or passing in xml/CSV and parsing in the UDF. Example: change to xml, parse in udf

DECLARE @psuedotable xml

SELECT
    @psuedotable = ...
FROM
    ...
FOR XML ...

SELECT ... dbo.MyUDF (@psuedotable)

What do you want to do in the bigger picture though? There may be another way to do this...

Edit: Why not pass in the query as a string and use a stored proc with output parameter

Note: this is an untested bit of code, and you'd need to think about SQL injection etc. However, it also satisfies your "one column" requirement and should help you along

CREATE PROC dbo.ToCSV (
    @MyQuery varchar(2000),
    @CSVOut varchar(max)
)
AS
SET NOCOUNT ON

CREATE TABLE #foo (bar varchar(max))

INSERT #foo
EXEC (@MyQuery)

SELECT
    @CSVOut = SUBSTRING(buzz, 2, 2000000000)
FROM
    (
    SELECT 
        bar -- maybe CAST(bar AS varchar(max))??
    FROM 
        #foo
    FOR XML PATH (',')
    ) fizz(buzz)
GO

Python 3.6 install win32api?

Take a look at this answer: ImportError: no module named win32api

You can use

pip install pypiwin32

Can I set up HTML/Email Templates with ASP.NET?

Note that the aspx and ascx solutions require a current HttpContext, so cannot be used asynchronously (eg in threads) without a lot of work.

How do I restrict a float value to only two places after the decimal point in C?

I made this macro for rounding float numbers. Add it in your header / being of file

#define ROUNDF(f, c) (((float)((int)((f) * (c))) / (c)))

Here is an example:

float x = ROUNDF(3.141592, 100)

x equals 3.14 :)

How can I get the last day of the month in C#?

public static class DateTimeExtensions
{
    public static DateTime LastDayOfMonth(this DateTime date)
    {
        return date.AddDays(1-(date.Day)).AddMonths(1).AddDays(-1);
    }
}

How to get the absolute coordinates of a view

First you have to get the localVisible rectangle of the view

For eg:

Rect rectf = new Rect();

//For coordinates location relative to the parent
anyView.getLocalVisibleRect(rectf);

//For coordinates location relative to the screen/display
anyView.getGlobalVisibleRect(rectf);

Log.d("WIDTH        :", String.valueOf(rectf.width()));
Log.d("HEIGHT       :", String.valueOf(rectf.height()));
Log.d("left         :", String.valueOf(rectf.left));
Log.d("right        :", String.valueOf(rectf.right));
Log.d("top          :", String.valueOf(rectf.top));
Log.d("bottom       :", String.valueOf(rectf.bottom));

Hope this will help

How do I pass variables and data from PHP to JavaScript?

<script>
  var jsvar = <?php echo json_encode($PHPVar); ?>;
</script>

json_encode() requires:

  • PHP 5.2.0 or more
  • $PHPVar encoded as UTF-8, Unicode.

GridView VS GridLayout in Android Apps

A GridView is a ViewGroup that displays items in two-dimensional scrolling grid. The items in the grid come from the ListAdapter associated with this view.

This is what you'd want to use (keep using). Because a GridView gets its data from a ListAdapter, the only data loaded in memory will be the one displayed on screen. GridViews, much like ListViews reuse and recycle their views for better performance.

Whereas a GridLayout is a layout that places its children in a rectangular grid.

It was introduced in API level 14, and was recently backported in the Support Library. Its main purpose is to solve alignment and performance problems in other layouts. Check out this tutorial if you want to learn more about GridLayout.

SQLAlchemy: print the actual query

This code is based on brilliant existing answer from @bukzor. I just added custom render for datetime.datetime type into Oracle's TO_DATE().

Feel free to update code to suit your database:

import decimal
import datetime

def printquery(statement, bind=None):
    """
    print a query, with values filled in
    for debugging purposes *only*
    for security, you should always separate queries from their values
    please also note that this function is quite slow
    """
    import sqlalchemy.orm
    if isinstance(statement, sqlalchemy.orm.Query):
        if bind is None:
            bind = statement.session.get_bind(
                    statement._mapper_zero_or_none()
            )
        statement = statement.statement
    elif bind is None:
        bind = statement.bind 

    dialect = bind.dialect
    compiler = statement._compiler(dialect)
    class LiteralCompiler(compiler.__class__):
        def visit_bindparam(
                self, bindparam, within_columns_clause=False, 
                literal_binds=False, **kwargs
        ):
            return super(LiteralCompiler, self).render_literal_bindparam(
                    bindparam, within_columns_clause=within_columns_clause,
                    literal_binds=literal_binds, **kwargs
            )
        def render_literal_value(self, value, type_):
            """Render the value of a bind parameter as a quoted literal.

            This is used for statement sections that do not accept bind paramters
            on the target driver/database.

            This should be implemented by subclasses using the quoting services
            of the DBAPI.

            """
            if isinstance(value, basestring):
                value = value.replace("'", "''")
                return "'%s'" % value
            elif value is None:
                return "NULL"
            elif isinstance(value, (float, int, long)):
                return repr(value)
            elif isinstance(value, decimal.Decimal):
                return str(value)
            elif isinstance(value, datetime.datetime):
                return "TO_DATE('%s','YYYY-MM-DD HH24:MI:SS')" % value.strftime("%Y-%m-%d %H:%M:%S")

            else:
                raise NotImplementedError(
                            "Don't know how to literal-quote value %r" % value)            

    compiler = LiteralCompiler(dialect, statement)
    print compiler.process(statement)

Post-increment and pre-increment within a 'for' loop produce same output

Because in either case the increment is done after the body of the loop and thus doesn't affect any of the calculations of the loop. If the compiler is stupid, it might be slightly less efficient to use post-increment (because normally it needs to keep a copy of the pre value for later use), but I would expect any differences to be optimized away in this case.

It might be handy to think of how the for loop is implemented, essentially translated into a set of assignments, tests, and branch instructions. In pseudo-code the pre-increment would look like:

      set i = 0
test: if i >= 5 goto done
      call printf,"%d",i
      set i = i + 1
      goto test
done: nop

Post-increment would have at least another step, but it would be trivial to optimize away

      set i = 0
test: if i >= 5 goto done
      call printf,"%d",i
      set j = i   // store value of i for later increment
      set i = j + 1  // oops, we're incrementing right-away
      goto test
done: nop

Extract part of a regex match

Use ( ) in regexp and group(1) in python to retrieve the captured string (re.search will return None if it doesn't find the result, so don't use group() directly):

title_search = re.search('<title>(.*)</title>', html, re.IGNORECASE)

if title_search:
    title = title_search.group(1)

How to Ignore "Duplicate Key" error in T-SQL (SQL Server)

If by "Ignore Duplicate Error statments", to abort the current statement and continue to the next statement without aborting the trnsaction then just put BEGIN TRY.. END TRY around each statement:

BEGIN TRY
    INSERT ...
END TRY
BEGIN CATCH /*required, but you dont have to do anything */ END CATCH
...

How do I syntax check a Bash script without running it?

null command [colon] also useful when debugging to see variable's value

set -x
for i in {1..10}; do
    let i=i+1
    : i=$i
done
set - 

How to find an object in an ArrayList by property

Following with Oleg answer, if you want to find ALL objects in a List filtered by a property, you could do something like:

//Search into a generic list ALL items with a generic property
public final class SearchTools {
       public static <T> List<T> findByProperty(Collection<T> col, Predicate<T> filter) {
           List<T> filteredList = (List<T>) col.stream().filter(filter).collect(Collectors.toList());
           return filteredList;
     }

//Search in the list "listItems" ALL items of type "Item" with the specific property "iD_item=itemID"
public static final class ItemTools {
         public static List<Item> findByItemID(Collection<Item> listItems, String itemID) {
             return SearchTools.findByProperty(listItems, item -> itemID.equals(item.getiD_Item()));
         }
     }
}

and similarly if you want to filter ALL items in a HashMap with a certain Property

//Search into a MAP ALL items with a given property
public final class SearchTools {
       public static <T> HashMap<String,T> filterByProperty(HashMap<String,T> completeMap, Predicate<? super Map.Entry<String,T>> filter) {
           HashMap<String,T> filteredList = (HashMap<String,T>) completeMap.entrySet().stream()
                                .filter(filter)
                                .collect(Collectors.toMap(map -> map.getKey(), map -> map.getValue()));
           return filteredList;
     }

     //Search into the MAP ALL items with specific properties
public static final class ItemTools {

        public static HashMap<String,Item> filterByParentID(HashMap<String,Item> mapItems, String parentID) {
            return SearchTools.filterByProperty(mapItems, mapItem -> parentID.equals(mapItem.getValue().getiD_Parent()));
        }

        public static HashMap<String,Item> filterBySciName(HashMap<String,Item> mapItems, String sciName) {
            return SearchTools.filterByProperty(mapItems, mapItem -> sciName.equals(mapItem.getValue().getSciName()));
        }
    }

ngModel cannot be used to register form controls with a parent formGroup directive

This error apears when you have some form controls (like Inputs, Selects, etc) in your form group tags with no formControlName property.

Those examples throws the error:

<form [formGroup]="myform">
    <input type="text">
    <input type="text" [ngmodel]="nameProperty">
    <input type="text" [formGroup]="myform" [name]="name">
</fom>

There are two ways, the stand alone:

<form [formGroup]="myform">
    <input type="text" [ngModelOptions]="{standalone: true}">
    <input type="text" [ngmodel]="nameProperty" [ngModelOptions]="{standalone: true}">
    <!-- input type="text" [formGroup]="myform" [name]="name" --> <!-- no works with standalone --
</form>

Or including it into the formgroup

<form [formGroup]="myform">
    <input type="text" formControlName="field1">
    <input type="text" formControlName="nameProperty">
    <input type="text" formControlName="name">
</fom>

The last one implies to define them in the initialization formGroup

this.myForm =  new FormGroup({
    field1: new FormControl(''),
    nameProperty: new FormControl(''),
    name: new FormControl('')
});

Magento Product Attribute Get Value

You don't have to load the whole product. Magentos collections are very powerful and smart.

