Programs & Examples On #File transfer

Is a generic term for the act of transmitting files over a computer network or the Internet.

how to achieve transfer file between client and server using java socket

Reading quickly through the source it seems that you're not far off. The following link should help (I did something similar but for FTP). For a file send from server to client, you start off with a file instance and an array of bytes. You then read the File into the byte array and write the byte array to the OutputStream which corresponds with the InputStream on the client's side.

http://www.rgagnon.com/javadetails/java-0542.html

Edit: Here's a working ultra-minimalistic file sender and receiver. Make sure you understand what the code is doing on both sides.

package filesendtest;

import java.io.*;
import java.net.*;

class TCPServer {

    private final static String fileToSend = "C:\\test1.pdf";

    public static void main(String args[]) {

        while (true) {
            ServerSocket welcomeSocket = null;
            Socket connectionSocket = null;
            BufferedOutputStream outToClient = null;

            try {
                welcomeSocket = new ServerSocket(3248);
                connectionSocket = welcomeSocket.accept();
                outToClient = new BufferedOutputStream(connectionSocket.getOutputStream());
            } catch (IOException ex) {
                // Do exception handling
            }

            if (outToClient != null) {
                File myFile = new File( fileToSend );
                byte[] mybytearray = new byte[(int) myFile.length()];

                FileInputStream fis = null;

                try {
                    fis = new FileInputStream(myFile);
                } catch (FileNotFoundException ex) {
                    // Do exception handling
                }
                BufferedInputStream bis = new BufferedInputStream(fis);

                try {
                    bis.read(mybytearray, 0, mybytearray.length);
                    outToClient.write(mybytearray, 0, mybytearray.length);
                    outToClient.flush();
                    outToClient.close();
                    connectionSocket.close();

                    // File sent, exit the main method
                    return;
                } catch (IOException ex) {
                    // Do exception handling
                }
            }
        }
    }
}

package filesendtest;

import java.io.*;
import java.io.ByteArrayOutputStream;
import java.net.*;

class TCPClient {

    private final static String serverIP = "127.0.0.1";
    private final static int serverPort = 3248;
    private final static String fileOutput = "C:\\testout.pdf";

    public static void main(String args[]) {
        byte[] aByte = new byte[1];
        int bytesRead;

        Socket clientSocket = null;
        InputStream is = null;

        try {
            clientSocket = new Socket( serverIP , serverPort );
            is = clientSocket.getInputStream();
        } catch (IOException ex) {
            // Do exception handling
        }

        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        if (is != null) {

            FileOutputStream fos = null;
            BufferedOutputStream bos = null;
            try {
                fos = new FileOutputStream( fileOutput );
                bos = new BufferedOutputStream(fos);
                bytesRead = is.read(aByte, 0, aByte.length);

                do {
                        baos.write(aByte);
                        bytesRead = is.read(aByte);
                } while (bytesRead != -1);

                bos.write(baos.toByteArray());
                bos.flush();
                bos.close();
                clientSocket.close();
            } catch (IOException ex) {
                // Do exception handling
            }
        }
    }
}

Related

Byte array of unknown length in java

Edit: The following could be used to fingerprint small files before and after transfer (use SHA if you feel it's necessary):

public static String md5String(File file) {
    try {
        InputStream fin = new FileInputStream(file);
        java.security.MessageDigest md5er = MessageDigest.getInstance("MD5");
        byte[] buffer = new byte[1024];
        int read;
        do {
            read = fin.read(buffer);
            if (read > 0) {
                md5er.update(buffer, 0, read);
            }
        } while (read != -1);
        fin.close();
        byte[] digest = md5er.digest();
        if (digest == null) {
            return null;
        }
        String strDigest = "0x";
        for (int i = 0; i < digest.length; i++) {
            strDigest += Integer.toString((digest[i] & 0xff)
                    + 0x100, 16).substring(1).toUpperCase();
        }
        return strDigest;
    } catch (Exception e) {
        return null;
    }
}

scp from Linux to Windows

Open bash window. Preferably git bash. write

scp username@remote_ip:/directory_of_file/filename 'windows_location_you_want_to_store_the_file'

Example:

Suppose your username is jewel

your IP is 176.35.96.32

your remote file location is /usr/local/forme

your filename is logs.zip

and you want to store in your windows PC's D drive forme folder then the command will be

scp [email protected]:/usr/local/forme/logs.zip 'D:/forme'

**Keep the local file directory inside single quote.

Transfer files to/from session I'm logged in with PuTTY

Same everyday problem.

I just created a simple vc project to solve this problem.

It copies the file as Base64 encoded data directly to the clipboard, and then this can be pasted into the PuTTY console and decoded on the remote side.

This solution is for relatively small files (relative to the connection speed to your remote console).

Installation:

Download clip_b64.exe and place it in the SendTo folder (or a .lnk shortcut to it). To open this folder, in the address bar of the explorer, enter shell:sendto or %appdata%\Microsoft\Windows\SendTo.

You may need to install VC 2017 redist to run it, or use the statically linked clip_b64s.exe execution.

Usage:

On the local machine:

In the File Explorer, right-click the file you are transferring to open the context menu, then go to the "Send To" section and select Clip_B64 from the list.

On the remote console (over putty-ssh link):

Run the shell command base64 -d > file-name-you-want and right-click in the console (or press Shift + Insert) to place the clipboard content in it, and then press Ctrl + D to finish.

voila

Comparing HTTP and FTP for transferring files

Both of them uses TCP as a transport protocol, but HTTP uses a persistent connection, which makes the performance of the TCP better.

Viewing root access files/folders of android on windows

I was looking long and hard for a solution to this problem and the best I found was a root FTP server on the phone that you connect to on Windows with an FTP client like FileZilla, on the same WiFi network of course.

The root FTP server app I ended up using is FTP Droid. I tried a lot of other FTP apps with bigger download numbers but none of them worked for me for whatever reason. So install this app and set a user with home as / or wherever you want.

Then make note of the phone IP and connect with FileZilla and you should have access to the root of the phone. The biggest benefit I found is I can download entire folders and FTP will just queue it up and take care of it. So I downloaded all of my /data/data/ folder when I was looking for an app and could search on my PC. Very handy.

SFTP file transfer using Java JSch

Usage:

sftp("file:/C:/home/file.txt", "ssh://user:pass@host/home");
sftp("ssh://user:pass@host/home/file.txt", "file:/C:/home");

Implementation

scp copy directory to another server with private key auth

The command looks quite fine. Could you try to run -v (verbose mode) and then we can figure out what it is wrong on the authentication?

Also as mention in the other answer, maybe could be this issue - that you need to convert the keys (answered already here): How to convert SSH keypairs generated using PuttyGen(Windows) into key-pairs used by ssh-agent and KeyChain(Linux) OR http://winscp.net/eng/docs/ui_puttygen (depending what you need)

rsync error: failed to set times on "/foo/bar": Operation not permitted

The issue is probably due to /foo/bar not being owned by the writing process on a remote darwin (OS X) system. A solution to the issue is to set adequate owner on the remote site.

Since this answer has been voted, and therefore has been hopefully useful to someone, I'm extending it to make it clearer.

The reason why this happens is that rsync is probably trying to set an arbitrary modification time (mtime) when copying files.

In order to do this darwin's system utime() function requires that the writing process effective uid is either the same as the file uid or super user's one, see opengroup utime's page. Check this discussion on rsync mailing list as reference.

How do you make div elements display inline?

You should use <span> instead of <div> for correct way of inline. because div is a block level element, and your requirement is for inline-block level elements.

Here is html code as per your requirements :

<div class="main-div">
 <div>foo</div>
 <div>bar</div>
 <div>baz</div>`
</div>

You've two way to do this


  • using simple display:inline-block;
  • or using float:left;

so you've to change display property display:inline-block; forcefully

Example one

div {
    display: inline-block;
}

Example two

div {
    float: left;
}

you need to clear float

.main-div:after {
    content: "";
    clear: both;
    display: table;
}

Cannot connect to MySQL Workbench on mac. Can't connect to MySQL server on '127.0.0.1' (61) Mac Macintosh

Try restarting the mysql or starting it if it wasn't started already. Type this within terminal.

mysql.server restart

To auto start go to the following link below:

How to auto-load MySQL on startup on OS X Yosemite / El Capitan

What is the .idea folder?

There is no problem in deleting this. It's not only the WebStorm IDE creating this file, but also PhpStorm and all other of JetBrains' IDEs.

It is safe to delete it but if your project is from GitLab or GitHub then you will see a warning.

ConnectivityManager getNetworkInfo(int) deprecated

There is an update to this answer as of March 2020 that supports API.15 through API.29, you can find it following to the original answer

Answer February 2019

To check if you're online:

boolean isOnline() {
    // Checking internet connectivity
    ConnectivityManager connectivityMgr = (ConnectivityManager) this.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetwork = null;
    if (connectivityMgr != null) {
        activeNetwork = connectivityMgr.getActiveNetworkInfo();
    }
    return activeNetwork != null;
}

Kotlin:

fun isOnline(): Boolean {
    val connectivityMgr = getSystemService(CONNECTIVITY_SERVICE) as ConnectivityManager

    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.P) {
        return connectivityMgr.activeNetworkInfo != null

    } else {

        for (network in connectivityMgr.allNetworks) { // added in API 21 (Lollipop)
            val networkCapabilities: NetworkCapabilities? =
                connectivityMgr.getNetworkCapabilities(network)
            return (networkCapabilities!!.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET) &&
                    networkCapabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED) &&
                    (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)
                            || networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)
                            || networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET)))
        }
    }
    return false
}

To get the type of internet connectivity before/after android M

void internetType() {
    // Checking internet connectivity
    ConnectivityManager connectivityMgr = (ConnectivityManager) this.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetwork = null;
    if (connectivityMgr != null) {
        activeNetwork = connectivityMgr.getActiveNetworkInfo();
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            NetworkCapabilities nc = connectivityMgr.getNetworkCapabilities(connectivityMgr.getActiveNetwork());
            if (nc.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
                // connected to mobile data
            } else if (nc.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
                // connected to wifi
            }
        } else {
            if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
                // connected to wifi
            } else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
                // connected to mobile data
            }
        }
    }
}

All cases requires a permission to access network state

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Update December 2020

As NetworkInfo is deprecated and as of API 29 from now we have to use ConnectivityManager.NetworkCallback with its network state change onAvailable() & onLost() callbacks.

Usage:

  • You can either use this library, or directly use the below utility class which is a part of this library.

Features

  • It's LifeCycle conscious by implementing LifecycleObserver to avoid memory leakage by doing some cleanup in onDestroy() method.
  • It supports from API 15 (Ice Cream Sandwich) through API 29 (Android Q)
  • For APIs prior to API 21, it uses a context-based BoradcastReceiver and NetworkInfo, and uses ConnectivityManager.NetworkCallback for API 21 and above.
  • When both WiFi and cellular networks are on, then the connectivity listener won't interrupt when the WiFi is disconnected while transitioning to the cellular network.
  • When the cellular network is on, then the connectivity listener won't interrupt when the WiFi is connected and being the active network (as this is the preferred network).
  • If you're going to use the library, then no need to include this permission android.permission.ACCESS_NETWORK_STATE; but you have to include it if you're going to use the utility class.

Capabilities

  • Get the current connectivity status (online / offline).
  • Continuous checking/listening to the internet connection and triggering a callback when the device goes offline or online.
  • Get the type of the active internet connection (WiFi or Cellular).
  • Get the type of all available networks (WiFi or Cellular). >> Only supported on API 21+
  • Get the number of all available networks >> Only supported on API 21+
@RequiresApi(api = Build.VERSION_CODES.ICE_CREAM_SANDWICH_MR1)
public class ConnectionUtil implements LifecycleObserver {

    private static final String TAG = "LOG_TAG";
    private ConnectivityManager mConnectivityMgr;
    private Context mContext;
    private NetworkStateReceiver mNetworkStateReceiver;
    
    /*
     * boolean indicates if my device is connected to the internet or not
     * */
    private boolean mIsConnected = false;
    private ConnectionMonitor mConnectionMonitor;


    /**
     * Indicates there is no available network.
     */
    private static final int NO_NETWORK_AVAILABLE = -1;


    /**
     * Indicates this network uses a Cellular transport.
     */
    public static final int TRANSPORT_CELLULAR = 0;


    /**
     * Indicates this network uses a Wi-Fi transport.
     */
    public static final int TRANSPORT_WIFI = 1;


    public interface ConnectionStateListener {
        void onAvailable(boolean isAvailable);
    }


    public ConnectionUtil(Context context) {
        mContext = context;
        mConnectivityMgr = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        ((AppCompatActivity) mContext).getLifecycle().addObserver(this);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            mConnectionMonitor = new ConnectionMonitor();
            NetworkRequest networkRequest = new NetworkRequest.Builder()
                    .addTransportType(NetworkCapabilities.TRANSPORT_CELLULAR)
                    .addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
                    .build();
            mConnectivityMgr.registerNetworkCallback(networkRequest, mConnectionMonitor);
        }

    }


    /**
     * Returns true if connected to the internet, and false otherwise
     *
     * <p>
     * NetworkInfo is deprecated in API 29
     * https://developer.android.com/reference/android/net/NetworkInfo
     * <p>
     * getActiveNetworkInfo() is deprecated in API 29
     * https://developer.android.com/reference/android/net/ConnectivityManager#getActiveNetworkInfo()
     * <p>
     * getNetworkInfo(int) is deprecated as of API 23
     * https://developer.android.com/reference/android/net/ConnectivityManager#getNetworkInfo(int)
     */
    public boolean isOnline() {

        mIsConnected = false;

        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.P) {
            // Checking internet connectivity
            NetworkInfo activeNetwork = null;
            if (mConnectivityMgr != null) {
                activeNetwork = mConnectivityMgr.getActiveNetworkInfo(); // Deprecated in API 29
            }
            mIsConnected = activeNetwork != null;

        } else {
            Network[] allNetworks = mConnectivityMgr.getAllNetworks(); // added in API 21 (Lollipop)

            for (Network network : allNetworks) {
                NetworkCapabilities networkCapabilities = mConnectivityMgr.getNetworkCapabilities(network);
                if (networkCapabilities != null) {
                    if (networkCapabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET) &&
                            networkCapabilities.hasCapability(NET_CAPABILITY_VALIDATED))
                        if (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)
                                || networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)
                                || networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET))
                            mIsConnected = true;
                }
            }

        }

        return mIsConnected;

    }


    /**
     * Returns
     * <p> <p>
     * <p><p> NO_NETWORK_AVAILABLE >>> when you're offline
     * <p><p> TRANSPORT_CELLULAR >> When Cellular is the active network
     * <p><p> TRANSPORT_WIFI >> When Wi-Fi is the Active network
     * <p>
     */
    public int getActiveNetwork() {

        NetworkInfo activeNetwork = mConnectivityMgr.getActiveNetworkInfo(); // Deprecated in API 29
        if (activeNetwork != null)

            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                NetworkCapabilities capabilities = mConnectivityMgr.getNetworkCapabilities(mConnectivityMgr.getActiveNetwork());
                if (capabilities != null)
                    if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
                        // connected to mobile data
                        return TRANSPORT_CELLULAR;

                    } else if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
                        // connected to wifi
                        return TRANSPORT_WIFI;
                    }

            } else {
                if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) { // Deprecated in API 28
                    // connected to mobile data
                    return TRANSPORT_CELLULAR;

                } else if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) { // Deprecated in API 28
                    // connected to wifi
                    return TRANSPORT_WIFI;
                }
            }
        return NO_NETWORK_AVAILABLE;
    }


    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
    public int getAvailableNetworksCount() {

        int count = 0;

        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
            Network[] allNetworks = mConnectivityMgr.getAllNetworks(); // added in API 21 (Lollipop)
            for (Network network : allNetworks) {
                NetworkCapabilities networkCapabilities = mConnectivityMgr.getNetworkCapabilities(network);
                if (networkCapabilities != null)
                    if (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)
                            || networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR))
                        count++;
            }

        }

        return count;
    }
    

    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
    public List<Integer> getAvailableNetworks() {

        List<Integer> activeNetworks = new ArrayList<>();

        Network[] allNetworks; // added in API 21 (Lollipop)
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
            allNetworks = mConnectivityMgr.getAllNetworks();
            for (Network network : allNetworks) {
                NetworkCapabilities networkCapabilities = mConnectivityMgr.getNetworkCapabilities(network);
                if (networkCapabilities != null) {
                    if (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI))
                        activeNetworks.add(TRANSPORT_WIFI);

                    if (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR))
                        activeNetworks.add(TRANSPORT_CELLULAR);

                }
            }
        }

        return activeNetworks;
    }


    public void onInternetStateListener(ConnectionStateListener listener) {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
            mNetworkStateReceiver = new NetworkStateReceiver(listener);
            IntentFilter intentFilter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
            mContext.registerReceiver(mNetworkStateReceiver, intentFilter);

        } else {
            mConnectionMonitor.setOnConnectionStateListener(listener);
        }
    }


    @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
    public void onDestroy() {
        Log.d(TAG, "onDestroy");
        ((AppCompatActivity) mContext).getLifecycle().removeObserver(this);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            if (mConnectionMonitor != null)
                mConnectivityMgr.unregisterNetworkCallback(mConnectionMonitor);
        } else {
            if (mNetworkStateReceiver != null)
                mContext.unregisterReceiver(mNetworkStateReceiver);
        }

    }


    public class NetworkStateReceiver extends BroadcastReceiver {

        ConnectionStateListener mListener;

        public NetworkStateReceiver(ConnectionStateListener listener) {
            mListener = listener;
        }

        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getExtras() != null) {

                NetworkInfo activeNetworkInfo = mConnectivityMgr.getActiveNetworkInfo(); // deprecated in API 29

                /*
                 * activeNetworkInfo.getState() deprecated in API 28
                 * NetworkInfo.State.CONNECTED deprecated in API 29
                 * */
                if (!mIsConnected && activeNetworkInfo != null && activeNetworkInfo.getState() == NetworkInfo.State.CONNECTED) {
                    Log.d(TAG, "onReceive: " + "Connected To: " + activeNetworkInfo.getTypeName());
                    mIsConnected = true;
                    mListener.onAvailable(true);

                } else if (intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY, Boolean.FALSE)) {
                    if (!isOnline()) {
                        mListener.onAvailable(false);
                        mIsConnected = false;
                    }

                }

            }
        }
    }


    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
    public class ConnectionMonitor extends ConnectivityManager.NetworkCallback {

        private ConnectionStateListener mConnectionStateListener;

        void setOnConnectionStateListener(ConnectionStateListener connectionStateListener) {
            mConnectionStateListener = connectionStateListener;
        }

        @Override
        public void onAvailable(@NonNull Network network) {

            if (mIsConnected)
                return;

            Log.d(TAG, "onAvailable: ");

            if (mConnectionStateListener != null) {
                mConnectionStateListener.onAvailable(true);
                mIsConnected = true;
            }

        }

        @Override
        public void onLost(@NonNull Network network) {

            if (getAvailableNetworksCount() == 0) {
                if (mConnectionStateListener != null)
                    mConnectionStateListener.onAvailable(false);
                mIsConnected = false;
            }

        }

    }

}

Kotlin version


class ConnectionUtil(var mContext: Context) : LifecycleObserver {

    private val TAG = "LOG_TAG"

    companion object NetworkType {

        /**
         * Indicates this network uses a Cellular transport.
         */
        const val TRANSPORT_CELLULAR = 0

        /**
         * Indicates this network uses a Wi-Fi transport.
         */
       const val TRANSPORT_WIFI = 1

    }

    private var mConnectivityMgr: ConnectivityManager? = null

    //    private var mContext: Context? = null
    private var mNetworkStateReceiver: NetworkStateReceiver? = null

    /*
     * boolean indicates if my device is connected to the internet or not
     * */
    private var mIsConnected = false
    private var mConnectionMonitor: ConnectionMonitor? = null


    /**
     * Indicates there is no available network.
     */
    private val NO_NETWORK_AVAILABLE = -1


    interface ConnectionStateListener {
        fun onAvailable(isAvailable: Boolean)
    }

    init {
        mConnectivityMgr =
            mContext.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
        (mContext as AppCompatActivity?)!!.lifecycle.addObserver(this)
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            mConnectionMonitor = ConnectionMonitor()
            val networkRequest = NetworkRequest.Builder()
                .addTransportType(NetworkCapabilities.TRANSPORT_CELLULAR)
                .addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
                .build()
            mConnectivityMgr!!.registerNetworkCallback(networkRequest, mConnectionMonitor!!)
        }
    }


    /**
     * Returns true if connected to the internet, and false otherwise
     *
     * NetworkInfo is deprecated in API 29
     * https://developer.android.com/reference/android/net/NetworkInfo
     *
     * getActiveNetworkInfo() is deprecated in API 29
     * https://developer.android.com/reference/android/net/ConnectivityManager#getActiveNetworkInfo()
     *
     * getNetworkInfo(int) is deprecated as of API 23
     * https://developer.android.com/reference/android/net/ConnectivityManager#getNetworkInfo(int)
     */
    fun isOnline(): Boolean {
        mIsConnected = false
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.P) {
            // Checking internet connectivity
            var activeNetwork: NetworkInfo? = null
            if (mConnectivityMgr != null) {
                activeNetwork = mConnectivityMgr!!.activeNetworkInfo // Deprecated in API 29
            }
            mIsConnected = activeNetwork != null
        } else {
            val allNetworks = mConnectivityMgr!!.allNetworks // added in API 21 (Lollipop)
            for (network in allNetworks) {
                val networkCapabilities = mConnectivityMgr!!.getNetworkCapabilities(network)
                if (networkCapabilities != null) {
                    if (networkCapabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET) &&
                        networkCapabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED)
                    ) 
                        if (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)
                            || networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)
                            || networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET)
                        ) mIsConnected = true
                }
            }
        }
        return mIsConnected
    }


    /**
     * Returns:
     *
     * NO_NETWORK_AVAILABLE >>> when you're offline
     * TRANSPORT_CELLULAR >> When Cellular is the active network
     * TRANSPORT_WIFI >> When Wi-Fi is the Active network
     */
    fun getActiveNetwork(): Int {
        val activeNetwork = mConnectivityMgr!!.activeNetworkInfo // Deprecated in API 29
        if (activeNetwork != null) if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            val capabilities = mConnectivityMgr!!.getNetworkCapabilities(
                mConnectivityMgr!!.activeNetwork
            )
            if (capabilities != null) if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
                // connected to mobile data
                return TRANSPORT_CELLULAR
            } else if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
                // connected to wifi
                return TRANSPORT_WIFI
            }
        } else {
            if (activeNetwork.type == ConnectivityManager.TYPE_MOBILE) { // Deprecated in API 28
                // connected to mobile data
                return TRANSPORT_CELLULAR
            } else if (activeNetwork.type == ConnectivityManager.TYPE_WIFI) { // Deprecated in API 28
                // connected to wifi
                return TRANSPORT_WIFI
            }
        }
        return NO_NETWORK_AVAILABLE
    }


    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
    fun getAvailableNetworksCount(): Int {
        var count = 0
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            val allNetworks = mConnectivityMgr!!.allNetworks // added in API 21 (Lollipop)
            for (network in allNetworks) {
                val networkCapabilities = mConnectivityMgr!!.getNetworkCapabilities(network)
                if (networkCapabilities != null) if (networkCapabilities.hasTransport(
                        NetworkCapabilities.TRANSPORT_WIFI
                    )
                    || networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)
                ) count++
            }
        }
        return count
    }

    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
    fun getAvailableNetworks(): List<Int> {
        val activeNetworks: MutableList<Int> = ArrayList()
        val allNetworks: Array<Network> // added in API 21 (Lollipop)
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            allNetworks = mConnectivityMgr!!.allNetworks
            for (network in allNetworks) {
                val networkCapabilities = mConnectivityMgr!!.getNetworkCapabilities(network)
                if (networkCapabilities != null) {
                    if (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) activeNetworks.add(
                        TRANSPORT_WIFI
                    )
                    if (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) activeNetworks.add(
                        TRANSPORT_CELLULAR
                    )
                }
            }
        }
        return activeNetworks
    }


    fun onInternetStateListener(listener: ConnectionStateListener) {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
            mNetworkStateReceiver = NetworkStateReceiver(listener)
            val intentFilter = IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION)
            mContext.registerReceiver(mNetworkStateReceiver, intentFilter)
        } else {
            mConnectionMonitor!!.setOnConnectionStateListener(listener)
        }
    }


    @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
    fun onDestroy() {
        Log.d(TAG, "onDestroy")
        (mContext as AppCompatActivity?)!!.lifecycle.removeObserver(this)
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            if (mConnectionMonitor != null) mConnectivityMgr!!.unregisterNetworkCallback(
                mConnectionMonitor!!
            )
        } else {
            if (mNetworkStateReceiver != null) mContext.unregisterReceiver(mNetworkStateReceiver)
        }
    }


    inner class NetworkStateReceiver(var mListener: ConnectionStateListener) :
        BroadcastReceiver() {
        override fun onReceive(context: Context, intent: Intent) {
            if (intent.extras != null) {
                val activeNetworkInfo: NetworkInfo? =
                    mConnectivityMgr?.getActiveNetworkInfo() // deprecated in API 29

                /*
                 * activeNetworkInfo.getState() deprecated in API 28
                 * NetworkInfo.State.CONNECTED deprecated in API 29
                 * */if (!mIsConnected && activeNetworkInfo != null && activeNetworkInfo.state == NetworkInfo.State.CONNECTED) {
                    mIsConnected = true
                    mListener.onAvailable(true)
                } else if (intent.getBooleanExtra(
                        ConnectivityManager.EXTRA_NO_CONNECTIVITY,
                        java.lang.Boolean.FALSE
                    )
                ) {
                    if (!isOnline()) {
                        mListener.onAvailable(false)
                        mIsConnected = false
                    }
                }
            }
        }
    }

    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
    inner class ConnectionMonitor : NetworkCallback() {
        private var mConnectionStateListener: ConnectionStateListener? = null
        fun setOnConnectionStateListener(connectionStateListener: ConnectionStateListener?) {
            mConnectionStateListener = connectionStateListener
        }

        override fun onAvailable(network: Network) {
            if (mIsConnected) return
            Log.d(TAG, "onAvailable: ")
            if (mConnectionStateListener != null) {
                mConnectionStateListener!!.onAvailable(true)
                mIsConnected = true
            }
        }

        override fun onLost(network: Network) {
            if (getAvailableNetworksCount() == 0) {
                mConnectionStateListener?.onAvailable(false)
                mIsConnected = false
            }
        }
    }

}

Visual studio equivalent of java System.out

Use Either Debug.WriteLine() or Trace.WriteLine(). If in release mode, only the latter will appear in the output window, in debug mode, both will.

How to change the project in GCP using CLI commands

The selected answer doesn't help if you don't know the name of projects you have added gcloud already. My flow is to list the active projects, then switch to the one I want.

gcloud config configurations list

gcloud config configurations activate [NAME]
where [NAME] is listed from the prior command.

How to delete multiple values from a vector?

instead of

x <- x[! x %in% c(2,3,5)]

using the packages purrr and magrittr, you can do:

your_vector %<>% discard(~ .x %in% c(2,3,5))

this allows for subsetting using the vector name only once. And you can use it in pipes :)

What is the best JavaScript code to create an img element

var img = new Image(1,1); // width, height values are optional params 
img.src = 'http://www.testtrackinglink.com';

Condition within JOIN or WHERE

The relational algebra allows interchangeability of the predicates in the WHERE clause and the INNER JOIN, so even INNER JOIN queries with WHERE clauses can have the predicates rearrranged by the optimizer so that they may already be excluded during the JOIN process.

I recommend you write the queries in the most readable way possible.

Sometimes this includes making the INNER JOIN relatively "incomplete" and putting some of the criteria in the WHERE simply to make the lists of filtering criteria more easily maintainable.

For example, instead of:

SELECT *
FROM Customers c
INNER JOIN CustomerAccounts ca
    ON ca.CustomerID = c.CustomerID
    AND c.State = 'NY'
INNER JOIN Accounts a
    ON ca.AccountID = a.AccountID
    AND a.Status = 1

Write:

SELECT *
FROM Customers c
INNER JOIN CustomerAccounts ca
    ON ca.CustomerID = c.CustomerID
INNER JOIN Accounts a
    ON ca.AccountID = a.AccountID
WHERE c.State = 'NY'
    AND a.Status = 1

But it depends, of course.