$collection = Mage::getModel('catalog/product')->getCollection();
$collection->addAttributeToFilter('entity_id', $product->getId());
$collection->addAttributeToSelect('manufacturer');
$product = $collection->getFirstItem();
$manufacturer = $product->getAttributeText('manufacturer');

At the moment you call getFirstItem() the query will be executed and the result product is very minimal:

[status] => 1
[entity_id] => 38901
[type_id] => configurable
[attribute_set_id] => 9
[manufacturer] => 492
[manufacturer_value] => JETTE
[is_salable] => 1
[stock_item (Varien_Object)] => Array
    (
        [is_in_stock] => 1
    )

Enum String Name from Value

For getting the String value [Name]:

EnumDisplayStatus enumDisplayStatus = (EnumDisplayStatus)GetDBValue();
string stringValue = $"{enumDisplayStatus:G}"; 

And for getting the enum value:

string stringValue = $"{enumDisplayStatus:D}";
SetDBValue(Convert.ToInt32(stringValue ));

Cancel split window in Vim

I found that ctrl + w to the window you want to close, then just do :q. This works for me.

Namespace not recognized (even though it is there)

Crazy. I know.

Tried all options here. Restarting, cleaning, manually checking in generated DLLs (this is invaluable to understanding if it's actually yourself that messed up).

I got it to work by setting the Verbosity of MSBuild to "Detailed" in Options.

How to find which version of Oracle is installed on a Linux server (In terminal)

I solved this in about 1 minute by just reading the startup script (in my case /etc/init.d/oracle-xe):

less /etc/init.d/oracle-xe

At almost the beginning of the file I found:

ORACLE_HOME=[PATH_TO_INSTALLATION_INCLUDING_VERSION_NUMBER]

This was the quickest solution for me because I knew where the script was located, and that it is used for starting/restarting the server.

Of course, this relies on that the version number actually corresponds to the actual server version, which it should for a correctly installed instance.

html/css buttons that scroll down to different div sections on a webpage

HTML

<a href="#top">Top</a>
<a href="#middle">Middle</a>
<a href="#bottom">Bottom</a>
<div id="top"><a href="top"></a>Top</div>
<div id="middle"><a href="middle"></a>Middle</div>
<div id="bottom"><a href="bottom"></a>Bottom</div>

CSS

#top,#middle,#bottom{
    height: 600px;
    width: 300px;
    background: green; 
}

Example http://jsfiddle.net/x4wDk/

$watch an object

For anyone that wants to watch for a change to an object within an array of objects, this seemed to work for me (as the other solutions on this page didn't):

function MyController($scope) {

    $scope.array = [
        data1: {
            name: 'name',
            surname: 'surname'
        },
        data2: {
            name: 'name',
            surname: 'surname'
        },
    ]


    $scope.$watch(function() {
        return $scope.data,
    function(newVal, oldVal){
        console.log(newVal, oldVal);
    }, true);

what does "dead beef" mean?

People normally use it to indicate dummy values. I think that it primarily was used before the idea of NULL pointers.

how to save canvas as png image?

I had this problem and this is the best solution without any external or additional script libraries: In Javascript tags or file create this function: We assume here that canvas is your canvas:

function download(){
        var download = document.getElementById("download");
        var image = document.getElementById("canvas").toDataURL("image/png")
                    .replace("image/png", "image/octet-stream");
        download.setAttribute("href", image);

    }

In the body part of your HTML specify the button:

<a id="download" download="image.png"><button type="button" onClick="download()">Download</button></a>

This is working and download link looks like a button. Tested in Firefox and Chrome.

Is right click a Javascript event?

have a look at the following jQuery code:

$("#myId").mousedown(function(ev){
      if(ev.which == 3)
      {
            alert("Right mouse button clicked on element with id myId");
      }
});

The value of which will be:

  • 1 for the left button
  • 2 for the middle button
  • 3 for the right button

Multiple maven repositories in one gradle file

you have to do like this in your project level gradle file

allprojects {
    repositories {
        jcenter()
        maven { url "http://dl.appnext.com/" }
        maven { url "https://maven.google.com" }
    }
}

search in java ArrayList

Customer findCustomerByid(int id){
    for (int i=0; i<this.customers.size(); i++) {
        Customer customer = this.customers.get(i);
        if (customer.getId() == id){
             return customer;
        }
    }
    return null; // no Customer found with this ID; maybe throw an exception
}

Richtextbox wpf binding

This VB.Net version works for my situation. I removed thread collection semaphore, instead using RemoveHandler and AddHandler. Also, since a FlowDocument can only be bound to one RichTextBox at a time, I put in a check that the RichTextBox's IsLoaded=True. Let's begin with how I used the class in a MVVM app which uses ResourceDictionary instead of Window.

    ' Loaded and Unloaded events seems to be the only way to initialize a control created from a Resource Dictionary
' Loading document here because Loaded is the last available event to create a document
Private Sub Rtb_Loaded(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs)
    ' only good place to initialize RichTextBox.Document with DependencyProperty
    Dim rtb As RichTextBox = DirectCast(sender, RichTextBox)
    Try
        rtb.Document = RichTextBoxHelper.GetDocumentXaml(rtb)
    Catch ex As Exception
        Debug.WriteLine("Rtb_Loaded: Message:" & ex.Message)
    End Try
End Sub

' Loaded and Unloaded events seems to be the only way to initialize a control created from a Resource Dictionary
' Free document being held by RichTextBox.Document by assigning New FlowDocument to RichTextBox.Document. Otherwise we'll see an of "Document belongs to another RichTextBox"
Private Sub Rtb_Unloaded(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs)
    Dim rtb As RichTextBox = DirectCast(sender, RichTextBox)
    Dim fd As New FlowDocument
    RichTextBoxHelper.SetDocumentXaml(rtb, fd)
    Try
        rtb.Document = fd
    Catch ex As Exception
        Debug.WriteLine("PoemDocument.PoemDocumentView.PoemRtb_Unloaded: Message:" & ex.Message)
    End Try
End Sub

Public Class RichTextBoxHelper
    Inherits DependencyObject

    Public Shared Function GetDocumentXaml(ByVal depObj As DependencyObject) As FlowDocument
        Return depObj.GetValue(DocumentXamlProperty)
    End Function

    Public Shared Sub SetDocumentXaml(ByVal depObj As DependencyObject, ByVal value As FlowDocument)
        depObj.SetValue(DocumentXamlProperty, value)
    End Sub

    Public Shared ReadOnly DocumentXamlProperty As DependencyProperty = DependencyProperty.RegisterAttached("DocumentXaml", GetType(FlowDocument), GetType(RichTextBoxHelper), New FrameworkPropertyMetadata(Nothing, FrameworkPropertyMetadataOptions.AffectsRender Or FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, Sub(depObj, e)
                                                                                                                                                                                                                                                                                                                                   RegisterIt(depObj, e)
                                                                                                                                                                                                                                                                                                                               End Sub))


    Private Shared Sub RegisterIt(ByVal depObj As System.Windows.DependencyObject, ByVal e As System.Windows.DependencyPropertyChangedEventArgs)
        Dim rtb As RichTextBox = DirectCast(depObj, RichTextBox)
        If rtb.IsLoaded Then
            RemoveHandler rtb.TextChanged, AddressOf TextChanged
            Try
                rtb.Document = GetDocumentXaml(rtb)
            Catch ex As Exception
                Debug.WriteLine("RichTextBoxHelper.RegisterIt: ex:" & ex.Message)
                rtb.Document = New FlowDocument()
            End Try
            AddHandler rtb.TextChanged, AddressOf TextChanged
        Else
            Debug.WriteLine("RichTextBoxHelper: Unloaded control ignored:" & rtb.Name)
        End If
    End Sub

    ' When a RichTextBox Document changes, update the DependencyProperty so they're in sync.
    Private Shared Sub TextChanged(ByVal sender As Object, ByVal e As TextChangedEventArgs)
        Dim rtb As RichTextBox = TryCast(sender, RichTextBox)
        If rtb IsNot Nothing Then
            SetDocumentXaml(sender, rtb.Document)
        End If
    End Sub

End Class

jQuery trigger event when click outside the element

try these..

$(document).click(function(evt) {
    var target = evt.target.className;
    var inside = $(".menuWraper");
    //alert($(target).html());
    if ($.trim(target) != '') {
        if ($("." + target) != inside) {
            alert("bleep");
        }
    }
});

Function or sub to add new row and data to table

Minor variation of phillfri's answer which was already a variation of Geoff's answer: I added the ability to handle completely empty tables that contain no data for the Array Code.

Sub AddDataRow(tableName As String, NewData As Variant)
    Dim sheet As Worksheet
    Dim table As ListObject
    Dim col As Integer
    Dim lastRow As Range

    Set sheet = Range(tableName).Parent
    Set table = sheet.ListObjects.Item(tableName)

    'First check if the last row is empty; if not, add a row
    If table.ListRows.Count > 0 Then
        Set lastRow = table.ListRows(table.ListRows.Count).Range
        If Application.CountBlank(lastRow) < lastRow.Columns.Count Then
            table.ListRows.Add
        End If
    End If

    'Iterate through the last row and populate it with the entries from values()
    If table.ListRows.Count = 0 Then 'If table is totally empty, set lastRow as first entry
        table.ListRows.Add Position:=1
        Set lastRow = table.ListRows(1).Range
    Else
        Set lastRow = table.ListRows(table.ListRows.Count).Range
    End If
    For col = 1 To lastRow.Columns.Count
        If col <= UBound(NewData) + 1 Then lastRow.Cells(1, col) = NewData(col - 1)
    Next col
End Sub

Sending POST data without form

Send your data with SESSION rather than post.

session_start();
$_SESSION['foo'] = "bar";

On the page where you recieve the request, if you absolutely need POST data (some weird logic), you can do this somwhere at the beginning:

$_POST['foo'] = $_SESSION['foo'];

The post data will be valid just the same as if it was sent with POST.