How can I create a blank/hardcoded column in a sql query?

Thank you, in PostgreSQL this works for boolean

SELECT
hat,
shoe,
boat,
false as placeholder
FROM
objects

Update statement with inner join on Oracle

This following syntax works for me.

UPDATE
(SELECT A.utl_id,
    b.utl1_id
    FROM trb_pi_joint A
    JOIN trb_tpr B
    ON A.tp_id=B.tp_id Where A.pij_type=2 and a.utl_id is null
)
SET utl_id=utl1_id;

change html input type by JS?

_x000D_
_x000D_
$(".show-pass").click(function (e) {_x000D_
    e.preventDefault();_x000D_
    var type = $("#signupform-password").attr('type');_x000D_
    switch (type) {_x000D_
        case 'password':_x000D_
        {_x000D_
            $("#signupform-password").attr('type', 'text');_x000D_
            return;_x000D_
        }_x000D_
        case 'text':_x000D_
        {_x000D_
            $("#signupform-password").attr('type', 'password');_x000D_
            return;_x000D_
        }_x000D_
    }_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<input type="text" name="password" class="show-pass">
_x000D_
_x000D_
_x000D_

Embedding SVG into ReactJS

There is a package that converts it for you and returns the svg as a string to implement into your reactJS file.

https://www.npmjs.com/package/convert-svg-react

C# Regex for Guid

This one is quite simple and does not require a delegate as you say.

resultString = Regex.Replace(subjectString, 
     @"(?im)^[{(]?[0-9A-F]{8}[-]?(?:[0-9A-F]{4}[-]?){3}[0-9A-F]{12}[)}]?$", 
     "'$0'");

This matches the following styles, which are all equivalent and acceptable formats for a GUID.

ca761232ed4211cebacd00aa0057b223
CA761232-ED42-11CE-BACD-00AA0057B223
{CA761232-ED42-11CE-BACD-00AA0057B223}
(CA761232-ED42-11CE-BACD-00AA0057B223)

Update 1

@NonStatic makes the point in the comments that the above regex will match false positives which have a wrong closing delimiter.

This can be avoided by regex conditionals which are broadly supported.

Conditionals are supported by the JGsoft engine, Perl, PCRE, Python, and the .NET framework. Ruby supports them starting with version 2.0. Languages such as Delphi, PHP, and R that have regex features based on PCRE also support conditionals. (source http://www.regular-expressions.info/conditional.html)

The regex that follows Will match

{123}
(123)
123

And will not match

{123)
(123}
{123
(123
123}
123)

Regex:

^({)?(\()?\d+(?(1)})(?(2)\))$

The solutions is simplified to match only numbers to show in a more clear way what is required if needed.

How to change row color in datagridview?

You need to loop through the rows in the datagridview and then compare values of columns 7 and 10 on each row.

Try this:

foreach (DataGridViewRow row in vendorsDataGridView.Rows) 
     if (Convert.ToInt32(row.Cells[7].Value) < Convert.ToInt32(row.Cells[10].Value)) 
     {
         row.DefaultCellStyle.BackColor = Color.Red; 
     }

Has been blocked by CORS policy: Response to preflight request doesn’t pass access control check

The CORS issue should be fixed in the backend. Temporary workaround uses this option.

  1. Go to C:\Program Files\Google\Chrome\Application

  2. Open command prompt

  3. Execute the command chrome.exe --disable-web-security --user-data-dir="c:/ChromeDevSession"

Using the above option, you can able to open new chrome without security. this chrome will not throw any cors issue.

enter image description here

Remove all special characters from a string

This should do what you're looking for:

function clean($string) {
   $string = str_replace(' ', '-', $string); // Replaces all spaces with hyphens.

   return preg_replace('/[^A-Za-z0-9\-]/', '', $string); // Removes special chars.
}

Usage:

echo clean('a|"bc!@£de^&$f g');

Will output: abcdef-g

Edit:

Hey, just a quick question, how can I prevent multiple hyphens from being next to each other? and have them replaced with just 1?

function clean($string) {
   $string = str_replace(' ', '-', $string); // Replaces all spaces with hyphens.
   $string = preg_replace('/[^A-Za-z0-9\-]/', '', $string); // Removes special chars.

   return preg_replace('/-+/', '-', $string); // Replaces multiple hyphens with single one.
}

Re-sign IPA (iPhone)

In 2020, I did it with Fastlane -

Here is the command I used

$ fastlane run resign ipa:"/Users/my_user/path/to/app.ipa" signing_identity:"iPhone Distribution: MY Company (XXXXXXXX)" provisioning_profile:"/Users/my_user/path/to/profile.mobileprovision" bundle_id:com.company.new.bundle.name

Full docs here - https://docs.fastlane.tools/actions/resign/

If Browser is Internet Explorer: run an alternative script instead

Note that you can also determine in pure js in what browser you script is beeing executed through : window.navigator.userAgent

However, that's not a recommended way as it's configurable in the browser settings. More info available there: https://developer.mozilla.org/fr/docs/DOM/window.navigator.userAgent

Mocking member variables of a class using Mockito

If you look closely at your code you'll see that the second property in your test is still an instance of Second, not a mock (you don't pass the mock to first in your code).

The simplest way would be to create a setter for second in First class and pass it the mock explicitly.

Like this:

public class First {

    Second second ;

    public First(){
        second = new Second();
    }

    public String doSecond(){
        return second.doSecond();
    }

    public void setSecond(Second second) {
        this.second = second;
    }


}

class Second {

    public String doSecond(){
        return "Do Something";
    }
}

....

public void testFirst(){
Second sec = mock(Second.class);
when(sec.doSecond()).thenReturn("Stubbed Second");


First first = new First();
first.setSecond(sec)
assertEquals("Stubbed Second", first.doSecond());
}

Another would be to pass a Second instance as First's constructor parameter.

If you can't modify the code, I think the only option would be to use reflection:

public void testFirst(){
    Second sec = mock(Second.class);
    when(sec.doSecond()).thenReturn("Stubbed Second");


    First first = new First();
    Field privateField = PrivateObject.class.
        getDeclaredField("second");

    privateField.setAccessible(true);

    privateField.set(first, sec);

    assertEquals("Stubbed Second", first.doSecond());
}

But you probably can, as it's rare to do tests on code you don't control (although one can imagine a scenario where you have to test an external library cause it's author didn't :))

How can you create pop up messages in a batch script?

You can take advantage of CSCRIPT.EXE or WSCRIPT.EXE (which have been present in every version of Windows since, I believe, Windows 95) like this:

echo msgbox "Hey! Here is a message!" > %tmp%\tmp.vbs
cscript /nologo %tmp%\tmp.vbs
del %tmp%\tmp.vbs

or

echo msgbox "Hey! Here is a message!" > %tmp%\tmp.vbs
wscript %tmp%\tmp.vbs
del %tmp%\tmp.vbs

You could also choose the more customizeable PopUp command. This example gives you a 10 second window to click OK, before timing out:

echo set WshShell = WScript.CreateObject("WScript.Shell") > %tmp%\tmp.vbs
echo WScript.Quit (WshShell.Popup( "You have 10 seconds to Click 'OK'." ,10 ,"Click OK", 0)) >> %tmp%\tmp.vbs
cscript /nologo %tmp%\tmp.vbs
if %errorlevel%==1 (
  echo You Clicked OK
) else (
  echo The Message timed out.
)
del %tmp%\tmp.vbs

In their above context, both cscript and wscript will act the same. When called from a batch file, bot cscript and wscript will pause the batch file until they finish their script, then allow the file to continue.

When called manually from the command prompt, cscript will not return control to the command prompt until it is finished, while wscript will create a seprate thread for the execution of it's script, returning control to the command prompt even before it's script has finished.

Other methods discussed in this thread do not cause the execution of batch files to pause while waiting for the message to be clicked on. Your selection will be dictated by your needs.

Note: Using this method, multiple button and icon configurations are available to cover various yes/no/cancel/abort/retry queries to the user: https://technet.microsoft.com/en-us/library/ee156593.aspx

enter image description here

Singletons vs. Application Context in Android?

I very much disagree with Dianne Hackborn's response. We are bit by bit removing all singletons from our project in favor of lightweight, task scoped objects which can easiliy be re-created when you actually need them.

Singletons are a nightmare for testing and, if lazily initialized, will introduce "state indeterminism" with subtle side effects (which may suddenly surface when moving calls to getInstance() from one scope to another). Visibility has been mentioned as another problem, and since singletons imply "global" (= random) access to shared state, subtle bugs may arise when not properly synchronized in concurrent applications.

I consider it an anti-pattern, it's a bad object-oriented style that essentially amounts to maintaining global state.

To come back to your question:

Although the app context can be considered a singleton itself, it is framework-managed and has a well defined life-cycle, scope, and access path. Hence I believe that if you do need to manage app-global state, it should go here, nowhere else. For anything else, rethink if you really need a singleton object, or if it would also be possible to rewrite your singleton class to instead instantiate small, short-lived objects that perform the task at hand.

Getting URL hash location, and using it in jQuery

For those who are looking for pure javascript solution

 document.getElementById(location.hash.substring(1)).style.display = 'block'

Hope this saves you some time.

Create two-dimensional arrays and access sub-arrays in Ruby

I'm quite sure this can be very simple

2.0.0p247 :032 > list = Array.new(5)

 => [nil, nil, nil, nil, nil] 

2.0.0p247 :033 > list.map!{ |x| x = [0] }

 => [[0], [0], [0], [0], [0]] 

2.0.0p247 :034 > list[0][0]

  => 0

Convert Newtonsoft.Json.Linq.JArray to a list of specific object type

using Newtonsoft.Json.Linq;
using System.Linq;
using System.IO;
using System.Collections.Generic;

public List<string> GetJsonValues(string filePath, string propertyName)
{
  List<string> values = new List<string>();
  string read = string.Empty;
  using (StreamReader r = new StreamReader(filePath))
  {
    var json = r.ReadToEnd();
    var jObj = JObject.Parse(json);
    foreach (var j in jObj.Properties())
    {
      if (j.Name.Equals(propertyName))
      {
        var value = jObj[j.Name] as JArray;
        return values = value.ToObject<List<string>>();
      }
    }
    return values;
  }
}

How can I divide one column of a data frame through another?

Hadley Wickham

dplyr

packages is always a saver in case of data wrangling. To add the desired division as a third variable I would use mutate()

d <- mutate(d, new = min / count2.freq)

Can I automatically increment the file build version when using Visual Studio?

In visual Studio 2008, the following works.

Find the AssemblyInfo.cs file and find these 2 lines:

[assembly: AssemblyVersion("1.0.0.0")]
[assembly: AssemblyFileVersion("1.0.0.0")]

You could try changing this to:

[assembly: AssemblyVersion("1.0.*")]
[assembly: AssemblyFileVersion("1.0.*")]

But this won't give you the desired result, you will end up with a Product Version of 1.0.* and a File Version of 1.0.0.0. Not what you want!

However, if you remove the second of these lines and just have:

[assembly: AssemblyVersion("1.0.*")]

Then the compiler will set the File Version to be equal to the Product Version and you will get your desired result of an automatically increment product and file version which are in sync. E.g. 1.0.3266.92689

<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)

C# Break out of foreach loop after X number of items

Why not just use a regular for loop?

for(int i = 0; i < 50 && i < listView.Items.Count; i++)
{
    ListViewItem lvi = listView.Items[i];
}

Updated to resolve bug pointed out by Ruben and Pragmatrix.

Add objects to an array of objects in Powershell

To append to an array, just use the += operator.

$Target += $TargetObject

Also, you need to declare $Target = @() before your loop because otherwise, it will empty the array every loop.

Python reading from a file and saving to utf-8

Process text to and from Unicode at the I/O boundaries of your program using open with the encoding parameter. Make sure to use the (hopefully documented) encoding of the file being read. The default encoding varies by OS (specifically, locale.getpreferredencoding(False) is the encoding used), so I recommend always explicitly using the encoding parameter for portability and clarity (Python 3 syntax below):

with open(filename, 'r', encoding='utf8') as f:
    text = f.read()

# process Unicode text

with open(filename, 'w', encoding='utf8') as f:
    f.write(text)

If still using Python 2 or for Python 2/3 compatibility, the io module implements open with the same semantics as Python 3's open and exists in both versions:

import io
with io.open(filename, 'r', encoding='utf8') as f:
    text = f.read()

# process Unicode text

with io.open(filename, 'w', encoding='utf8') as f:
    f.write(text)

Execute stored procedure with an Output parameter?

Check this, Where first two parameters are input parameters and 3rd one is Output parameter in Procedure definition.

DECLARE @PK_Code INT;
EXEC USP_Validate_Login  'ID', 'PWD', @PK_Code OUTPUT
SELECT @PK_Code

Java regular expression OR operator

You can just use the pipe on its own:

"string1|string2"

for example:

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string1|string2", "blah"));

Output:

blah, blah, string3

The main reason to use parentheses is to limit the scope of the alternatives:

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string(1|2)", "blah"));

has the same output. but if you just do this:

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string1|2", "blah"));

you get:

blah, stringblah, string3

because you've said "string1" or "2".

If you don't want to capture that part of the expression use ?::

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string(?:1|2)", "blah"));

Putting images with options in a dropdown list

I have found a crossbrowser compatible JQuery plugin here.

http://designwithpc.com/Plugins/ddSlick

probably useful in this scenario.

Go install fails with error: no install location for directory xxx outside GOPATH

I'm on Windows, and I got it by giving command go help gopath to cmd, and read the bold text in the instruction,

that is if code you wnat to install is at ..BaseDir...\SomeProject\src\basic\set, the GOPATH should not be the same location as code, it should be just Base Project DIR: ..BaseDir...\SomeProject.

The GOPATH environment variable lists places to look for Go code. On Unix, the value is a colon-separated string. On Windows, the value is a semicolon-separated string. On Plan 9, the value is a list.

If the environment variable is unset, GOPATH defaults to a subdirectory named "go" in the user's home directory ($HOME/go on Unix, %USERPROFILE%\go on Windows), unless that directory holds a Go distribution. Run "go env GOPATH" to see the current GOPATH.

See https://golang.org/wiki/SettingGOPATH to set a custom GOPATH.

Each directory listed in GOPATH must have a prescribed structure:

The src directory holds source code. The path below src determines the import path or executable name.

The pkg directory holds installed package objects. As in the Go tree, each target operating system and architecture pair has its own subdirectory of pkg (pkg/GOOS_GOARCH).

If DIR is a directory listed in the GOPATH, a package with source in DIR/src/foo/bar can be imported as "foo/bar" and has its compiled form installed to "DIR/pkg/GOOS_GOARCH/foo/bar.a".

The bin directory holds compiled commands. Each command is named for its source directory, but only the final element, not the entire path. That is, the command with source in DIR/src/foo/quux is installed into DIR/bin/quux, not DIR/bin/foo/quux. The "foo/" prefix is stripped so that you can add DIR/bin to your PATH to get at the installed commands. If the GOBIN environment variable is set, commands are installed to the directory it names instead of DIR/bin. GOBIN must be an absolute path.

Here's an example directory layout:

GOPATH=/home/user/go

/home/user/go/
    src/
        foo/
            bar/               (go code in package bar)
                x.go
            quux/              (go code in package main)
                y.go
    bin/
        quux                   (installed command)
    pkg/
        linux_amd64/
            foo/
                bar.a          (installed package object)

..........

if GOPATH has been set to Base Project DIR and still has this problem, in windows you can try to set GOBIN as Base Project DIR\bin or %GOPATH%\bin.

fetch gives an empty response body

fetch("http://localhost:8988/api", {
    method: "GET",
    headers: {
       "Content-Type": "application/json"
    }
})
.then((response) =>response.json());
.then((data) => {
    console.log(data);
})
.catch(error => {
    return error;
});

Begin, Rescue and Ensure in Ruby?

This is why we need ensure:

def hoge
  begin
    raise
  rescue  
    raise # raise again
  ensure  
    puts 'ensure' # will be executed
  end  
  puts 'end of func' # never be executed
end  

Simple linked list in C++

I think that, to make sure the indeep linkage of each node in the list, the addNode method must be like this:

void addNode(struct node *head, int n) {
  if (head->Next == NULL) {
    struct node *NewNode = new node;
    NewNode->value = n;
    NewNode->Next = NULL;
    head->Next = NewNode;
  }
  else 
    addNode(head->Next, n);
}

Chrome says my extension's manifest file is missing or unreadable

If you are downloading samples from developer.chrome.com its possible that your actual folder is contained in a folder with the same name and this is creating a problem. For example your extracted sample extension named tabCapture will lool like this:

C:\Users\...\tabCapture\tabCapture

Commenting code in Notepad++

for .sql files Ctrl+K or Ctrl+Q does not work.

to insert comments in .sql files in Notepad++ try Ctrl+Shift+Q

(there is no shortcut to uncomment the code block though. I have tried that on v5.8.2 )

flutter corner radius with transparent background

Use transparent background color for the modalbottomsheet and give separate color for box decoration


   showModalBottomSheet(
      backgroundColor: Colors.transparent,
      context: context, builder: (context) {
    return Container(

      decoration: BoxDecoration(
        color: Colors.white,
        borderRadius: BorderRadius.only(
            topLeft:Radius.circular(40) ,
            topRight: Radius.circular(40)
        ),
      ),
      padding: EdgeInsets.symmetric(vertical: 20,horizontal: 60),
      child: Settings_Form(),
    );
  });

How to find all the subclasses of a class given its name?

The simplest solution in general form:

def get_subclasses(cls):
    for subclass in cls.__subclasses__():
        yield from get_subclasses(subclass)
        yield subclass

And a classmethod in case you have a single class where you inherit from:

@classmethod
def get_subclasses(cls):
    for subclass in cls.__subclasses__():
        yield from subclass.get_subclasses()
        yield subclass

How to sort an array of objects by multiple fields?

Here's a generic multidimensional sort, allowing for reversing and/or mapping on each level.

Written in Typescript. For Javascript, check out this JSFiddle

The Code

type itemMap = (n: any) => any;

interface SortConfig<T> {
  key: keyof T;
  reverse?: boolean;
  map?: itemMap;
}

export function byObjectValues<T extends object>(keys: ((keyof T) | SortConfig<T>)[]): (a: T, b: T) => 0 | 1 | -1 {
  return function(a: T, b: T) {
    const firstKey: keyof T | SortConfig<T> = keys[0];
    const isSimple = typeof firstKey === 'string';
    const key: keyof T = isSimple ? (firstKey as keyof T) : (firstKey as SortConfig<T>).key;
    const reverse: boolean = isSimple ? false : !!(firstKey as SortConfig<T>).reverse;
    const map: itemMap | null = isSimple ? null : (firstKey as SortConfig<T>).map || null;

    const valA = map ? map(a[key]) : a[key];
    const valB = map ? map(b[key]) : b[key];
    if (valA === valB) {
      if (keys.length === 1) {
        return 0;
      }
      return byObjectValues<T>(keys.slice(1))(a, b);
    }
    if (reverse) {
      return valA > valB ? -1 : 1;
    }
    return valA > valB ? 1 : -1;
  };
}

Usage Examples

Sorting a people array by last name, then first name:

interface Person {
  firstName: string;
  lastName: string;
}

people.sort(byObjectValues<Person>(['lastName','firstName']));

Sort language codes by their name, not their language code (see map), then by descending version (see reverse).

interface Language {
  code: string;
  version: number;
}

// languageCodeToName(code) is defined elsewhere in code

languageCodes.sort(byObjectValues<Language>([
  {
    key: 'code',
    map(code:string) => languageCodeToName(code),
  },
  {
    key: 'version',
    reverse: true,
  }
]));

MySQL - ERROR 1045 - Access denied

I could not connect to MySql Administrator. I fixed it by creating another user and assigning all the permissions.

I logged in with that new user and it worked.

Warning: push.default is unset; its implicit value is changing in Git 2.0

I was wondering why I was getting that big warning message on Ubuntu 16.04 (which comes with Git 2.7.4), but not on Arch Linux. The reason is that the warning was removed in Git 2.8 (March 2016):

Across the transition at around Git version 2.0, the user used to get a pretty loud warning when running "git push" without setting push.default configuration variable. We no longer warn because the transition was completed a long time ago.

So you won't see the warning if you have Git 2.8 and later and don't need to set push.default unless you want to change the default 'simple' behavior.

Update query PHP MySQL

Here i updated two variables and present date and time

$id = "1";
$title = "phpmyadmin";

 $sql=  mysql_query("UPDATE table_name SET id ='".$id."', title = '".$title."',now() WHERE id = '".$id."' ");

now() function update current date and time.

note: For update query we have define the particular id otherwise it update whole table defaulty

Use multiple custom fonts using @font-face?

You can use multiple font faces quite easily. Below is an example of how I used it in the past:

<!--[if (IE)]><!-->
    <style type="text/css" media="screen">
        @font-face {
            font-family: "Century Schoolbook";
            src: url(/fonts/century-schoolbook.eot);
        }
        @font-face {
            font-family: "Chalkduster";
            src: url(/fonts/chalkduster.eot);
        }
    </style>
<!--<![endif]-->
<!--[if !(IE)]><!-->
    <style type="text/css" media="screen">
        @font-face {
            font-family: "Century Schoolbook";
            src: url(/fonts/century-schoolbook.ttf);
        }
        @font-face {
            font-family: "Chalkduster";
            src: url(/fonts/chalkduster.ttf);
        }
    </style>
<!--<![endif]-->

It is worth noting that fonts can be funny across different Browsers. Font face on earlier browsers works, but you need to use eot files instead of ttf.

That is why I include my fonts in the head of the html file as I can then use conditional IE tags to use eot or ttf files accordingly.

If you need to convert ttf to eot for this purpose there is a brilliant website you can do this for free online, which can be found at http://ttf2eot.sebastiankippe.com/.

Hope that helps.

Using Git with Visual Studio

Visual Studio 2013 natively supports Git.

See the official announcement.

What is the easiest/best/most correct way to iterate through the characters of a string in Java?

I agree that StringTokenizer is overkill here. Actually I tried out the suggestions above and took the time.

My test was fairly simple: create a StringBuilder with about a million characters, convert it to a String, and traverse each of them with charAt() / after converting to a char array / with a CharacterIterator a thousand times (of course making sure to do something on the string so the compiler can't optimize away the whole loop :-) ).

The result on my 2.6 GHz Powerbook (that's a mac :-) ) and JDK 1.5:

  • Test 1: charAt + String --> 3138msec
  • Test 2: String converted to array --> 9568msec
  • Test 3: StringBuilder charAt --> 3536msec
  • Test 4: CharacterIterator and String --> 12151msec

As the results are significantly different, the most straightforward way also seems to be the fastest one. Interestingly, charAt() of a StringBuilder seems to be slightly slower than the one of String.

BTW I suggest not to use CharacterIterator as I consider its abuse of the '\uFFFF' character as "end of iteration" a really awful hack. In big projects there's always two guys that use the same kind of hack for two different purposes and the code crashes really mysteriously.

Here's one of the tests:

    int count = 1000;
    ...

    System.out.println("Test 1: charAt + String");
    long t = System.currentTimeMillis();
    int sum=0;
    for (int i=0; i<count; i++) {
        int len = str.length();
        for (int j=0; j<len; j++) {
            if (str.charAt(j) == 'b')
                sum = sum + 1;
        }
    }
    t = System.currentTimeMillis()-t;
    System.out.println("result: "+ sum + " after " + t + "msec");

CSS values using HTML5 data attribute

You can create with javascript some css-rules, which you can later use in your styles: http://jsfiddle.net/ARTsinn/vKbda/

var addRule = (function (sheet) {
    if(!sheet) return;
    return function (selector, styles) {
        if (sheet.insertRule) return sheet.insertRule(selector + " {" + styles + "}", sheet.cssRules.length);
        if (sheet.addRule) return sheet.addRule(selector, styles);
    }
}(document.styleSheets[document.styleSheets.length - 1]));

var i = 101;
while (i--) {
    addRule("[data-width='" + i + "%']", "width:" + i + "%");
}

This creates 100 pseudo-selectors like this:

[data-width='1%'] { width: 1%; }
[data-width='2%'] { width: 2%; }
[data-width='3%'] { width: 3%; }
...
[data-width='100%'] { width: 100%; }

Note: This is a bit offtopic, and not really what you (or someone) wants, but maybe helpful.

How do I completely rename an Xcode project (i.e. inclusive of folders)?

XCode 11.0+.

It's really simple now. Just go to Project Navigator left panel of the XCode window.
Press Enter to make it active for rename, just like you change the folder name.
enter image description here

Just change the new name here, and XCode will ask you for renaming other pieces of stuff.

enter image description here.

Tap on Rename here and you are done.
If you are confused about your root folder name that why it's not changed, well it's just a folder. just renamed it with a new name.
enter image description here

Rearrange columns using cut

using just the shell,

while read -r col1 col2
do
  echo $col2 $col1
done <"file"

The point of test %eax %eax

test is a non-destructive and, it doesn't return the result of the operation but it sets the flags register accordingly. To know what it really tests for you need to check the following instruction(s). Often out is used to check a register against 0, possibly coupled with a jz conditional jump.

Count a list of cells with the same background color

Excel has no way of gathering that attribute with it's built-in functions. If you're willing to use some VB, all your color-related questions are answered here:

http://www.cpearson.com/excel/colors.aspx

Example form the site:

The SumColor function is a color-based analog of both the SUM and SUMIF function. It allows you to specify separate ranges for the range whose color indexes are to be examined and the range of cells whose values are to be summed. If these two ranges are the same, the function sums the cells whose color matches the specified value. For example, the following formula sums the values in B11:B17 whose fill color is red.

=SUMCOLOR(B11:B17,B11:B17,3,FALSE)

Virtualhost For Wildcard Subdomain and Static Subdomain

This also works for https needed a solution to making project directories this was it. because chrome doesn't like non ssl anymore used free ssl. Notice: My Web Server is Wamp64 on Windows 10 so I wouldn't use this config because of variables unless your using wamp.

<VirtualHost *:443>
ServerAdmin [email protected]
ServerName test.com
ServerAlias *.test.com

SSLEngine On
SSLCertificateFile "conf/key/certificatecom.crt"
SSLCertificateKeyFile "conf/key/privatecom.key"

VirtualDocumentRoot "${INSTALL_DIR}/www/subdomains/%1/"

DocumentRoot "${INSTALL_DIR}/www/subdomains"
<Directory "${INSTALL_DIR}/www/subdomains/">
    Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require all granted
</Directory>

Is there a function to make a copy of a PHP array to another?

$arr_one_copy = array_combine(array_keys($arr_one), $arr_one);

Just to post one more solution ;)

How to use filter, map, and reduce in Python 3

Lambda

Try to understand the difference between a normal def defined function and lambda function. This is a program that returns the cube of a given value:

# Python code to illustrate cube of a number 
# showing difference between def() and lambda(). 
def cube(y): 
    return y*y*y 
  
lambda_cube = lambda y: y*y*y 
  
# using the normally 
# defined function 
print(cube(5)) 
  
# using the lamda function 
print(lambda_cube(5)) 

output:

125
125

Without using Lambda:

  • Here, both of them return the cube of a given number. But, while using def, we needed to define a function with a name cube and needed to pass a value to it. After execution, we also needed to return the result from where the function was called using the return keyword.

Using Lambda:

  • Lambda definition does not include a “return” statement, it always contains an expression that is returned. We can also put a lambda definition anywhere a function is expected, and we don’t have to assign it to a variable at all. This is the simplicity of lambda functions.