Then destroy the session (or just unset the fields if you need the session for other purposes).

It is important to destroy a session or unset the fields, because unlike POST, SESSION will remain valid until you explicitely destroy it or until the end of browser session. If you don't do it, you can observe some strange results. For example: you use sesson for filtering some data. The user switches the filter on and gets filtered data. After a while, he returns to the page and expects the filter to be reset, but it's not: he still sees filtered data.

Windows equivalent of OS X Keychain?

Actually, looking through MSDN, the functions they recommend using (instead of Protected Storage) are:

  • CryptProtectData
  • CryptUnprotectData

The link for CryptProtectData is at CryptProtectData function.

Should I use the Reply-To header when sending emails as a service to others?

After reading all of this, I might just embed a hyperlink in the email body like this:

To reply to this email, click here <a href="mailto:...">[email protected]</a>

How can I read input from the console using the Scanner class in Java?

There are several ways to get input from the user. Here in this program we will take the Scanner class to achieve the task. This Scanner class comes under java.util, hence the first line of the program is import java.util.Scanner; which allows the user to read values of various types in Java. The import statement line should have to be in the first line the java program, and we proceed further for code.

in.nextInt(); // It just reads the numbers

in.nextLine(); // It get the String which user enters

To access methods in the Scanner class create a new scanner object as "in". Now we use one of its method, that is "next". The "next" method gets the string of text that a user enters on the keyboard.

Here I'm using in.nextLine(); to get the String which the user enters.

import java.util.Scanner;

class GetInputFromUser {
    public static void main(String args[]) {
        int a;
        float b;
        String s;

        Scanner in = new Scanner(System.in);
        System.out.println("Enter a string");
        s = in.nextLine();
        System.out.println("You entered string " + s);

        System.out.println("Enter an integer");
        a = in.nextInt();
        System.out.println("You entered integer " + a);

        System.out.println("Enter a float");
        b = in.nextFloat();
        System.out.println("You entered float " + b);
    }
}

Finding all possible permutations of a given string in python

itertools.permutations is good, but it doesn't deal nicely with sequences that contain repeated elements. That's because internally it permutes the sequence indices and is oblivious to the sequence item values.

Sure, it's possible to filter the output of itertools.permutations through a set to eliminate the duplicates, but it still wastes time generating those duplicates, and if there are several repeated elements in the base sequence there will be lots of duplicates. Also, using a collection to hold the results wastes RAM, negating the benefit of using an iterator in the first place.

Fortunately, there are more efficient approaches. The code below uses the algorithm of the 14th century Indian mathematician Narayana Pandita, which can be found in the Wikipedia article on Permutation. This ancient algorithm is still one of the fastest known ways to generate permutations in order, and it is quite robust, in that it properly handles permutations that contain repeated elements.

def lexico_permute_string(s):
    ''' Generate all permutations in lexicographic order of string `s`

        This algorithm, due to Narayana Pandita, is from
        https://en.wikipedia.org/wiki/Permutation#Generation_in_lexicographic_order

        To produce the next permutation in lexicographic order of sequence `a`

        1. Find the largest index j such that a[j] < a[j + 1]. If no such index exists, 
        the permutation is the last permutation.
        2. Find the largest index k greater than j such that a[j] < a[k].
        3. Swap the value of a[j] with that of a[k].
        4. Reverse the sequence from a[j + 1] up to and including the final element a[n].
    '''

    a = sorted(s)
    n = len(a) - 1
    while True:
        yield ''.join(a)

        #1. Find the largest index j such that a[j] < a[j + 1]
        for j in range(n-1, -1, -1):
            if a[j] < a[j + 1]:
                break
        else:
            return

        #2. Find the largest index k greater than j such that a[j] < a[k]
        v = a[j]
        for k in range(n, j, -1):
            if v < a[k]:
                break

        #3. Swap the value of a[j] with that of a[k].
        a[j], a[k] = a[k], a[j]

        #4. Reverse the tail of the sequence
        a[j+1:] = a[j+1:][::-1]

for s in lexico_permute_string('data'):
    print(s)

output

aadt
aatd
adat
adta
atad
atda
daat
data
dtaa
taad
tada
tdaa

Of course, if you want to collect the yielded strings into a list you can do

list(lexico_permute_string('data'))

or in recent Python versions:

[*lexico_permute_string('data')]

Is floating point math broken?

Imagine working in base ten with, say, 8 digits of accuracy. You check whether

1/3 + 2 / 3 == 1

and learn that this returns false. Why? Well, as real numbers we have

1/3 = 0.333.... and 2/3 = 0.666....

Truncating at eight decimal places, we get

0.33333333 + 0.66666666 = 0.99999999

which is, of course, different from 1.00000000 by exactly 0.00000001.


The situation for binary numbers with a fixed number of bits is exactly analogous. As real numbers, we have

1/10 = 0.0001100110011001100... (base 2)

and

1/5 = 0.0011001100110011001... (base 2)

If we truncated these to, say, seven bits, then we'd get

0.0001100 + 0.0011001 = 0.0100101

while on the other hand,

3/10 = 0.01001100110011... (base 2)

which, truncated to seven bits, is 0.0100110, and these differ by exactly 0.0000001.


The exact situation is slightly more subtle because these numbers are typically stored in scientific notation. So, for instance, instead of storing 1/10 as 0.0001100 we may store it as something like 1.10011 * 2^-4, depending on how many bits we've allocated for the exponent and the mantissa. This affects how many digits of precision you get for your calculations.

The upshot is that because of these rounding errors you essentially never want to use == on floating-point numbers. Instead, you can check if the absolute value of their difference is smaller than some fixed small number.

Smart way to truncate long strings

I recently had to do this and ended up with:

/**
 * Truncate a string over a given length and add ellipsis if necessary
 * @param {string} str - string to be truncated
 * @param {integer} limit - max length of the string before truncating
 * @return {string} truncated string
 */
function truncate(str, limit) {
    return (str.length < limit) ? str : str.substring(0, limit).replace(/\w{3}$/gi, '...');
}

Feels nice and clean to me :)

How can I draw vertical text with CSS cross-browser?

If you use Bootstrap 3, you can use one of it's mixins:

.rotate(degrees);

Example:

.rotate(-90deg);

How to read embedded resource text file

I know it is an old thread, but this is what worked for me :

  1. add the text file to the project resources
  2. set the access modifier to public, as showed above by Andrew Hill
  3. read the text like this :

    textBox1 = new TextBox();
    textBox1.Text = Properties.Resources.SomeText;
    

The text that I added to the resources: 'SomeText.txt'

Tab Escape Character?

For someone who needs quick reference of C# Escape Sequences that can be used in string literals:

\t     Horizontal tab (ASCII code value: 9)

\n     Line feed (ASCII code value: 10)

\r     Carriage return (ASCII code value: 13)

\'     Single quotation mark

\"     Double quotation mark

\\     Backslash

\?     Literal question mark

\x12     ASCII character in hexadecimal notation (e.g. for 0x12)

\x1234     Unicode character in hexadecimal notation (e.g. for 0x1234)

It's worth mentioning that these (in most cases) are universal codes. So \t is 9 and \n is 10 char value on Windows and Linux. But newline sequence is not universal. On Windows it's \n\r and on Linux it's just \n. That's why it's best to use Environment.Newline which gets adjusted to current OS settings. With .Net Core it gets really important.

Search for exact match of string in excel row using VBA Macro

Never mind, I found the answer.

This will do the trick.

Dim colIndex As Long    
colIndex = Application.Match(colName, Range(Cells(rowIndex, 1), Cells(rowIndex, 100)), 0)

Browser can't access/find relative resources like CSS, images and links when calling a Servlet which forwards to a JSP

Below code worked for me.

instead of use <%@ include file="styles/default.css"%>

Difference and uses of onCreate(), onCreateView() and onActivityCreated() in fragments

onActivityCreated() - Deprecated

onActivityCreated() is now deprecated as Fragments Version 1.3.0-alpha02

The onActivityCreated() method is now deprecated. Code touching the fragment's view should be done in onViewCreated() (which is called immediately before onActivityCreated()) and other initialization code should be in onCreate(). To receive a callback specifically when the activity's onCreate() is complete, a LifeCycleObserver should be registered on the activity's Lifecycle in onAttach(), and removed once the onCreate() callback is received.

Detailed information can be found here

How to get default gateway in Mac OSX

For getting the list of ip addresses associated, you can use netstat command

netstat -rn 

This gives a long list of ip addresses and it is not easy to find the required field. The sample result is as following:

Routing tables
Internet:
Destination        Gateway            Flags        Refs      Use   Netif Expire
default            192.168.195.1      UGSc           17        0     en2
127                127.0.0.1          UCS             0        0     lo0
127.0.0.1          127.0.0.1          UH              1   254107     lo0
169.254            link#7             UCS             0        0     en2
192.168.195        link#7             UCS             3        0     en2
192.168.195.1      0:27:22:67:35:ee   UHLWIi         22      397     en2   1193
192.168.195.5      127.0.0.1          UHS             0        0     lo0

More result is truncated.......

The ip address of gateway is in the first line; one with default at its first column.

To display only the selected lines of result, we can use grep command along with netstat

netstat -rn | grep 'default'

This command filters and displays those lines of result having default. In this case, you can see result like following:

default            192.168.195.1      UGSc           14        0     en2

If you are interested in finding only the ip address of gateway and nothing else you can further filter the result using awk. The awk command matches pattern in the input result and displays the output. This can be useful when you are using your result directly in some program or batch job.

netstat -rn | grep 'default' | awk '{print $2}'

The awk command tells to match and print the second column of the result in the text. The final result thus looks like this:

192.168.195.1

In this case, netstat displays all result, grep only selects the line with 'default' in it, and awk further matches the pattern to display the second column in the text.

You can similarly use route -n get default command to get the required result. The full command is

route -n get default | grep 'gateway' | awk '{print $2}'

These commands work well in linux as well as unix systems and MAC OS.

Set width of a "Position: fixed" div relative to parent div

Fixed positioning is supposed to define everything in relation to the viewport, so position:fixed is always going to do that. Try using position:relative on the child div instead. (I realize you might need the fixed positioning for other reasons, but if so - you can't really make the width match it's parent with out JS without inherit)

Find the min/max element of an array in JavaScript

I had the same problem, I needed to obtain the minimum and maximum values of an array and, to my surprise, there were no built-in functions for arrays. After reading a lot, I decided to test the "top 3" solutions myself:

  1. discrete solution: a FOR loop to check every element of the array against the current max and/or min value;
  2. APPLY solution: sending the array to the Math.max and/or Math.min internal functions using apply(null,array);
  3. REDUCE solution: recursing a check against every element of the array using reduce(function).

The test code was this:

function GetMaxDISCRETE(A)
{   var MaxX=A[0];

    for (var X=0;X<A.length;X++)
        if (MaxX<A[X])
            MaxX=A[X];

    return MaxX;
}

function GetMaxAPPLY(A)
{   return Math.max.apply(null,A);
}

function GetMaxREDUCE(A)
{   return A.reduce(function(p,c)
    {   return p>c?p:c;
    });
}

The array A was filled with 100,000 random integer numbers, each function was executed 10,000 times on Mozilla Firefox 28.0 on an intel Pentium 4 2.99GHz desktop with Windows Vista. The times are in seconds, retrieved by performance.now() function. The results were these, with 3 fractional digits and standard deviation:

  1. Discrete solution: mean=0.161s, sd=0.078
  2. APPLY solution: mean=3.571s, sd=0.487
  3. REDUCE solution: mean=0.350s, sd=0.044

The REDUCE solution was 117% slower than the discrete solution. The APPLY solution was the worse, 2,118% slower than the discrete solution. Besides, as Peter observed, it doesn't work for large arrays (about more than 1,000,000 elements).

Also, to complete the tests, I tested this extended discrete code:

var MaxX=A[0],MinX=A[0];

for (var X=0;X<A.length;X++)
{   if (MaxX<A[X])
        MaxX=A[X];
    if (MinX>A[X])
        MinX=A[X];
}

The timing: mean=0.218s, sd=0.094

So, it is 35% slower than the simple discrete solution, but it retrieves both the maximum and the minimum values at once (any other solution would take at least twice that to retrieve them). Once the OP needed both values, the discrete solution would be the best choice (even as two separate functions, one for calculating maximum and another for calculating minimum, they would outperform the second best, the REDUCE solution).

MongoDB: Combine data from multiple collections into one..how?

use multiple $lookup for multiple collections in aggregation

query:

db.getCollection('servicelocations').aggregate([
  {
    $match: {
      serviceLocationId: {
        $in: ["36728"]
      }
    }
  },
  {
    $lookup: {
      from: "orders",
      localField: "serviceLocationId",
      foreignField: "serviceLocationId",
      as: "orders"
    }
  },
  {
    $lookup: {
      from: "timewindowtypes",
      localField: "timeWindow.timeWindowTypeId",
      foreignField: "timeWindowTypeId",
      as: "timeWindow"
    }
  },
  {
    $lookup: {
      from: "servicetimetypes",
      localField: "serviceTimeTypeId",
      foreignField: "serviceTimeTypeId",
      as: "serviceTime"
    }
  },
  {
    $unwind: "$orders"
  },
  {
    $unwind: "$serviceTime"
  },
  {
    $limit: 14
  }
])

result:

{
    "_id" : ObjectId("59c3ac4bb7799c90ebb3279b"),
    "serviceLocationId" : "36728",
    "regionId" : 1.0,
    "zoneId" : "DXBZONE1",
    "description" : "AL HALLAB REST EMIRATES MALL",
    "locationPriority" : 1.0,
    "accountTypeId" : 1.0,
    "locationType" : "SERVICELOCATION",
    "location" : {
        "makani" : "",
        "lat" : 25.119035,
        "lng" : 55.198694
    },
    "deliveryDays" : "MTWRFSU",
    "timeWindow" : [ 
        {
            "_id" : ObjectId("59c3b0a3b7799c90ebb32cde"),
            "timeWindowTypeId" : "1",
            "Description" : "MORNING",
            "timeWindow" : {
                "openTime" : "06:00",
                "closeTime" : "08:00"
            },
            "accountId" : 1.0
        }, 
        {
            "_id" : ObjectId("59c3b0a3b7799c90ebb32cdf"),
            "timeWindowTypeId" : "1",
            "Description" : "MORNING",
            "timeWindow" : {
                "openTime" : "09:00",
                "closeTime" : "10:00"
            },
            "accountId" : 1.0
        }, 
        {
            "_id" : ObjectId("59c3b0a3b7799c90ebb32ce0"),
            "timeWindowTypeId" : "1",
            "Description" : "MORNING",
            "timeWindow" : {
                "openTime" : "10:30",
                "closeTime" : "11:30"
            },
            "accountId" : 1.0
        }
    ],
    "address1" : "",
    "address2" : "",
    "phone" : "",
    "city" : "",
    "county" : "",
    "state" : "",
    "country" : "",
    "zipcode" : "",
    "imageUrl" : "",
    "contact" : {
        "name" : "",
        "email" : ""
    },
    "status" : "ACTIVE",
    "createdBy" : "",
    "updatedBy" : "",
    "updateDate" : "",
    "accountId" : 1.0,
    "serviceTimeTypeId" : "1",
    "orders" : [ 
        {
            "_id" : ObjectId("59c3b291f251c77f15790f92"),
            "orderId" : "AQ18O1704264",
            "serviceLocationId" : "36728",
            "orderNo" : "AQ18O1704264",
            "orderDate" : "18-Sep-17",
            "description" : "AQ18O1704264",
            "serviceType" : "Delivery",
            "orderSource" : "Import",
            "takenBy" : "KARIM",
            "plannedDeliveryDate" : ISODate("2017-08-26T00:00:00.000Z"),
            "plannedDeliveryTime" : "",
            "actualDeliveryDate" : "",
            "actualDeliveryTime" : "",
            "deliveredBy" : "",
            "size1" : 296.0,
            "size2" : 3573.355,
            "size3" : 240.811,
            "jobPriority" : 1.0,
            "cancelReason" : "",
            "cancelDate" : "",
            "cancelBy" : "",
            "reasonCode" : "",
            "reasonText" : "",
            "status" : "",
            "lineItems" : [ 
                {
                    "ItemId" : "BNWB020",
                    "size1" : 15.0,
                    "size2" : 78.6,
                    "size3" : 6.0
                }, 
                {
                    "ItemId" : "BNWB021",
                    "size1" : 20.0,
                    "size2" : 252.0,
                    "size3" : 11.538
                }, 
                {
                    "ItemId" : "BNWB023",
                    "size1" : 15.0,
                    "size2" : 285.0,
                    "size3" : 16.071
                }, 
                {
                    "ItemId" : "CPMW112",
                    "size1" : 3.0,
                    "size2" : 25.38,
                    "size3" : 1.731
                }, 
                {
                    "ItemId" : "MMGW001",
                    "size1" : 25.0,
                    "size2" : 464.375,
                    "size3" : 46.875
                }, 
                {
                    "ItemId" : "MMNB218",
                    "size1" : 50.0,
                    "size2" : 920.0,
                    "size3" : 60.0
                }, 
                {
                    "ItemId" : "MMNB219",
                    "size1" : 50.0,
                    "size2" : 630.0,
                    "size3" : 40.0
                }, 
                {
                    "ItemId" : "MMNB220",
                    "size1" : 50.0,
                    "size2" : 416.0,
                    "size3" : 28.846
                }, 
                {
                    "ItemId" : "MMNB270",
                    "size1" : 50.0,
                    "size2" : 262.0,
                    "size3" : 20.0
                }, 
                {
                    "ItemId" : "MMNB302",
                    "size1" : 15.0,
                    "size2" : 195.0,
                    "size3" : 6.0
                }, 
                {
                    "ItemId" : "MMNB373",
                    "size1" : 3.0,
                    "size2" : 45.0,
                    "size3" : 3.75
                }
            ],
            "accountId" : 1.0
        }, 
        {
            "_id" : ObjectId("59c3b291f251c77f15790f9d"),
            "orderId" : "AQ137O1701240",
            "serviceLocationId" : "36728",
            "orderNo" : "AQ137O1701240",
            "orderDate" : "18-Sep-17",
            "description" : "AQ137O1701240",
            "serviceType" : "Delivery",
            "orderSource" : "Import",
            "takenBy" : "KARIM",
            "plannedDeliveryDate" : ISODate("2017-08-26T00:00:00.000Z"),
            "plannedDeliveryTime" : "",
            "actualDeliveryDate" : "",
            "actualDeliveryTime" : "",
            "deliveredBy" : "",
            "size1" : 28.0,
            "size2" : 520.11,
            "size3" : 52.5,
            "jobPriority" : 1.0,
            "cancelReason" : "",
            "cancelDate" : "",
            "cancelBy" : "",
            "reasonCode" : "",
            "reasonText" : "",
            "status" : "",
            "lineItems" : [ 
                {
                    "ItemId" : "MMGW001",
                    "size1" : 25.0,
                    "size2" : 464.38,
                    "size3" : 46.875
                }, 
                {
                    "ItemId" : "MMGW001-F1",
                    "size1" : 3.0,
                    "size2" : 55.73,
                    "size3" : 5.625
                }
            ],
            "accountId" : 1.0
        }, 
        {
            "_id" : ObjectId("59c3b291f251c77f15790fd8"),
            "orderId" : "AQ110O1705036",
            "serviceLocationId" : "36728",
            "orderNo" : "AQ110O1705036",
            "orderDate" : "18-Sep-17",
            "description" : "AQ110O1705036",
            "serviceType" : "Delivery",
            "orderSource" : "Import",
            "takenBy" : "KARIM",
            "plannedDeliveryDate" : ISODate("2017-08-26T00:00:00.000Z"),
            "plannedDeliveryTime" : "",
            "actualDeliveryDate" : "",
            "actualDeliveryTime" : "",
            "deliveredBy" : "",
            "size1" : 60.0,
            "size2" : 1046.0,
            "size3" : 68.0,
            "jobPriority" : 1.0,
            "cancelReason" : "",
            "cancelDate" : "",
            "cancelBy" : "",
            "reasonCode" : "",
            "reasonText" : "",
            "status" : "",
            "lineItems" : [ 
                {
                    "ItemId" : "MMNB218",
                    "size1" : 50.0,
                    "size2" : 920.0,
                    "size3" : 60.0
                }, 
                {
                    "ItemId" : "MMNB219",
                    "size1" : 10.0,
                    "size2" : 126.0,
                    "size3" : 8.0
                }
            ],
            "accountId" : 1.0
        }
    ],
    "serviceTime" : {
        "_id" : ObjectId("59c3b07cb7799c90ebb32cdc"),
        "serviceTimeTypeId" : "1",
        "serviceTimeType" : "nohelper",
        "description" : "",
        "fixedTime" : 30.0,
        "variableTime" : 0.0,
        "accountId" : 1.0
    }
}