Lambda functions can be used along with built-in functions like filter(), map() and reduce().

lambda() with filter()

The filter() function in Python takes in a function and a list as arguments. This offers an elegant way to filter out all the elements of a sequence “sequence”, for which the function returns True.

my_list = [1, 5, 4, 6, 8, 11, 3, 12]

new_list = list(filter(lambda x: (x%2 == 0) , my_list))

print(new_list)


ages = [13, 90, 17, 59, 21, 60, 5]

adults = list(filter(lambda age: age>18, ages)) 
  
print(adults) # above 18 yrs 

output:

[4, 6, 8, 12]
[90, 59, 21, 60]

lambda() with map()

The map() function in Python takes in a function and a list as an argument. The function is called with a lambda function and a list and a new list is returned which contains all the lambda modified items returned by that function for each item.

my_list = [1, 5, 4, 6, 8, 11, 3, 12]

new_list = list(map(lambda x: x * 2 , my_list))

print(new_list)


cities = ['novi sad', 'ljubljana', 'london', 'new york', 'paris'] 
  
# change all city names 
# to upper case and return the same 
uppered_cities = list(map(lambda city: str.upper(city), cities)) 
  
print(uppered_cities)

output:

[2, 10, 8, 12, 16, 22, 6, 24]
['NOVI SAD', 'LJUBLJANA', 'LONDON', 'NEW YORK', 'PARIS']

reduce

reduce() works differently than map() and filter(). It does not return a new list based on the function and iterable we've passed. Instead, it returns a single value.

Also, in Python 3 reduce() isn't a built-in function anymore, and it can be found in the functools module.

The syntax is:

reduce(function, sequence[, initial])

reduce() works by calling the function we passed for the first two items in the sequence. The result returned by the function is used in another call to function alongside with the next (third in this case), element.

The optional argument initial is used, when present, at the beginning of this "loop" with the first element in the first call to function. In a way, the initial element is the 0th element, before the first one, when provided.

lambda() with reduce()

The reduce() function in Python takes in a function and a list as an argument. The function is called with a lambda function and an iterable and a new reduced result is returned. This performs a repetitive operation over the pairs of the iterable.

from functools import reduce

my_list = [1, 1, 2, 3, 5, 8, 13, 21, 34] 

sum = reduce((lambda x, y: x + y), my_list) 

print(sum) # sum of a list
print("With an initial value: " + str(reduce(lambda x, y: x + y, my_list, 100)))
88
With an initial value: 188

These functions are convenience functions. They are there so you can avoid writing more cumbersome code, but avoid using both them and lambda expressions too much, because "you can", as it can often lead to illegible code that's hard to maintain. Use them only when it's absolutely clear what's going on as soon as you look at the function or lambda expression.

CSS: Set a background color which is 50% of the width of the window

Simple solution to achieve "split in two" background:

background: linear-gradient(to left, #ff0000 50%, #0000ff 50%);

You can also use degrees as direction

background: linear-gradient(80deg, #ff0000 50%, #0000ff 50%);

jquery $.each() for objects

$.each() works for objects and arrays both:

var data = { "programs": [ { "name":"zonealarm", "price":"500" }, { "name":"kaspersky", "price":"200" } ] };

$.each(data.programs, function (i) {
    $.each(data.programs[i], function (key, val) {
        alert(key + val);
    });
});

...and since you will get the current array element as second argument:

$.each(data.programs, function (i, currProgram) {
    $.each(currProgram, function (key, val) {
        alert(key + val);
    });
});

How to check sbt version?

Running the command, "sbt sbt-version" will simply output your current directory and the version number.

$ sbt sbt-version
[info] Set current project to spark (in build file:/home/morgan/code/spark/)
[info] 0.13.8

javascript onclick increment number

var i=0; 
function increment() {           
    i++;       
    document.getElementById('number').innerHTML=i;
}

Composer: The requested PHP extension ext-intl * is missing from your system

I have solved this problem by adding --ignore-platform-reqs command with composer install in ubuntu.

composer install --ignore-platform-reqs

Get element type with jQuery

you can use .is():

  $( "ul" ).click(function( event ) {
      var target = $( event.target );
      if ( target.is( "li" ) ) {
         target.css( "background-color", "red" );
      }
  });

see source

How do you round a double in Dart to a given degree of precision AFTER the decimal point?

num.toStringAsFixed() rounds. This one turns you num (n) into a string with the number of decimals you want (2), and then parses it back to your num in one sweet line of code:

n = num.parse(n.toStringAsFixed(2));

Can someone explain how to implement the jQuery File Upload plugin?

Check out the Image drag and drop uploader with image preview using dropper jquery plugin.

HTML

<div class="target" width="78" height="100"><img /></div>

JS

$(".target").dropper({
    action: "upload.php",

}).on("start.dropper", onStart);
function onStart(e, files){
console.log(files[0]);

    image_preview(files[0].file).then(function(res){
$('.dropper-dropzone').empty();
//$('.dropper-dropzone').css("background-image",res.data);
 $('#imgPreview').remove();        
$('.dropper-dropzone').append('<img id="imgPreview"/><span style="display:none">Drag and drop files or click to select</span>');
var widthImg=$('.dropper-dropzone').attr('width');
        $('#imgPreview').attr({width:widthImg});
    $('#imgPreview').attr({src:res.data});

    })

}

function image_preview(file){
    var def = new $.Deferred();
    var imgURL = '';
    if (file.type.match('image.*')) {
        //create object url support
        var URL = window.URL || window.webkitURL;
        if (URL !== undefined) {
            imgURL = URL.createObjectURL(file);
            URL.revokeObjectURL(file);
            def.resolve({status: 200, message: 'OK', data:imgURL, error: {}});
        }
        //file reader support
        else if(window.File && window.FileReader)
        {
            var reader = new FileReader();
            reader.readAsDataURL(file);
            reader.onloadend = function () {
                imgURL = reader.result;
                def.resolve({status: 200, message: 'OK', data:imgURL, error: {}});
            }
        }
        else {
            def.reject({status: 1001, message: 'File uploader not supported', data:imgURL, error: {}});
        }
    }
    else
        def.reject({status: 1002, message: 'File type not supported', error: {}});
    return def.promise();
}

$('.dropper-dropzone').mouseenter(function() {
 $( '.dropper-dropzone>span' ).css("display", "block");
});

$('.dropper-dropzone').mouseleave(function() {
 $( '.dropper-dropzone>span' ).css("display", "none");
});

CSS

.dropper-dropzone{
    width:78px;
padding:3px;
    height:100px;
position: relative;
}
.dropper-dropzone>img{
    width:78px;
    height:100px;
margin-top=0;
}

.dropper-dropzone>span {
    position: absolute;
    right: 10px;
    top: 20px;
color:#ccc;


}

.dropper .dropper-dropzone{

padding:3px !important    
}

Demo Jsfiddle

JavaScript/jQuery - How to check if a string contain specific words

This will

/\bword\b/.test("Thisword is not valid");

return false, when this one

/\bword\b/.test("This word is valid");

will return true.

Mergesort with Python

A longer one that counts inversions and adheres to the sorted interface. It's trivial to modify this to make it a method of an object that sorts in place.

import operator

class MergeSorted:

    def __init__(self):
        self.inversions = 0

    def __call__(self, l, key=None, reverse=False):

        self.inversions = 0

        if key is None:
            self.key = lambda x: x
        else:
            self.key = key

        if reverse:
            self.compare = operator.gt
        else:
            self.compare = operator.lt

        dest = list(l)
        working = [0] * len(l)
        self.inversions = self._merge_sort(dest, working, 0, len(dest))
        return dest

    def _merge_sort(self, dest, working, low, high):
        if low < high - 1:
            mid = (low + high) // 2
            x = self._merge_sort(dest, working, low, mid)
            y = self._merge_sort(dest, working, mid, high)
            z = self._merge(dest, working, low, mid, high)
            return (x + y + z)
        else:
            return 0

    def _merge(self, dest, working, low, mid, high):
        i = 0
        j = 0
        inversions = 0

        while (low + i < mid) and (mid + j < high):
            if self.compare(self.key(dest[low + i]), self.key(dest[mid + j])):
                working[low + i + j] = dest[low + i]
                i += 1
            else:
                working[low + i + j] = dest[mid + j]
                inversions += (mid - (low + i))
                j += 1

        while low + i < mid:
            working[low + i + j] = dest[low + i]
            i += 1

        while mid + j < high:
            working[low + i + j] = dest[mid + j]
            j += 1

        for k in range(low, high):
            dest[k] = working[k]

        return inversions


msorted = MergeSorted()

Uses

>>> l = [5, 2, 3, 1, 4]
>>> s = msorted(l)
>>> s
[1, 2, 3, 4, 5]
>>> msorted.inversions
6

>>> l = ['e', 'b', 'c', 'a', 'd']
>>> d = {'a': 10,
...      'b': 4,
...      'c': 2,
...      'd': 5,
...      'e': 9}
>>> key = lambda x: d[x]
>>> s = msorted(l, key=key)
>>> s
['c', 'b', 'd', 'e', 'a']
>>> msorted.inversions
5

>>> l = [5, 2, 3, 1, 4]
>>> s = msorted(l, reverse=True)
>>> s
[5, 4, 3, 2, 1]
>>> msorted.inversions
4

>>> l = ['e', 'b', 'c', 'a', 'd']
>>> d = {'a': 10,
...      'b': 4,
...      'c': 2,
...      'd': 5,
...      'e': 9}
>>> key = lambda x: d[x]
>>> s = msorted(l, key=key, reverse=True)
>>> s
['a', 'e', 'd', 'b', 'c']
>>> msorted.inversions
5

Load Image from javascript

If you are loading the image via AJAX you could use a callback to check if the image is loaded and do the hiding and src attribute assigning. Something like this:

$.ajax({ 
  url: [image source],
  success: function() {
  // Do the hiding here and the attribute setting
  }
});

For more reading refer to this JQuery AJAX

Why does only the first line of this Windows batch file execute but all three lines execute in a command shell?

To execute more Maven builds from one script you shall use the Windows call function in the following way:

call mvn install:install-file -DgroupId=gdata -DartifactId=base -Dversion=1.0 -Dfile=gdata-base-1.0.jar  -Dpackaging=jar -DgeneratePom=true
call mvn install:install-file -DgroupId=gdata -DartifactId=blogger -Dversion=2.0 -Dfile=gdata-blogger-2.0.jar  -Dpackaging=jar -DgeneratePom=true
call mvn install:install-file -DgroupId=gdata -DartifactId=blogger-meta -Dversion=2.0 -Dfile=gdata-blogger-meta-2.0.jar  -Dpackaging=jar -DgeneratePom=true

How to pull remote branch from somebody else's repo

If the forked repo is protected so you can't push directly into it, and your goal is to make changes to their foo, then you need to get their branch foo into your repo like so:

git remote add protected_repo https://github.com/theirusername/their_repo.git
git fetch protected_repo 
git checkout --no-track protected_repo/foo

Now you have a local copy of foo with no upstream associated to it. You can commit changes to it (or not) and then push your foo to your own remote repo.

git push --set-upstream origin foo

Now foo is in your repo on GitHub and your local foo is tracking it. If they continue to make changes to foo you can fetch theirs and merge into your foo.

git checkout foo 
git fetch protected_repo
git merge protected_repo/foo

How to return dictionary keys as a list in Python?

Try list(newdict.keys()).

This will convert the dict_keys object to a list.

On the other hand, you should ask yourself whether or not it matters. The Pythonic way to code is to assume duck typing (if it looks like a duck and it quacks like a duck, it's a duck). The dict_keys object will act like a list for most purposes. For instance:

for key in newdict.keys():
  print(key)

Obviously, insertion operators may not work, but that doesn't make much sense for a list of dictionary keys anyway.

int to string in MySQL

You could use CONCAT, and the numeric argument of it is converted to its equivalent binary string form.

select t2.* 
from t1 join t2 
on t2.url=CONCAT('site.com/path/%', t1.id, '%/more') where t1.id > 9000

Troubleshooting "Illegal mix of collations" error in mysql

Solution if literals are involved.

I am using Pentaho Data Integration and dont get to specify the sql syntax. Using a very simple DB lookup gave the error "Illegal mix of collations (cp850_general_ci,COERCIBLE) and (latin1_swedish_ci,COERCIBLE) for operation '='"

The generated code was "SELECT DATA_DATE AS latest_DATA_DATE FROM hr_cc_normalised_data_date_v WHERE PSEUDO_KEY = ?"

Cutting the story short the lookup was to a view and when I issued

mysql> show full columns from hr_cc_normalised_data_date_v;
+------------+------------+-------------------+------+-----+
| Field      | Type       | Collation         | Null | Key |
+------------+------------+-------------------+------+-----+
| PSEUDO_KEY | varchar(1) | cp850_general_ci  | NO   |     |
| DATA_DATE  | varchar(8) | latin1_general_cs | YES  |     |
+------------+------------+-------------------+------+-----+

which explains where the 'cp850_general_ci' comes from.

The view was simply created with 'SELECT 'X',......' According to the manual literals like this should inherit their character set and collation from server settings which were correctly defined as 'latin1' and 'latin1_general_cs' as this clearly did not happen I forced it in the creation of the view

CREATE OR REPLACE VIEW hr_cc_normalised_data_date_v AS
SELECT convert('X' using latin1) COLLATE latin1_general_cs        AS PSEUDO_KEY
    ,  DATA_DATE
FROM HR_COSTCENTRE_NORMALISED_mV
LIMIT 1;

now it shows latin1_general_cs for both columns and the error has gone away. :)

$apply already in progress error

I call $scope.$apply like this to ignored call multiple in one times.

      var callApplyTimeout = null;
      function callApply(callback) {
          if (!callback) callback = function () { };
          if (callApplyTimeout) $timeout.cancel(callApplyTimeout);

          callApplyTimeout = $timeout(function () {
              callback();
              $scope.$apply();
              var d = new Date();
              var m = d.getMilliseconds();
              console.log('$scope.$apply(); call ' + d.toString() + ' ' + m);
          }, 300);
      }

simply call

callApply();

Laravel 5 – Remove Public from URL

I have solved the issue using 2 answers:

  1. Renaming the server.php to index.php (no modifications)
  2. Copy the .htaccess from public folder to root folder (like rimon.ekjon said below)
  3. Changing .htaccess it a bit as follows for statics:

    RewriteEngine On
    
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule ^(.*)/$ /$1 [L,R=301]
    
    RewriteCond %{REQUEST_URI} !(\.css|\.js|\.png|\.jpg|\.gif|robots\.txt)$ [NC]
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^ index.php [L]
    
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_URI} !^/public/
    RewriteRule ^(css|js|images)/(.*)$ public/$1/$2 [L,NC]
    

    If there are any other static files needed just add the extension to the previous declared list

How to disable or enable viewpager swiping in android

For disabling swiping

mViewPager.beginFakeDrag();

For enable swiping

if (mViewPager.isFakeDragging()) mViewPager.endFakeDrag();

Which is faster: multiple single INSERTs or one multiple-row INSERT?

A major factor will be whether you're using a transactional engine and whether you have autocommit on.

Autocommit is on by default and you probably want to leave it on; therefore, each insert that you do does its own transaction. This means that if you do one insert per row, you're going to be committing a transaction for each row.

Assuming a single thread, that means that the server needs to sync some data to disc for EVERY ROW. It needs to wait for the data to reach a persistent storage location (hopefully the battery-backed ram in your RAID controller). This is inherently rather slow and will probably become the limiting factor in these cases.

I'm of course assuming that you're using a transactional engine (usually innodb) AND that you haven't tweaked the settings to reduce durability.

I'm also assuming that you're using a single thread to do these inserts. Using multiple threads muddies things a bit because some versions of MySQL have working group-commit in innodb - this means that multiple threads doing their own commits can share a single write to the transaction log, which is good because it means fewer syncs to persistent storage.

On the other hand, the upshot is, that you REALLY WANT TO USE multi-row inserts.

There is a limit over which it gets counter-productive, but in most cases it's at least 10,000 rows. So if you batch them up to 1,000 rows, you're probably safe.

If you're using MyISAM, there's a whole other load of things, but I'll not bore you with those. Peace.

Make the size of a heatmap bigger with seaborn

You could alter the figsize by passing a tuple showing the width, height parameters you would like to keep.

import matplotlib.pyplot as plt

fig, ax = plt.subplots(figsize=(10,10))         # Sample figsize in inches
sns.heatmap(df1.iloc[:, 1:6:], annot=True, linewidths=.5, ax=ax)

EDIT

I remember answering a similar question of yours where you had to set the index as TIMESTAMP. So, you could then do something like below:

df = df.set_index('TIMESTAMP')
df.resample('30min').mean()
fig, ax = plt.subplots()
ax = sns.heatmap(df.iloc[:, 1:6:], annot=True, linewidths=.5)
ax.set_yticklabels([i.strftime("%Y-%m-%d %H:%M:%S") for i in df.index], rotation=0)

For the head of the dataframe you posted, the plot would look like:

enter image description here

How do I create a timeline chart which shows multiple events? Eg. Metallica Band members timeline on wiki

A Stacked bar chart should suffice:

Setup data as follows

Name    Start       End         Duration (End - Start)
Fred    1/01/1981   1/06/1985    1612   
Bill    1/07/1985   1/11/2000    5602  
Joe     1/01/1980   1/12/2001    8005  
Jim     1/03/1999   1/01/2000    306  
  1. Plot Start and Duration as a stacked bar chart
  2. Set the X-Axis minimum to the desired start date
  3. Set the Fill Colour of thestart range to no fill
  4. Set the Fill of individual bars to suit

(example prepared in Excel 2010)

enter image description here

AngularJS: ng-model not binding to ng-checked for checkboxes

ngModel and ngChecked are not meant to be used together.

ngChecked is expecting an expression, so by saying ng-checked="true", you're basically saying that the checkbox will always be checked by default.

You should be able to just use ngModel, tied to a boolean property on your model. If you want something else, then you either need to use ngTrueValue and ngFalseValue (which only support strings right now), or write your own directive.

What is it exactly that you're trying to do? If you just want the first checkbox to be checked by default, you should change your model -- item1: true,.

Edit: You don't have to submit your form to debug the current state of the model, btw, you can just dump {{testModel}} into your HTML (or <pre>{{testModel|json}}</pre>). Also your ngModel attributes can be simplified to ng-model="testModel.item1".

http://plnkr.co/edit/HtdOok8aieBjT5GFZOb3?p=preview

How to execute Table valued function

A TVF (table-valued function) is supposed to be SELECTed FROM. Try this:

select * from FN('myFunc')

Where is HttpContent.ReadAsAsync?

I have the same problem, so I simply get JSON string and deserialize to my class:

HttpResponseMessage response = await client.GetAsync("Products");
//get data as Json string 
string data = await response.Content.ReadAsStringAsync();
//use JavaScriptSerializer from System.Web.Script.Serialization
JavaScriptSerializer JSserializer = new JavaScriptSerializer();
//deserialize to your class
products = JSserializer.Deserialize<List<Product>>(data);

Enable binary mode while restoring a Database from an SQL dump

The file you are trying to import is a zip file. Unzip the file and then try to import again.

Dealing with "java.lang.OutOfMemoryError: PermGen space" error

The only way that worked for me was with the JRockit JVM. I have MyEclipse 8.6.

The JVM's heap stores all the objects generated by a running Java program. Java uses the new operator to create objects, and memory for new objects is allocated on the heap at run time. Garbage collection is the mechanism of automatically freeing up the memory contained by the objects that are no longer referenced by the program.

Access item in a list of lists

50 - List1[0][0] + List[0][1] - List[0][2]

List[0] gives you the first list in the list (try out print List[0]). Then, you index into it again to get the items of that list. Think of it this way: (List1[0])[0].

Use different Python version with virtualenv

For Debian (debian 9) Systems in 2019, I discovered a simple solution that may solve the problem from within the virtual environment.

Suppose the virtual environment were created via:

python3.7 -m venv myenv

but only has versions of python2 and python2.7, and you need the recent features of python3.7.

Then, simply running the command:

(myvenv) $ python3.7 -m venv --upgrade /home/username/path/to/myvenv/

will add python3.7 packages if they are already available on your system.

How to use a SQL SELECT statement with Access VBA

Access 2007 can lose the CurrentDb: see http://support.microsoft.com/kb/167173, so in the event of getting "Object Invalid or no longer set" with the examples, use:

Dim db as Database
Dim rs As DAO.Recordset
Set db = CurrentDB
Set rs = db.OpenRecordset("SELECT * FROM myTable")

Convert array of strings into a string in Java

Following is an example of Array to String conversion.

    public class ArrayToString
    {
public static void main(String[] args) { String[] strArray = new String[]{"Java", "PHP", ".NET", "PERL", "C", "COBOL"};

        String newString = Arrays.toString(strArray);

        newString = newString.substring(1, newString.length()-1);

        System.out.println("New New String: " + newString);
    }
}

Exception of type 'System.OutOfMemoryException' was thrown. Why?

It runs successfully the first time, but if I run it again, I keep getting a System.OutOfMemoryException. What are some reasons this could be happening?

Regardless of what the others have said, the error has nothing to do with forgetting to dispose your DBCommand or DBConnection, and you will not fix your error by disposing of either of them.

The error has everything to do with your dataset which contains nearly 600,000 rows of data. Apparently your dataset consumes more than 50% of the available memory on your machine. Clearly, you'll run out of memory when you return another dataset of the same size before the first one has been garbage collected. Simple as that.

You can remedy this problem in a few ways:

  • Consider returning fewer records. I personally can't imagine a time when returning 600K records has ever been useful to a user. To minimize the records returned, try:

    • Limiting your query to the first 1000 records. If there are more than 1000 results returned from the query, inform the user to narrow their search results.

    • If your users really insist on seeing that much data at once, try paging the data. Remember: Google never shows you all 22 bajillion results of a search at once, it shows you 20 or so records at a time. Google probably doesn't hold all 22 bajillion results in memory at once, it probably finds its more memory efficient to requery its database to generate a new page.

  • If you just need to iterate through the data and you don't need random access, try returning a datareader instead. A datareader only loads one record into memory at a time.

If none of those are an option, then you need to force .NET to free up the memory used by the dataset before calling your method using one of these methods:

  • Remove all references to your old dataset. Anything holding on to a refenence of your dataset will prevent it from being reclaimed by memory.

  • If you can't null all the references to your dataset, clear all of the rows from the dataset and any objects bound to those rows instead. This removes references to the datarows and allows them to be eaten by the garbage collector.

I don't believe you'll need to call GC.Collect() to force a gen cycle. Not only is it generally a bad idea to call GC.Collect(), because sufficient memory pressure will cause .NET invoke the garbage collector on its own.

Note: calling Dispose on your dataset does not free any memory, nor does it invoke the garbage collector, nor does it remove a reference to your dataset. Dispose is used to clean up unmanaged resources, but the DataSet does not have any unmanaged resources. It only implements IDispoable because it inherents from MarshalByValueComponent, so the Dispose method on the dataset is pretty much useless.

How to see what privileges are granted to schema of another user

Login into the database. then run the below query

select * from dba_role_privs where grantee = 'SCHEMA_NAME';

All the role granted to the schema will be listed.

Thanks Szilagyi Donat for the answer. This one is taken from same and just where clause added.

How to find item with max value using linq?

With EF or LINQ to SQL:

var item = db.Items.OrderByDescending(i => i.Value).FirstOrDefault();

With LINQ to Objects I suggest to use morelinq extension MaxBy (get morelinq from nuget):

var item = items.MaxBy(i => i.Value);

nuget 'packages' element is not declared warning

This happens because VS doesn't know the schema of this file. Note that this file is more of an implementation detail, and not something you normally need to open directly. Instead, you can use the NuGet dialog to manage the packages installed in a project.

How do I get PHP errors to display?

If you somehow find yourself in a situation where you can't modifiy the setting via php.ini or .htaccess you're out of luck for displaying errors when your PHP scripts contain parse errors. You'd then have to resolve to linting the files on the command line like this:

find . -name '*.php' -type f -print0 | xargs -0 -n1 -P8 php -l | grep -v "No syntax errors"

If your host is so locked down that it does not allow changing the value via php.ini or .htaccess, it may also disallow changing the value via ini_set. You can check that with the following PHP script:

<?php
if( !ini_set( 'display_errors', 1 ) ) {
  echo "display_errors cannot be set.";
} else {
  echo "changing display_errors via script is possible.";
}

How do I alter the position of a column in a PostgreSQL database table?

I was working on re-ordering a lot of tables and didn't want to have to write the same queries over and over so I made a script to do it all for me. Essentially, it:

  1. Gets the table creation SQL from pg_dump
  2. Gets all available columns from the dump
  3. Puts the columns in the desired order
  4. Modifies the original pg_dump query to create a re-ordered table with data
  5. Drops old table
  6. Renames new table to match old table

It can be used by running the following simple command:

./reorder.py -n schema -d database table \
    first_col second_col ... penultimate_col ultimate_col --migrate

It prints out the sql so you can verify and test it, that was a big reason I based it on pg_dump. You can find the github repo here.

How can I fetch all items from a DynamoDB table without specifying the primary key?

This C# code is to fetch all items from a dynamodb table using BatchGet or CreateBatchGet

        string tablename = "AnyTableName"; //table whose data you want to fetch

        var BatchRead = ABCContext.Context.CreateBatchGet<ABCTable>(  

            new DynamoDBOperationConfig
            {
                OverrideTableName = tablename; 
            });

        foreach(string Id in IdList) // in case you are taking string from input
        {
            Guid objGuid = Guid.Parse(Id); //parsing string to guid
            BatchRead.AddKey(objGuid);
        }

        await BatchRead.ExecuteAsync();
        var result = BatchRead.Results;

// ABCTable is the table modal which is used to create in dynamodb & data you want to fetch

nginx showing blank PHP pages

I had a similar error , but in combination with Nextcloud. So in case this did not work, try: Having a look at the Nginx manual.

How do I get a list of locked users in an Oracle database?

Found it!

SELECT username, 
       account_status
  FROM dba_users;

jQuery - Getting the text value of a table cell in the same row as a clicked element

it should work fine:

var Something = $(this).children("td:nth-child(n)").text();

What techniques can be used to define a class in JavaScript, and what are their trade-offs?

The simple way is:

function Foo(a) {
  var that=this;

  function privateMethod() { .. }

  // public methods
  that.add = function(b) {
    return a + b;
  };
  that.avg = function(b) {
    return that.add(b) / 2; // calling another public method
  };
}

var x = new Foo(10);
alert(x.add(2)); // 12
alert(x.avg(20)); // 15

The reason for that is that this can be bound to something else if you give a method as an event handler, so you save the value during instantiation and use it later.

Edit: it's definitely not the best way, just a simple way. I'm waiting for good answers too!

Node.js - How to send data from html to express

I'd like to expand on Obertklep's answer. In his example it is an NPM module called body-parser which is doing most of the work. Where he puts req.body.name, I believe he/she is using body-parser to get the contents of the name attribute(s) received when the form is submitted.

If you do not want to use Express, use querystring which is a built-in Node module. See the answers in the link below for an example of how to use querystring.

It might help to look at this answer, which is very similar to your quest.

Maximum length for MySQL type text

Type       | Approx. Length     | Exact Max. Length Allowed
-----------------------------------------------------------
TINYTEXT   | 256 Bytes          |           255 characters
TEXT       |  64 Kilobytes      |        65,535 characters
MEDIUMTEXT |  16 Megabytes      |    16,777,215 characters
LONGTEXT   |   4 Gigabytes      | 4,294,967,295 characters

Basically, it's like:

"Exact Max. Length Allowed" = "Approx. Length" in bytes - 1

Note: If using multibyte characters (like Arabic, where each Arabic character takes 2 bytes), the column "Exact Max. Length Allowed" for TINYTEXT can hold be up to 127 Arabic characters (Note: space, dash, underscore, and other such characters, are 1-byte characters).

Guzzlehttp - How get the body of a response from Guzzle 6?

For get response in JSON format :

  1.$response = (string) $res->getBody();
      $response =json_decode($response); // Using this you can access any key like below
     
     $key_value = $response->key_name; //access key  

  2. $response = json_decode($res->getBody(),true);
     
     $key_value =   $response['key_name'];//access key

How to get file creation & modification date/times in Python?

You have a couple of choices. For one, you can use the os.path.getmtime and os.path.getctime functions:

import os.path, time
print("last modified: %s" % time.ctime(os.path.getmtime(file)))
print("created: %s" % time.ctime(os.path.getctime(file)))

Your other option is to use os.stat:

import os, time
(mode, ino, dev, nlink, uid, gid, size, atime, mtime, ctime) = os.stat(file)
print("last modified: %s" % time.ctime(mtime))

Note: ctime() does not refer to creation time on *nix systems, but rather the last time the inode data changed. (thanks to kojiro for making that fact more clear in the comments by providing a link to an interesting blog post)

No Such Element Exception?

I Know this question was aked 3 years ago, but I just had the same problem, and what solved it was instead of putting:

 while (i.hasNext()) {
    // code goes here 
}

I did one iteration at the start, and then checked for condition using:

do {
   // code goes here
} while (i.hasNext());

I hope this will help some people at some stage.