REST API - file (ie images) processing - best practices

There are several decisions to make:

  1. The first about resource path:

    • Model the image as a resource on its own:

      • Nested in user (/user/:id/image): the relationship between the user and the image is made implicitly

      • In the root path (/image):

        • The client is held responsible for establishing the relationship between the image and the user, or;

        • If a security context is being provided with the POST request used to create an image, the server can implicitly establish a relationship between the authenticated user and the image.

    • Embed the image as part of the user

  2. The second decision is about how to represent the image resource:

    • As Base 64 encoded JSON payload
    • As a multipart payload

This would be my decision track:

  • I usually favor design over performance unless there is a strong case for it. It makes the system more maintainable and can be more easily understood by integrators.
  • So my first thought is to go for a Base64 representation of the image resource because it lets you keep everything JSON. If you chose this option you can model the resource path as you like.
    • If the relationship between user and image is 1 to 1 I'd favor to model the image as an attribute specially if both data sets are updated at the same time. In any other case you can freely choose to model the image either as an attribute, updating the it via PUT or PATCH, or as a separate resource.
  • If you choose multipart payload I'd feel compelled to model the image as a resource on is own, so that other resources, in our case, the user resource, is not impacted by the decision of using a binary representation for the image.

Then comes the question: Is there any performance impact about choosing base64 vs multipart?. We could think that exchanging data in multipart format should be more efficient. But this article shows how little do both representations differ in terms of size.

My choice Base64:

  • Consistent design decision
  • Negligible performance impact
  • As browsers understand data URIs (base64 encoded images), there is no need to transform these if the client is a browser
  • I won't cast a vote on whether to have it as an attribute or standalone resource, it depends on your problem domain (which I don't know) and your personal preference.

Carriage return in C?

From 5.2.2/2 (character display semantics) :

\b (backspace) Moves the active position to the previous position on the current line. If the active position is at the initial position of a line, the behavior of the display device is unspecified.

\n (new line) Moves the active position to the initial position of the next line.

\r (carriage return) Moves the active position to the initial position of the current line.

Here, your code produces :

  • <new_line>ab
  • \b : back one character
  • write si : overrides the b with s (producing asi on the second line)
  • \r : back at the beginning of the current line
  • write ha : overrides the first two characters (producing hai on the second line)

In the end, the output is :

\nhai

How can I limit the visible options in an HTML <select> dropdown?

It is not possible to limit the number of visible elements in the select dropdown (if you use it as dropdown box and not as list).

But you could use javascript/jQuery to replace this selectbox with something else, which just looks like a dropdown box. Then you can handle the height of dropdown as you want.

jNice would be a jQuery plugin which has such features. But there also exists many alternatives for that.

NULL vs nullptr (Why was it replaced?)

You can find a good explanation of why it was replaced by reading A name for the null pointer: nullptr, to quote the paper:

This problem falls into the following categories:

  • Improve support for library building, by providing a way for users to write less ambiguous code, so that over time library writers will not need to worry about overloading on integral and pointer types.

  • Improve support for generic programming, by making it easier to express both integer 0 and nullptr unambiguously.

  • Make C++ easier to teach and learn.

Serialize Class containing Dictionary member

Dictionaries and Hashtables are not serializable with XmlSerializer. Therefore you cannot use them directly. A workaround would be to use the XmlIgnore attribute to hide those properties from the serializer and expose them via a list of serializable key-value pairs.

PS: constructing an XmlSerializer is very expensive, so always cache it if there is a chance of being able to re-use it.

PL/pgSQL checking if a row exists

Use count(*)

declare 
   cnt integer;
begin
  SELECT count(*) INTO cnt
  FROM people
  WHERE person_id = my_person_id;

IF cnt > 0 THEN
  -- Do something
END IF;

Edit (for the downvoter who didn't read the statement and others who might be doing something similar)

The solution is only effective because there is a where clause on a column (and the name of the column suggests that its the primary key - so the where clause is highly effective)

Because of that where clause there is no need to use a LIMIT or something else to test the presence of a row that is identified by its primary key. It is an effective way to test this.

How to change btn color in Bootstrap

Remove the button color class like "btn-success" and put a custom class like "btn-custom" and write css for that class. That simply works for me.

HTML :

<button class="btn btn-block login " type="submit">Sign In</button>

CSS:

 .login  {
    background-color: #0057fc;
    color: white;   
}

Replace first occurrence of string in Python

string replace() function perfectly solves this problem:

string.replace(s, old, new[, maxreplace])

Return a copy of string s with all occurrences of substring old replaced by new. If the optional argument maxreplace is given, the first maxreplace occurrences are replaced.

>>> u'longlongTESTstringTEST'.replace('TEST', '?', 1)
u'longlong?stringTEST'

Allowed memory size of 262144 bytes exhausted (tried to allocate 24576 bytes)

The value of 262,144 bytes is the key to the diagnosis. You'll see this magic number pop up in PHP questions all over the place. Why? Because that is the value PHP will end up with as its memory limit if you attempt to update the limit with a value it can't use. An empty string will produce this memory limit, as will an incorrect unit notation like '128MB' instead of the correct '128M'.

262,144 bytes is exactly 256 Kibibytes. Why PHP runs home to that value when it gets confused is beyond me.

isn't it weird that allowed memory is bigger than allocated memory?

The allocated amount shown is just the most recent allocation attempt, the one that ran afoul of the memory limit. See Allowed memory size in PHP when allocating less.

How to change color of Android ListView separator line?

For a single color line use:

list.setDivider(new ColorDrawable(0x99F10529));   //0xAARRGGBB
list.setDividerHeight(1);

It's important that DividerHeight is set after the divider, else you won't get anything.

What is SYSNAME data type in SQL Server?

Another use case is when using the SQL Server 2016+ functionality of AT TIME ZONE

The below statement will return a date converted to GMT

SELECT 
CONVERT(DATETIME, SWITCHOFFSET([ColumnA], DATEPART(TZOFFSET, [ColumnA] AT TIME ZONE 'GMT Standard Time')))

If you want to pass the time zone as a variable, say:

SELECT 
CONVERT(DATETIME, SWITCHOFFSET([ColumnA], DATEPART(TZOFFSET, [ColumnA] AT TIME ZONE @TimeZone)))

then that variable needs to be of the type sysname (declaring it as varchar will cause an error).

How can I remove or replace SVG content?

I had two charts.

<div id="barChart"></div>
<div id="bubbleChart"></div>

This removed all charts.

d3.select("svg").remove(); 

This worked for removing the existing bar chart, but then I couldn't re-add the bar chart after

d3.select("#barChart").remove();

Tried this. It not only let me remove the existing bar chart, but also let me re-add a new bar chart.

d3.select("#barChart").select("svg").remove();

var svg = d3.select('#barChart')
       .append('svg')
       .attr('width', width + margins.left + margins.right)
       .attr('height', height + margins.top + margins.bottom)
       .append('g')
       .attr('transform', 'translate(' + margins.left + ',' + margins.top + ')');

Not sure if this is the correct way to remove, and re-add a chart in d3. It worked in Chrome, but have not tested in IE.