Apache error: _default_ virtualhost overlap on port 443

It is highly unlikely that adding NameVirtualHost *:443 is the right solution, because there are a limited number of situations in which it is possible to support name-based virtual hosts over SSL. Read this and this for some details (there may be better docs out there; these were just ones I found that discuss the issue in detail).

If you're running a relatively stock Apache configuration, you probably have this somewhere:

<VirtualHost _default_:443>

Your best bet is to either:

  • Place your additional SSL configuration into this existing VirtualHost container, or
  • Comment out this entire VirtualHost block and create a new one. Don't forget to include all the relevant SSL options.

How to get full path of selected file on change of <input type=‘file’> using javascript, jquery-ajax?

You can, if uploading an entire folder is an option for you

<input type="file" webkitdirectory directory multiple/>

change event will contain:

.target.files[...].webkitRelativePath: "FOLDER/FILE.ext"

How to call VS Code Editor from terminal / command line

In linux terminal you can just type:

$ code run

What is the difference between MOV and LEA?

The instruction MOV reg,addr means read a variable stored at address addr into register reg. The instruction LEA reg,addr means read the address (not the variable stored at the address) into register reg.

Another form of the MOV instruction is MOV reg,immdata which means read the immediate data (i.e. constant) immdata into register reg. Note that if the addr in LEA reg,addr is just a constant (i.e. a fixed offset) then that LEA instruction is essentially exactly the same as an equivalent MOV reg,immdata instruction that loads the same constant as immediate data.

Is there a GUI design app for the Tkinter / grid geometry?

Apart from the options already given in other answers, there's a current more active, recent and open-source project called pygubu.

This is the first description by the author taken from the github repository:

Pygubu is a RAD tool to enable quick & easy development of user interfaces for the python tkinter module.

The user interfaces designed are saved as XML, and by using the pygubu builder these can be loaded by applications dynamically as needed. Pygubu is inspired by Glade.


Pygubu hello world program is an introductory video explaining how to create a first project using Pygubu.

The following in an image of interface of the last version of pygubu designer on a OS X Yosemite 10.10.2:

enter image description here

I would definitely give it a try, and contribute to its development.

macOS on VMware doesn't recognize iOS device

I had the same issue, but was quite easy to solve. Follow the next steps:

1) In the Virtual Machine (VMWare) settings:

  • Set the USB compatibility to be 2.0 instead of 3.0
  • Check the setting "Show all USB input devices"

2) Add the device into the list of allowed development devices in your Apple Developer's account. Without that step there is no way to use your device in Xcode.

Next some instructions: Register a single device

PowerShell: Format-Table without headers

Here is how I solve this. I just pipe the output to Out-String and then pass that output to the .NET Trim function:

(gci | ft -HideTableHeaders | Out-String).Trim()

This will strip out the line breaks before and after the table.

You can also use TrimStart to just take care of the header's line break if you still want the trailing line breaks.

(gci | ft -HideTableHeaders | Out-String).TrimStart()

Execute a shell script in current shell with sudo permission

I'm not sure if this breaks any rules but

sudo bash script.sh

seems to work for me.

Failed to connect to mailserver at "localhost" port 25

Change SMTP=localhost to SMTP=smtp.gmail.com

Gunicorn worker timeout error

Frank's answer pointed me in the right direction. I have a Digital Ocean droplet accessing a managed Digital Ocean Postgresql database. All I needed to do was add my droplet to the database's "Trusted Sources".

(click on database in DO console, then click on settings. Edit Trusted Sources and select droplet name (click in editable area and it will be suggested to you)).

Python's most efficient way to choose longest string in list?

len(each) == max(len(x) for x in myList) or just each == max(myList, key=len)

How to search file text for a pattern and replace it with a given value

Here an alternative to the one liner from jim, this time in a script

ARGV[0..-3].each{|f| File.write(f, File.read(f).gsub(ARGV[-2],ARGV[-1]))}

Save it in a script, eg replace.rb

You start in on the command line with

replace.rb *.txt <string_to_replace> <replacement>

*.txt can be replaced with another selection or with some filenames or paths

broken down so that I can explain what's happening but still executable

# ARGV is an array of the arguments passed to the script.
ARGV[0..-3].each do |f| # enumerate the arguments of this script from the first to the last (-1) minus 2
  File.write(f,  # open the argument (= filename) for writing
    File.read(f) # open the argument (= filename) for reading
    .gsub(ARGV[-2],ARGV[-1])) # and replace all occurances of the beforelast with the last argument (string)
end

EDIT: if you want to use a regular expression use this instead Obviously, this is only for handling relatively small text files, no Gigabyte monsters

ARGV[0..-3].each{|f| File.write(f, File.read(f).gsub(/#{ARGV[-2]}/,ARGV[-1]))}

How to set a CheckBox by default Checked in ASP.Net MVC

My way is @Html.CheckBoxFor(model => model.As, new { @value= "true" }) (meaning is checked)

Run Command Line & Command From VBS

Set oShell = CreateObject ("WScript.Shell") 
oShell.run "cmd.exe /C copy ""S:Claims\Sound.wav"" ""C:\WINDOWS\Media\Sound.wav"" "

Javascript replace with reference to matched group?

For the replacement string and the replacement pattern as specified by $. here a resume:

enter image description here

link to doc : here

"hello _there_".replace(/_(.*?)_/g, "<div>$1</div>")



Note:

If you want to have a $ in the replacement string use $$. Same as with vscode snippet system.

Change input value onclick button - pure javascript or jQuery

Try This(Simple javascript):-

_x000D_
_x000D_
 <!DOCTYPE html>_x000D_
    <html>_x000D_
       <script>_x000D_
          function change(value){_x000D_
          document.getElementById("count").value= 500*value;_x000D_
          document.getElementById("totalValue").innerHTML= "Total price: $" + 500*value;_x000D_
          }_x000D_
          _x000D_
       </script>_x000D_
       <body>_x000D_
          Product price: $500_x000D_
          <br>_x000D_
          <div id= "totalValue">Total price: $500 </div>_x000D_
          <br>_x000D_
          <input type="button" onclick="change(2)" value="2&#x00A;Qty">_x000D_
          <input type="button" onclick="change(4)" value="4&#x00A;Qty">_x000D_
          <br>_x000D_
          Total <input type="text" id="count" value="1">_x000D_
       </body>_x000D_
    </html>
_x000D_
_x000D_
_x000D_

Hope this will help you..

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

I ran into this recently. It turned out that the old DLL was compiled with a previous version (Visual Studio 2008) and was referencing that version of the dynamic runtime libraries. I was trying to run it on a system that only had .NET 4.0 on it and I'd never installed any dynamic runtime libraries. The solution? I recompiled the DLL to link the static runtime libraries.

Check your application error log in Event Viewer (EVENTVWR.EXE). It will give you more information on the error and will probably point you at the real cause of the problem.

Select Rows with id having even number

Try this:

SELECT DISTINCT city FROM STATION WHERE ID%2=0 ORDER BY CITY;

Find object in list that has attribute equal to some value (that meets any condition)

next((x for x in test_list if x.value == value), None)

This gets the first item from the list that matches the condition, and returns None if no item matches. It's my preferred single-expression form.

However,

for x in test_list:
    if x.value == value:
        print("i found it!")
        break

The naive loop-break version, is perfectly Pythonic -- it's concise, clear, and efficient. To make it match the behavior of the one-liner:

for x in test_list:
    if x.value == value:
        print("i found it!")
        break
else:
    x = None

This will assign None to x if you don't break out of the loop.

Subtract one day from datetime

You can try this.

Timestamp=2008-11-11 13:23:44.657;

SELECT DATE_SUB(OrderDate,INTERVAL 1 DAY) AS SubtractDate FROM Orders

output :2008-11-10 13:23:44.657

I hope, it will help to solve your problem.

java.lang.NoClassDefFoundError: org/apache/http/client/HttpClient

What could be the possible cause of this exception?

You may not have appropriate Jar in your class path.

How it could be removed?

By putting HTTPClient jar in your class path. If it's a webapp, copy Jar into WEB-INF/lib if it's standalone, make sure you have this jar in class path or explicitly set using -cp option

as the doc says,

Thrown if the Java Virtual Machine or a ClassLoader instance tries to load in the definition of a class (as part of a normal method call or as part of creating a new instance using the new expression) and no definition of the class could be found.

The searched-for class definition existed when the currently executing class was compiled, but the definition can no longer be found.

Edit:
If you are using a dependency management like Maven/Gradle (see the answer below) or SBT please use it to bring the httpclient jar for you.

the easiest way to convert matrix to one row vector

You can use the function RESHAPE:

B = reshape(A.',1,[]);

How to do something before on submit?

Assuming you have a form like this:

<form id="myForm" action="foo.php" method="post">
   <input type="text" value="" />
   <input type="submit" value="submit form" />

</form>

You can attach a onsubmit-event with jQuery like this:

$('#myForm').submit(function() {
  alert('Handler for .submit() called.');
  return false;
});

If you return false the form won't be submitted after the function, if you return true or nothing it will submit as usual.

See the jQuery documentation for more info.

Numpy isnan() fails on an array of floats (from pandas dataframe apply)

np.isnan can be applied to NumPy arrays of native dtype (such as np.float64):

In [99]: np.isnan(np.array([np.nan, 0], dtype=np.float64))
Out[99]: array([ True, False], dtype=bool)

but raises TypeError when applied to object arrays:

In [96]: np.isnan(np.array([np.nan, 0], dtype=object))
TypeError: ufunc 'isnan' not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule ''safe''

Since you have Pandas, you could use pd.isnull instead -- it can accept NumPy arrays of object or native dtypes:

In [97]: pd.isnull(np.array([np.nan, 0], dtype=float))
Out[97]: array([ True, False], dtype=bool)

In [98]: pd.isnull(np.array([np.nan, 0], dtype=object))
Out[98]: array([ True, False], dtype=bool)

Note that None is also considered a null value in object arrays.

How to add Drop-Down list (<select>) programmatically?

I have quickly made a function that can achieve this, it may not be the best way to do this but it simply works and should be cross browser, please also know that i am NOT a expert in JavaScript so any tips are great :)

Pure Javascript Create Element Solution

function createElement(){
    var element  = document.createElement(arguments[0]),
        text     = arguments[1],
        attr     = arguments[2],
        append   = arguments[3],
        appendTo = arguments[4];

    for(var key = 0; key < Object.keys(attr).length ; key++){
        var name = Object.keys(attr)[key],
             value = attr[name],
             tempAttr = document.createAttribute(name);
             tempAttr.value = value;
        element.setAttributeNode(tempAttr)
    }
    
    if(append){
        for(var _key = 0; _key < append.length; _key++) {
            element.appendChild(append[_key]);
        }
    }

    if(text) element.appendChild(document.createTextNode(text));

    if(appendTo){
        var target = appendTo === 'body' ? document.body : document.getElementById(appendTo);
        target.appendChild(element)
    }       

    return element;
}

lets see how we make this

<select name="drop1" id="Select1">
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="mercedes">Mercedes</option>
  <option value="audi">Audi</option>
</select>

here's how it works

    var options = [
        createElement('option', 'Volvo', {value: 'volvo'}),
        createElement('option', 'Saab', {value: 'saab'}),
        createElement('option', 'Mercedes', {value: 'mercedes'}),
        createElement('option', 'Audi', {value: 'audi'})
    ];


    createElement('select', null, // 'select' = name of element to create, null = no text to insert
        {id: 'Select1', name: 'drop1'}, // Attributes to attach
        [options[0], options[1], options[2], options[3]], // append all 4 elements
        'body' // append final element to body - this also takes a element by id without the #
    );

this is the params

createElement('tagName', 'Text to Insert', {any: 'attribute', here: 'like', id: 'mainContainer'}, [elements, to, append, to, this, element], 'body || container = where to append this element');

This function would suit if you have to append many element, if there is any way to improve this answer please let me know.

edit:

Here is a working demo

JSFiddle Demo

This can be highly customized to suit your project!

Create an array of strings

Another solution to this old question is the new container string array, introduced in Matlab 2016b. From what I read in the official Matlab docs, this container resembles a cell-array and most of the array-related functions should work out of the box. For your case, new solution would be:

a=repmat('Some text', 10, 1);

This solution resembles a Rich C's solution applied to string array.

Delete data with foreign key in SQL Server table

here you are adding the foreign key for your "Child" table

ALTER TABLE child
ADD FOREIGN KEY (P_Id)
REFERENCES parent(P_Id) 
ON DELETE CASCADE
ON UPDATE CASCADE;

After that if you make a DELETE query on "Parent" table like this

DELETE FROM parent WHERE .....

since the child has a reference to parent with DELETE CASCADE, the "Child" rows also will be deleted! along with the "parent".

Updating records codeigniter

How to update in codeignitor?

whenever you want to update same status with multiple rows you use where_in insteam of where or if you want to change only single record can use where.

below is my code

$conditionArray = array(1, 3, 4, 6);
$this->db->where_in("ip_id", $conditionArray);
$this->db->update($this->table, array("status" => 'active'));

its working perfect.

Node.js https pem error: routines:PEM_read_bio:no start line

For me, the solution was to replace \\n (getting formatted into the key in a weird way) in place of \n

Replace your key: <private or public key> with key: (<private or public key>).replace(new RegExp("\\\\n", "\g"), "\n")

How to do perspective fixing?

The simple solution is to just remap coordinates from the original to the final image, copying pixels from one coordinate space to the other, rounding off as necessary -- which may result in some pixels being copied several times adjacent to each other, and other pixels being skipped, depending on whether you're stretching or shrinking (or both) in either dimension. Make sure your copying iterates through the destination space, so all pixels are covered there even if they're painted more than once, rather than thru the source which may skip pixels in the output.

The better solution involves calculating the corresponding source coordinate without rounding, and then using its fractional position between pixels to compute an appropriate average of the (typically) four pixels surrounding that location. This is essentially a filtering operation, so you lose some resolution -- but the result looks a LOT better to the human eye; it does a much better job of retaining small details and avoids creating straight-line artifacts which humans find objectionable.

Note that the same basic approach can be used to remap flat images onto any other shape, including 3D surface mapping.