Parsing time string in Python

It has discussed many times in SO. In short, "%z" is not supported because platform not support it. My solution is a new one, just skip the time zone.:

    datetime.datetime.strptime(re.sub(r"[+-]([0-9])+", "", "Tue May 08 15:14:45 +0800 2012"),"%a %b %d %H:%M:%S %Y")

CSS selector for text input fields?

input[type=text]

This will select all the input type text in a web-page.

Multiple github accounts on the same computer?

Unlike other answers, where you need to follow few steps to use two different github account from same machine, for me it worked in two steps.

You just need to :

1) generate SSH public and private key pair for each of your account under ~/.ssh location with different names and

2) add the generated public keys to the respective account under Settings >> SSH and GPG keys >> New SSH Key.

To generate the SSH public and private key pairs use following command:

cd ~/.ssh
ssh-keygen -t rsa -C "[email protected]" -f "id_rsa_WORK"
ssh-keygen -t rsa -C "[email protected]" -f "id_rsa_PERSONAL"

As a result of above commands, id_rsa_WORK and id_rsa_WORK.pub files will be created for your work account (ex - git.work.com) and id_rsa_PERSONAL and id_rsa_PERSONAL.pub will be created for your personal account (ex - github.com).

Once created, copy the content from each public (*.pub) file and do Step 2 for the each account.

PS : Its not necessary to make an host entry for each git account under ~/.ssh/config file as mentioned in other answers, if hostname of your two accounts are different.

JavaScript get child element

Try this one:

function show_sub(cat) {
    var parent = cat,
    sub = parent.getElementsByClassName('sub');
    if (sub[0].style.display == 'inline'){
        sub[0].style.display = 'none';
    }
    else {
        sub[0].style.display = 'inline';
    }
}

document.getElementById('cat').onclick = function(){
    show_sub(this);
};?

and use this for IE6 & 7

if (typeof document.getElementsByClassName!='function') {
    document.getElementsByClassName = function() {
        var elms = document.getElementsByTagName('*');
        var ei = new Array();
        for (i=0;i<elms.length;i++) {
            if (elms[i].getAttribute('class')) {
               ecl = elms[i].getAttribute('class').split(' ');
                for (j=0;j<ecl.length;j++) {
                    if (ecl[j].toLowerCase() == arguments[0].toLowerCase()) {
                        ei.push(elms[i]);
                    }
                }
            } else if (elms[i].className) {
                ecl = elms[i].className.split(' ');
                for (j=0;j<ecl.length;j++) {
                    if (ecl[j].toLowerCase() == arguments[0].toLowerCase()) {
                        ei.push(elms[i]);
                    }
                }
            }
        }
        return ei;
    }
}

How to insert double and float values to sqlite?

actually I think your code is just fine.. you can save those values as strings (TEXT) just like you did.. (if you want to)

and you probably get the error for the System.currentTimeMillis() that might be too big for INTEGER

Create folder with batch but only if it doesn't already exist

This should work for you:

IF NOT EXIST "\path\to\your\folder" md \path\to\your\folder

However, there is another method, but it may not be 100% useful:

md \path\to\your\folder >NUL 2>NUL

This one creates the folder, but does not show the error output if folder exists. I highly recommend that you use the first one. The second one is if you have problems with the other.

Is there an equivalent to background-size: cover and contain for image elements?

background:url('/image/url/') right top scroll; 
background-size: auto 100%; 
min-height:100%;

encountered same exact symptops. above worked for me.

Better way to right align text in HTML Table

You could use the nth-child pseudo-selector. For example:

table.align-right-3rd-column td:nth-child(3)
{
  text-align: right;
}

Then in your table do:

<table class="align-right-3rd-column">
  <tr>
    <td></td><td></td><td></td>
    ...
  </tr>
</table>

Edit:

Unfortunately, this only works in Firefox 3.5. However, if your table only has 3 columns, you could use the sibling selector, which has much better browser support. Here's what the style sheet would look like:

table.align-right-3rd-column td + td + td
{
  text-align: right;
}

This will match any column preceded by two other columns.

Play/pause HTML 5 video using JQuery

    enter code here
<form class="md-form" action="#">
  <div class="file-field">
    <div class="btn btn-primary btn-sm float-left">
      <span>Choose files</span>
      <input type="file" multiple>
    </div>
    <div class="file-path-wrapper">
      <input class="file-path validate" type="text" placeholder="Upload one or more files">
    </div>
  </div>
</form>

<video  width="320" height="240" id="keerthan"></video>

<button onclick="playVid()" type="button">Play Video</button>
<button onclick="pauseVid()" type="button">Pause Video</button> 
<script>
    (function localFileVideoPlayer() {

  var playSelectedFile = function (event) {
    var file = this.files[0]
    var type = file.type
    var videoNode = document.querySelector('video')




    var fileURL = URL.createObjectURL(file)
    videoNode.src = fileURL
  }
  var inputNode = document.querySelector('input')
  inputNode.addEventListener('change', playSelectedFile, false)
})()
function playVid() { 
  keerthan.play(); 
} 

function pauseVid() { 
  keerthan.pause(); 
} 

</script>

How to describe table in SQL Server 2008?

You can use keyboard short-cut for Description/ detailed information of Table in SQL Server 2008.

Follow steps:

  1. Write Table Name,
  2. Select it, and press Alt + F1
  3. It will show detailed information/ description of mentioned table as,

    1) Table created date,
    2) Columns Description,
    3) Identity,
    4) Indexes,
    5) Constraints,
    6) References etc. As shown Below [example]:

Alt+F1 Demo

SQL Server Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >=

SELECT COLUMN 
    FROM TABLE 
WHERE columns_name
    IN ( SELECT COLUMN FROM TABLE WHERE columns_name = 'value');

note: when we are using sub-query we must focus on these points:

  1. if our sub query returns 1 value in this case we need to use (=,!=,<>,<,>....)
  2. else (more than one value), in this case we need to use (in, any, all, some )

How can I enable Assembly binding logging?

For me the 'Bla' file was System.Net.http dll which was missing from my BIN folder. I just added it and it worked fine. Didn't change any registry key or anything of that sort.

Returning JSON object as response in Spring Boot

The reason why your current approach doesn't work is because Jackson is used by default to serialize and to deserialize objects. However, it doesn't know how to serialize the JSONObject. If you want to create a dynamic JSON structure, you can use a Map, for example:

@GetMapping
public Map<String, String> sayHello() {
    HashMap<String, String> map = new HashMap<>();
    map.put("key", "value");
    map.put("foo", "bar");
    map.put("aa", "bb");
    return map;
}

This will lead to the following JSON response:

{ "key": "value", "foo": "bar", "aa": "bb" }

This is a bit limited, since it may become a bit more difficult to add child objects. Jackson has its own mechanism though, using ObjectNode and ArrayNode. To use it, you have to autowire ObjectMapper in your service/controller. Then you can use:

@GetMapping
public ObjectNode sayHello() {
    ObjectNode objectNode = mapper.createObjectNode();
    objectNode.put("key", "value");
    objectNode.put("foo", "bar");
    objectNode.put("number", 42);
    return objectNode;
}

This approach allows you to add child objects, arrays, and use all various types.

Using the grep and cut delimiter command (in bash shell scripting UNIX) - and kind of "reversing" it?

You don't need to change the delimiter to display the right part of the string with cut.

The -f switch of the cut command is the n-TH element separated by your delimiter : :, so you can just type :

 grep puddle2_1557936 | cut -d ":" -f2

Another solutions (adapt it a bit) if you want fun :

Using :

grep -oP 'puddle2_1557936:\K.*' <<< 'puddle2_1557936:/home/rogers.williams/folderz/puddle2'                                                                        
/home/rogers.williams/folderz/puddle2

or still with look around

grep -oP '(?<=puddle2_1557936:).*' <<< 'puddle2_1557936:/home/rogers.williams/folderz/puddle2'                                                                    
/home/rogers.williams/folderz/puddle2

or with :

perl -lne '/puddle2_1557936:(.*)/ and print $1' <<< 'puddle2_1557936:/home/rogers.williams/folderz/puddle2'                                                      
/home/rogers.williams/folderz/puddle2

or using (thanks to glenn jackman)

ruby -F: -ane '/puddle2_1557936/ and puts $F[1]' <<< 'puddle2_1557936:/home/rogers.williams/folderz/puddle2'
/home/rogers.williams/folderz/puddle2

or with :

awk -F'puddle2_1557936:' '{print $2}'  <<< 'puddle2_1557936:/home/rogers.williams/folderz/puddle2'
/home/rogers.williams/folderz/puddle2

or with :

python -c 'import sys; print(sys.argv[1].split("puddle2_1557936:")[1])' 'puddle2_1557936:/home/rogers.williams/folderz/puddle2'
/home/rogers.williams/folderz/puddle2

or using only :

IFS=: read _ a <<< "puddle2_1557936:/home/rogers.williams/folderz/puddle2"
echo "$a"
/home/rogers.williams/folderz/puddle2

or using in a :

js<<EOF
var x = 'puddle2_1557936:/home/rogers.williams/folderz/puddle2'
print(x.substr(x.indexOf(":")+1))
EOF
/home/rogers.williams/folderz/puddle2

or using in a :

php -r 'preg_match("/puddle2_1557936:(.*)/", $argv[1], $m); echo "$m[1]\n";' 'puddle2_1557936:/home/rogers.williams/folderz/puddle2' 
/home/rogers.williams/folderz/puddle2

Is there a mechanism to loop x times in ES6 (ECMAScript 6) without mutable variables?

I think the best solution is to use let:

for (let i=0; i<100; i++) …

That will create a new (mutable) i variable for each body evaluation and assures that the i is only changed in the increment expression in that loop syntax, not from anywhere else.

I could kind of cheat and make my own generator. At least i++ is out of sight :)

That should be enough, imo. Even in pure languages, all operations (or at least, their interpreters) are built from primitives that use mutation. As long as it is properly scoped, I cannot see what is wrong with that.

You should be fine with

function* times(n) {
  for (let i = 0; i < n; i++)
    yield i;
}
for (const i of times(5)) {
  console.log(i);
}

But I don't want to use the ++ operator or have any mutable variables at all.

Then your only choice is to use recursion. You can define that generator function without a mutable i as well:

function* range(i, n) {
  if (i >= n) return;
  yield i;
  return yield* range(i+1, n);
}
times = (n) => range(0, n);

But that seems overkill to me and might have performance problems (as tail call elimination is not available for return yield*).

Removing multiple files from a Git repo that have already been deleted from disk

Adding system alias for staging deleted files as command rm-all

UNIX alias rm-all='git rm $(git ls-files --deleted)'

WINDOWS doskey rm-all=bash -c "git rm $(git ls-files --deleted)"

Note

Windows needs to have bash installed.

Codeigniter's `where` and `or_where`

$this->db->where('(a = 1 or a = 2)');

JAVA_HOME is set to an invalid directory:

You should set it with C:\Program Files\Java\jdk1.8.0_12.

\bin is not required.

How to remove extension from string (only real extension!)

Try to use this one. it will surely remove the file extension.

$filename = "image.jpg";
$e = explode(".", $filename);
foreach($e as $key=>$d)
{
if($d!=end($e)
{

$new_d[]=$d; 
}

 }
 echo implode("-",$new_t);  // result would be just the 'image'

Java default constructor

A default constructor does not take any arguments:

public class Student { 
    // default constructor
    public Student() {   

    }
}

Prevent Caching in ASP.NET MVC for specific actions using an attribute

Here's the NoCache attribute proposed by mattytommo, simplified by using the information from Chris Moschini's answer:

[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
public sealed class NoCacheAttribute : OutputCacheAttribute
{
    public NoCacheAttribute()
    {
        this.Duration = 0;
    }
}

Could not load file or assembly '***.dll' or one of its dependencies

or one of its dependencies

That's the usual problem, you cannot see a missing unmanaged DLL with Fuslogvw.exe. Best thing to do is to run SysInternals' ProcMon utility. You'll see it searching for the DLL and not find it. Profile mode in Dependency Walker can show it too.

Query to get only numbers from a string

First create this UDF

CREATE FUNCTION dbo.udf_GetNumeric
(
  @strAlphaNumeric VARCHAR(256)
)
RETURNS VARCHAR(256)
AS
BEGIN
  DECLARE @intAlpha INT
  SET @intAlpha = PATINDEX('%[^0-9]%', @strAlphaNumeric)
  BEGIN
    WHILE @intAlpha > 0
    BEGIN
      SET @strAlphaNumeric = STUFF(@strAlphaNumeric, @intAlpha, 1, '' )
      SET @intAlpha = PATINDEX('%[^0-9]%', @strAlphaNumeric )
    END
  END
  RETURN ISNULL(@strAlphaNumeric,0)
END
GO

Now use the function as

SELECT dbo.udf_GetNumeric(column_name) 
from table_name

SQL FIDDLE

I hope this solved your problem.

Reference

Double vs. BigDecimal?

My English is not good so I'll just write a simple example here.

    double a = 0.02;
    double b = 0.03;
    double c = b - a;
    System.out.println(c);

    BigDecimal _a = new BigDecimal("0.02");
    BigDecimal _b = new BigDecimal("0.03");
    BigDecimal _c = _b.subtract(_a);
    System.out.println(_c);

Program output:

0.009999999999999998
0.01

Somebody still want to use double? ;)

char initial value in Java

i would just do:

char x = 0; //Which will give you an empty value of character

What are the rules for calling the superclass constructor?

Nobody mentioned the sequence of constructor calls when a class derives from multiple classes. The sequence is as mentioned while deriving the classes.

How to stop EditText from gaining focus at Activity startup in Android

Try this before your first editable field:

<TextView  
        android:id="@+id/dummyfocus" 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" 
        android:text="@string/foo"
        />

----

findViewById(R.id.dummyfocus).setFocusableInTouchMode(true);
findViewById(R.id.dummyfocus).requestFocus();

animating addClass/removeClass with jQuery

Since you are not worried about IE, why not just use css transitions to provide the animation and jQuery to change the classes. Live example: http://jsfiddle.net/tw16/JfK6N/

#someDiv{
    -webkit-transition: all 0.5s ease;
    -moz-transition: all 0.5s ease;
    -o-transition: all 0.5s ease;
    transition: all 0.5s ease;
}

Java: export to an .jar file in eclipse

Go to file->export->JAR file, there you may select "Export generated class files and sources" and make sure that your project is selected, and all folder under there are also! Good luck!

Java Could not reserve enough space for object heap error

this is what worked for me (yes I was having the same problem) were is says something like java -Xmx3G -Xms3G put java -Xmx1024M so the run.bat should look like java -Xmx1024M -jar craftbukkit.jar -o false PAUSE

PostgreSQL database service

If you don't want or can't install postgres again, you can install the server from the binary zip like this post explains it.

java.lang.NoSuchMethodError: javax.servlet.ServletContext.getContextPath()Ljava/lang/String;

java.lang.NoSuchMethodError: javax.servlet.ServletContext.getContextPath()Ljava/lang/String;

That method was added in Servlet 2.5.

So this problem can have at least 3 causes:

  1. The servlet container does not support Servlet 2.5.
  2. The web.xml is not declared conform Servlet 2.5 or newer.
  3. The webapp's runtime classpath is littered with servlet container specific JAR files of a different servlet container make/version which does not support Servlet 2.5.

To solve it,

  1. Make sure that your servlet container supports at least Servlet 2.5. That are at least Tomcat 6, Glassfish 2, JBoss AS 4.1, etcetera. Tomcat 5.5 for example supports at highest Servlet 2.4. If you can't upgrade Tomcat, then you'd need to downgrade Spring to a Servlet 2.4 compatible version.
  2. Make sure that the root declaration of web.xml complies Servlet 2.5 (or newer, at least the highest whatever your target runtime supports). For an example, see also somewhere halfway our servlets wiki page.
  3. Make sure that you don't have any servlet container specific libraries like servlet-api.jar or j2ee.jar in /WEB-INF/lib or even worse, the JRE/lib or JRE/lib/ext. They do not belong there. This is a pretty common beginner's mistake in an attempt to circumvent compilation errors in an IDE, see also How do I import the javax.servlet API in my Eclipse project?.

get the value of input type file , and alert if empty

<script type="text/javascript">
$(document).ready(function() {
    $('#upload').bind("click",function() 
    { 
        var imgVal = $('#uploadImage').val(); 
        if(imgVal=='') 
        { 
            alert("empty input file"); 

        } 
        return false; 

    }); 
});
</script> 

<input type="file" name="image" id="uploadImage" size="30" /> 
<input type="submit" name="upload" id="upload"  class="send_upload" value="upload" /> 

What is the difference between JSF, Servlet and JSP?

JSF is an advanced framework wherein its very easy to implement Model-View-Controller (MVC) based architecture for projects. Main advantage of JSF over JSP is the easy dynamic rendering of the components on the browser based upon conditions and easy integration of ajax events.

The front end of the JSF application i.e. xhtml files are the ones which are shown to the user via browser. These xhtml files internally invoke managed beans e.g. controllers wherein actual application logic is written.

The controllers internally invoke various services which communicate with database (using Hibernate or JPA API). This is how the flow happens in short.

JSF is also used in combination with RichFaces which is a framework for giving rich look and feel to your web application.

JSF + RichFaces + Hibernate/JPA is a good technology to learn for sure !

How do I check for null values in JavaScript?

Checking error conditions:

// Typical API response data
let data = {
  status: true,
  user: [],
  total: 0,
  activity: {sports: 1}
}

// A flag that checks whether all conditions were met or not
var passed = true;

// Boolean check
if (data['status'] === undefined || data['status'] == false){
  console.log("Undefined / no `status` data");
  passed = false;
}

// Array/dict check
if (data['user'] === undefined || !data['user'].length){
  console.log("Undefined / no `user` data");
  passed = false;
}

// Checking a key in a dictionary
if (data['activity'] === undefined || data['activity']['time'] === undefined){
   console.log("Undefined / no `time` data");
   passed = false;
}

// Other values check
if (data['total'] === undefined || !data['total']){
  console.log("Undefined / no `total` data");
  passed = false;
}

// Passed all tests?
if (passed){
  console.log("Passed all tests");
}

How to use bitmask?

Let's say I have 32-bit ARGB value with 8-bits per channel. I want to replace the alpha component with another alpha value, such as 0x45

unsigned long alpha = 0x45
unsigned long pixel = 0x12345678;
pixel = ((pixel & 0x00FFFFFF) | (alpha << 24));

The mask turns the top 8 bits to 0, where the old alpha value was. The alpha value is shifted up to the final bit positions it will take, then it is OR-ed into the masked pixel value. The final result is 0x45345678 which is stored into pixel.

How to add url parameter to the current url?

function currentUrl() {
    $protocol = strpos(strtolower($_SERVER['SERVER_PROTOCOL']),'https') === FALSE ? 'http' : 'https';
    $host     = $_SERVER['HTTP_HOST'];
    $script   = $_SERVER['SCRIPT_NAME'];
    $params   = $_SERVER['QUERY_STRING'];

    return $protocol . '://' . $host . $script . '?' . $params;
}

Then add your value with something like;

echo currentUrl().'&value=myVal';

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

You're looking for fmod().

I guess to more specifically answer your question, in older languages the % operator was just defined as integer modular division and in newer languages they decided to expand the definition of the operator.

EDIT: If I were to wager a guess why, I would say it's because the idea of modular arithmetic originates in number theory and deals specifically with integers.

How to remove trailing whitespace in code, using another script?

You don't see any output from the print statements because FileInput redirects stdout to the input file when the keyword argument inplace=1 is given. This causes the input file to effectively be rewritten and if you look at it afterwards the lines in it will indeed have no trailing or leading whitespace in them (except for the newline at the end of each which the print statement adds back).

If you only want to remove trailing whitespace, you should use rstrip() instead of strip(). Also note that the if lines == '': continue is causing blank lines to be completely removed (regardless of whether strip or rstrip gets used).

Unless your intent is to rewrite the input file, you should probably just use for line in open(filename):. Otherwise you can see what's being written to the file by simultaneously echoing the output to sys.stderr using something like the following:

import fileinput
import sys

for line in (line.rstrip() for line in
                fileinput.FileInput("test.txt", inplace=1)):
    if line:
        print line
        print >>sys.stderr, line

How does Java deal with multiple conditions inside a single IF statement

Yes,that is called short-circuiting.

Please take a look at this wikipedia page on short-circuiting

How do I use properly CASE..WHEN in MySQL

I think part of it is that you're stating the value you're selecting after CASE, and then using WHEN x = y syntax afterward, which is a combination of two different methods of using CASE. It should either be

CASE X
  WHEN a THEN ...
  WHEN b THEN ...

or

CASE
  WHEN x = a THEN ...
  WHEN x = b THEN ...

PHPExcel - creating multiple sheets by iteration

You can write different sheets as follows

$objPHPExcel = new PHPExcel();
$objPHPExcel->getProperties()->setCreator("creater");
$objPHPExcel->getProperties()->setLastModifiedBy("Middle field");
$objPHPExcel->getProperties()->setSubject("Subject");
$objWorkSheet = $objPHPExcel->createSheet();
$work_sheet_count=3;//number of sheets you want to create
$work_sheet=0;
while($work_sheet<=$work_sheet_count){ 
     if($work_sheet==0){
         $objWorkSheet->setTitle("Worksheet$work_sheet");
         $objPHPExcel->setActiveSheetIndex($work_sheet)->setCellValue('A1', 'SR No. In sheet 1')->getStyle('A1')->getFont()->setBold(true);
         $objPHPExcel->setActiveSheetIndex($work_sheet)->setCellValueByColumnAndRow($col++, $row++, $i++);//setting value by column and row indexes if needed
     }
     if($work_sheet==1){
         $objWorkSheet->setTitle("Worksheet$work_sheet");
         $objPHPExcel->setActiveSheetIndex($work_sheet)->setCellValue('A1', 'SR No. In sheet 2')->getStyle('A1')->getFont()->setBold(true);
         $objPHPExcel->setActiveSheetIndex($work_sheet)->setCellValueByColumnAndRow($col++, $row++, $i++);//setting value by column and row indexes if needed
     }
     if($work_sheet==2){
         $objWorkSheet = $objPHPExcel->createSheet($work_sheet_count);
         $objWorkSheet->setTitle("Worksheet$work_sheet");
         $objPHPExcel->setActiveSheetIndex($work_sheet)->setCellValue('A1', 'SR No. In sheet 3')->getStyle('A1')->getFont()->setBold(true);
         $objPHPExcel->setActiveSheetIndex($work_sheet)->setCellValueByColumnAndRow($col++, $row++, $i++);//setting value by column and row indexes if needed
     }
     $work_sheet++;
}

$filename='file-name'.'.xls'; //save our workbook as this file name
header('Content-Type: application/vnd.ms-excel'); //mime type
header('Content-Disposition: attachment;filename="'.$filename.'"'); //tell browser what's the file name
header('Cache-Control: max-age=0'); //no cach

$objWriter = PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel5');
$objWriter->save('php://output');

How can I change the date format in Java?

How to convert from one date format to another using SimpleDateFormat:

final String OLD_FORMAT = "dd/MM/yyyy";
final String NEW_FORMAT = "yyyy/MM/dd";

// August 12, 2010
String oldDateString = "12/08/2010";
String newDateString;

SimpleDateFormat sdf = new SimpleDateFormat(OLD_FORMAT);
Date d = sdf.parse(oldDateString);
sdf.applyPattern(NEW_FORMAT);
newDateString = sdf.format(d);

Rails has_many with alias name

To complete @SamSaffron's answer :

You can use class_name with either foreign_key or inverse_of. I personally prefer the more abstract declarative, but it's really just a matter of taste :

class BlogPost
  has_many :images, class_name: "BlogPostImage", inverse_of: :blog_post  
end

and you need to make sure you have the belongs_to attribute on the child model:

class BlogPostImage
  belongs_to :blog_post
end

How to link an image and target a new window

you can do like this

<a href="http://www.w3c.org/" target="_blank">W3C Home Page</a>

find this page

http://www.corelangs.com/html/links/new-window.html

goreb

How to show SVG file on React Native?

Use https://github.com/kristerkari/react-native-svg-transformer

In this package it is mentioned that .svg files are not supported in React Native v0.57 and lower so use .svgx extension for svg files.

For web or react-native-web use https://www.npmjs.com/package/@svgr/webpack


To render svg files using react-native-svg-uri with react-native version 0.57 and lower, you need to add following files to your root project

Note: change extension svg to svgx

step 1: add file transformer.js to project's root

// file: transformer.js

const cleanupSvg = require('./cleanup-svg');

const upstreamTransformer = require("metro/src/transformer");

// const typescriptTransformer = require("react-native-typescript-transformer");
// const typescriptExtensions = ["ts", "tsx"];

const svgExtensions = ["svgx"]

// function cleanUpSvg(text) {
//   text = text.replace(/width="([#0-9]+)px"/gi, "");
//    text = text.replace(/height="([#0-9]+)px"/gi, "");
//    return text;
// }

function fixRenderingBugs(content) {
  // content = cleanUpSvg(content); // cleanupSvg removes width and height attributes from svg
  return "module.exports = `" + content + "`";
}


module.exports.transform = function ({ src, filename, options }) {
  // if (typescriptExtensions.some(ext => filename.endsWith("." + ext))) {
  //  return typescriptTransformer.transform({ src, filename, options })
  // }

  if (svgExtensions.some(ext => filename.endsWith("." + ext))) {
    return upstreamTransformer.transform({
      src: fixRenderingBugs(src),
      filename,
      options
    })
  }

  return upstreamTransformer.transform({ src, filename, options });
}

step 2: add rn-cli.config.js to project's root

module.exports = {
    getTransformModulePath() {
      return require.resolve("./transformer");
    },
    getSourceExts() {
      return [/* "ts", "tsx", */ "svgx"];
    }
  };

The above mentioned solutions will work in production apps too ?

Adding data attribute to DOM

jQuery's .data() does a couple things but it doesn't add the data to the DOM as an attribute. When using it to grab a data attribute, the first thing it does is create a jQuery data object and sets the object's value to the data attribute. After that, it's essentially decoupled from the data attribute.

Example:

<div data-foo="bar"></div>

If you grabbed the value of the attribute using .data('foo'), it would return "bar" as you would expect. If you then change the attribute using .attr('data-foo', 'blah') and then later use .data('foo') to grab the value, it would return "bar" even though the DOM says data-foo="blah". If you use .data() to set the value, it'll change the value in the jQuery object but not in the DOM.

Basically, .data() is for setting or checking the jQuery object's data value. If you are checking it and it doesn't already have one, it creates the value based on the data attribute that is in the DOM. .attr() is for setting or checking the DOM element's attribute value and will not touch the jQuery data value. If you need them both to change you should use both .data() and .attr(). Otherwise, stick with one or the other.

HashMap and int as key

use int as Object not as primitive type

HashMap<Integer, myObject> myMap = new HashMap<Integer, myObject>();

<Django object > is not JSON serializable

Another great way of solving it while using a model is by using the values() function.

def returnResponse(date):
    response = ScheduledDate.objects.filter(date__startswith=date).values()
    return Response(response)

Entity Framework. Delete all rows in table

var list = db.Discounts.ToList().Select(x => x as Discount);
foreach (var item in list)
{
    db.Discounts.Remove(item);
}
db.SaveChanges();

Git fetch remote branch

If you are trying to "checkout" a new remote branch (that exists only on the remote, but not locally), here's what you'll need:

git fetch origin
git checkout --track origin/<remote_branch_name>

This assumes you want to fetch from origin. If not, replace origin by your remote name.

Sound effects in JavaScript / HTML5

Sounds like what you want is multi-channel sounds. Let's suppose you have 4 channels (like on really old 16-bit games), I haven't got round to playing with the HTML5 audio feature yet, but don't you just need 4 <audio> elements, and cycle which is used to play the next sound effect? Have you tried that? What happens? If it works: To play more sounds simultaneously, just add more <audio> elements.

I have done this before without the HTML5 <audio> element, using a little Flash object from http://flash-mp3-player.net/ - I wrote a music quiz (http://webdeavour.appspot.com/) and used it to play clips of music when the user clicked the button for the question. Initially I had one player per question, and it was possible to play them over the top of each other, so I changed it so there was only one player, which I pointed at different music clips.

How do I keep jQuery UI Accordion collapsed by default?

Add the active: false option (documentation)..

$("#accordion").accordion({ header: "h3", collapsible: true, active: false });

Best way to integrate Python and JavaScript?

PyExecJS is able to use each of PyV8, Node, JavaScriptCore, SpiderMonkey, JScript.

>>> import execjs
>>> execjs.eval("'red yellow blue'.split(' ')")
['red', 'yellow', 'blue']
>>> execjs.get().name
'Node.js (V8)'