Python name 'os' is not defined

Just add:

import os

in the beginning, before:

from settings import PROJECT_ROOT

This will import the python's module os, which apparently is used later in the code of your module without being imported.

Is it possible to set an object to null?

"an object" of what type?

You can certainly assign NULL (and nullptr) to objects of pointer types, and it is implementation defined if you can assign NULL to objects of arithmetic types.

If you mean objects of some class type, the answer is NO (excepting classes that have operator= accepting pointer or arithmetic types)

"empty" is more plausible, as many types have both copy assignment and default construction (often implicitly). To see if an existing object is like a default constructed one, you will also need an appropriate bool operator==

Use a cell value in VBA function with a variable

No need to activate or selection sheets or cells if you're using VBA. You can access it all directly. The code:

Dim rng As Range
For Each rng In Sheets("Feuil2").Range("A1:A333")
    Sheets("Classeur2.csv").Cells(rng.Value, rng.Offset(, 1).Value) = "1"
Next rng

is producing the same result as Joe's code.

If you need to switch sheets for some reasons, use Application.ScreenUpdating = False at the beginning of your macro (and Application.ScreenUpdating=True at the end). This will remove the screenflickering - and speed up the execution.

Async await in linq select

Existing code is working, but is blocking the thread.

.Select(async ev => await ProcessEventAsync(ev))

creates a new Task for every event, but

.Select(t => t.Result)

blocks the thread waiting for each new task to end.

In the other hand your code produce the same result but keeps asynchronous.

Just one comment on your first code. This line

var tasks = await Task.WhenAll(events...

will produce a single Task<TResult[]> so the variable should be named in singular.

Finally your last code make the same but is more succinct.

For reference: Task.Wait / Task.WhenAll

Getting only Month and Year from SQL DATE

select month(dateField), year(dateField)

Get UTC time and local time from NSDate object

The documentation says that the date method returns a new date set to the current date and time regardless of the language used.

The issue probably sits somewhere where you present the date using NSDateFormatter. NSDate is just a point on a time line. There is no time zones when talking about NSDate. I made a test.

Swift

print(NSDate())

Output: 2014-07-23 17:56:45 +0000

Objective-C

NSLog(@"%@", [NSDate date]);

Output: 2014-07-23 17:58:15 +0000

Result - No difference.

Why is my toFixed() function not working?

Example simple (worked):

var a=Number.parseFloat($("#budget_project").val()); // from input field
var b=Number.parseFloat(html); // from ajax
var c=a-b;
$("#result").html(c.toFixed(2)); // put to id='result' (div or others)

Visual Studio keyboard shortcut to automatically add the needed 'using' statement

  • Context Menu key (one one with the menu on it, next to the right Windows key)
  • Then choose "Resolve" from the menu. That can be done by pressing "s".

Linking static libraries to other static libraries

On Linux or MingW, with GNU toolchain:

ar -M <<EOM
    CREATE libab.a
    ADDLIB liba.a
    ADDLIB libb.a
    SAVE
    END
EOM
ranlib libab.a

Of if you do not delete liba.a and libb.a, you can make a "thin archive":

ar crsT libab.a liba.a libb.a

On Windows, with MSVC toolchain:

lib.exe /OUT:libab.lib liba.lib libb.lib

how to check if item is selected from a comboBox in C#

Here is the perfect coding which checks whether the Combo Box Item is Selected or not

if (string.IsNullOrEmpty(comboBox1.Text))
{
    MessageBox.Show("No Item is Selected"); 
}
else
{
    MessageBox.Show("Item Selected is:" + comboBox1.Text);
}

Overlay a background-image with an rgba background-color

The solution by PeterVR has the disadvantage that the additional color displays on top of the entire HTML block - meaning that it also shows up on top of div content, not just on top of the background image. This is fine if your div is empty, but if it is not using a linear gradient might be a better solution:

<div class="the-div">Red text</div>

<style type="text/css">
  .the-div
  {
    background-image: url("the-image.png");
    color: #f00;
    margin: 10px;
    width: 200px;
    height: 80px;
  }
  .the-div:hover
  {
    background-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
    background-image: -moz-linear-gradient(top, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
    background-image: -o-linear-gradient(top, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
    background-image: -ms-linear-gradient(top, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
    background-image: -webkit-gradient(linear, left top, left bottom, from(rgba(0, 0, 0, 0.1)), to(rgba(0, 0, 0, 0.1))), url("the-image.png");
    background-image: -webkit-linear-gradient(top, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
  }
</style>

See fiddle. Too bad that gradient specifications are currently a mess. See compatibility table, the code above should work in any browser with a noteworthy market share - with the exception of MSIE 9.0 and older.

Edit (March 2017): The state of the web got far less messy by now. So the linear-gradient (supported by Firefox and Internet Explorer) and -webkit-linear-gradient (supported by Chrome, Opera and Safari) lines are sufficient, additional prefixed versions are no longer necessary.

How do I retrieve query parameters in Spring Boot?

Use @RequestParam

@RequestMapping(value="user", method = RequestMethod.GET)
public @ResponseBody Item getItem(@RequestParam("data") String itemid){

    Item i = itemDao.findOne(itemid);              
    String itemName = i.getItemName();
    String price = i.getPrice();
    return i;
}

How can I resolve the error: "The command [...] exited with code 1"?

I had the same issue. Tried all the above answers. It was actually complained about a .dll file. I clean the project in Visual Studio but the .dll file still remains, so I deleted in manually from the bin folder and it worked.

How to get the Android device's primary e-mail address

Android locked down GET_ACCOUNTS recently so some of the answers did not work for me. I got this working on Android 7.0 with the caveat that your users have to endure a permission dialog.

AndroidManifest.xml

<uses-permission android:name="android.permission.GET_ACCOUNTS"/>

MainActivity.java

package com.example.patrick.app2;
import android.content.pm.PackageManager;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.accounts.AccountManager;
import android.accounts.Account;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.*;

public class MainActivity extends AppCompatActivity {

    final static int requestcode = 4; //arbitrary constant less than 2^16

    private static String getEmailId(Context context) {
        AccountManager accountManager = AccountManager.get(context);
        Account[] accounts = accountManager.getAccountsByType("com.google");
        Account account;
        if (accounts.length > 0) {
            account = accounts[0];
        } else {
            return "length is zero";
        }
        return account.name;
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        switch (requestCode) {
            case requestcode:
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                    String emailAddr = getEmailId(getApplicationContext());
                    ShowMessage(emailAddr);

                } else {
                    ShowMessage("Permission Denied");
                }
        }
    }

    public void ShowMessage(String email)
    {
        AlertDialog alertDialog = new AlertDialog.Builder(MainActivity.this).create();
        alertDialog.setTitle("Alert");
        alertDialog.setMessage(email);
        alertDialog.setButton(AlertDialog.BUTTON_NEUTRAL, "OK",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
                    }
                });
        alertDialog.show();
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Context context = getApplicationContext();

        if ( ContextCompat.checkSelfPermission( context, android.Manifest.permission.GET_ACCOUNTS )
                != PackageManager.PERMISSION_GRANTED )
        {
            ActivityCompat.requestPermissions( this, new String[]
                            {  android.Manifest.permission.GET_ACCOUNTS  },requestcode );
        }
        else
        {
            String possibleEmail = getEmailId(getApplicationContext());
            ShowMessage(possibleEmail);
        }
    }
}

Cannot implicitly convert type from Task<>

You need to make TestGetMethod async too and attach await in front of GetIdList(); will unwrap the task to List<int>, So if your helper function is returning Task make sure you have await as you are calling the function async too.

public Task<List<int>> TestGetMethod()
{
    return GetIdList();
}    

async Task<List<int>> GetIdList()
{
    using (HttpClient proxy = new HttpClient())
    {
        string response = await proxy.GetStringAsync("www.test.com");
        List<int> idList = JsonConvert.DeserializeObject<List<int>>();
        return idList;
    }
}

Another option

public async void TestGetMethod(List<int> results)
{
    results = await GetIdList(); // await will unwrap the List<int>
}

Function to get yesterday's date in Javascript in format DD/MM/YYYY

The problem here seems to be that you're reassigning $today by assigning a string to it:

$today = $dd+'/'+$mm+'/'+$yyyy;

Strings don't have getDate.

Also, $today.getDate()-1 just gives you the day of the month minus one; it doesn't give you the full date of 'yesterday'. Try this:

$today = new Date();
$yesterday = new Date($today);
$yesterday.setDate($today.getDate() - 1); //setDate also supports negative values, which cause the month to rollover.

Then just apply the formatting code you wrote:

var $dd = $yesterday.getDate();
var $mm = $yesterday.getMonth()+1; //January is 0!

var $yyyy = $yesterday.getFullYear();
if($dd<10){$dd='0'+$dd} if($mm<10){$mm='0'+$mm} $yesterday = $dd+'/'+$mm+'/'+$yyyy;

Because of the last statement, $yesterday is now a String (not a Date) containing the formatted date.

How to resolve Unable to load authentication plugin 'caching_sha2_password' issue

As Mentioned in above repilies:

Starting with MySQL 8.0.4, the MySQL team changed the default authentication plugin for MySQL server from mysql_native_password to caching_sha2_password.

So there are three ways to resolve this issue:

 1. drop USER 'user_name'@'localhost';
    flush privileges;
    CREATE USER 'user_name'@'localhost' IDENTIFIED BY 'user_name';
    GRANT ALL PRIVILEGES ON * . * TO 'user_name'@'localhost';
    ALTER USER 'user_name'@'localhost' IDENTIFIED WITH mysql_native_password BY 
    'user_name';

 2. drop USER 'user_name'@'localhost';
    flush privileges;
    CREATE USER 'user_name'@'localhost' IDENTIFIED WITH mysql_native_password BY 'user_name';
GRANT ALL PRIVILEGES ON * . * TO 'user_name'@'localhost'

 3. If the user is already created, the use the following command:

    ALTER USER 'user_name'@'localhost' IDENTIFIED WITH mysql_native_password BY 
        'user_name';

Resize image in PHP

Simple Use PHP function (imagescale):

Syntax:

imagescale ( $image , $new_width , $new_height )

Example:

Step: 1 Read the file

$image_name =  'path_of_Image/Name_of_Image.jpg|png';      

Step: 2: Load the Image File

 $image = imagecreatefromjpeg($image_name); // For JPEG
//or
 $image = imagecreatefrompng($image_name);   // For PNG

Step: 3: Our Life-saver comes in '_' | Scale the image

   $imgResized = imagescale($image , 500, 400); // width=500 and height = 400
//  $imgResized is our final product

Note: imagescale will work for (PHP 5 >= 5.5.0, PHP 7)

Source : Click to Read more

Xcode 7.2 no matching provisioning profiles found

Try restarting XCode first, before trying these other answers. I was about to follow the advice given in other answers, then noticed multiple people saying that restarting XCode was necessary after all the steps. All I did was restart XCode and it fixed the problem. Who knows if it'll fix the problem for you, but it's worth a shot before trying the other solutions. I'm on XCode 7.2.1.

How to remove a key from HashMap while iterating over it?

Try:

Iterator<Map.Entry<String,String>> iter = testMap.entrySet().iterator();
while (iter.hasNext()) {
    Map.Entry<String,String> entry = iter.next();
    if("Sample".equalsIgnoreCase(entry.getValue())){
        iter.remove();
    }
}

With Java 1.8 and onwards you can do the above in just one line:

testMap.entrySet().removeIf(entry -> "Sample".equalsIgnoreCase(entry.getValue()));

How to include a font .ttf using CSS?

Did you try format?

@font-face {
  font-family: 'The name of the Font Family Here';
  src: URL('font.ttf') format('truetype');
}

Read this article: http://css-tricks.com/snippets/css/using-font-face/

Also, might depend on browser as well.

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

Using %.2f in printf. It only print 2 decimal points.

Example:

printf("%.2f", 37.777779);

Output:

37.77

Limit results in jQuery UI Autocomplete

In my case this works fine:

source:function(request, response){
    var numSumResult = 0;
    response(
        $.map(tblData, function(rowData) {
            if (numSumResult < 10) {
                numSumResult ++;
                return {
                    label:          rowData.label,
                    value:          rowData.value,
                }
            }
        })
    );
},

Where to place $PATH variable assertions in zsh?

I had similar problem (in bash terminal command was working correctly but zsh showed command not found error)

Solution:


just paste whatever you were earlier pasting in ~/.bashrc to:

~/.zshrc

Should I use != or <> for not equal in T-SQL?

'<>' is from the SQL-92 standard and '!=' is a proprietary T-SQL operator. It's available in other databases as well, but since it isn't standard you have to take it on a case-by-case basis.

In most cases, you'll know what database you're connecting to so this isn't really an issue. At worst you might have to do a search and replace in your SQL.

Classpath including JAR within a JAR

Not without writing your own class loader. You can add jars to the jar's classpath, but they must be co-located, not contained in the main jar.

How to parse month full form string using DateFormat in Java?

val currentTime = Calendar.getInstance().time
SimpleDateFormat("MMMM", Locale.getDefault()).format(date.time)

How to include libraries in Visual Studio 2012?

In code level also, you could add your lib to the project using the compiler directives #pragma.

example:

#pragma comment( lib, "yourLibrary.lib" )

Referencing Row Number in R

Perhaps with dataframes one of the most easy and practical solution is:

data = dplyr::mutate(data, rownum=row_number())

Function names in C++: Capitalize or not?

The most common ones I see in production code are (in this order):

myFunctionName     // lower camel case

MyFunctionName     // upper camel case

my_function_name   // K & R ?

I find the naming convention a programmer uses in C++ code usually has something to do with their programming background.

E.g. ex-java programmers tend to use lower camel case for functions

YouTube: How to present embed video with sound muted

Try this

<iframe width="420" height="315" src="http://www.youtube.com/embed/
HeQ39bLsoTI?autoplay=1&cc_load_policy=1" volume="0" frameborder="0"
allowfullscreen></iframe>

don't forget to write volume="0"

How do I run a single test using Jest?

From the command line, use the --testNamePattern or -t flag:

jest -t 'fix-order-test'

This will only run tests that match the test name pattern you provide. It's in the Jest documentation.

Another way is to run tests in watch mode, jest --watch, and then press P to filter the tests by typing the test file name or T to run a single test name.


If you have an it inside of a describe block, you have to run

jest -t '<describeString> <itString>'

Is it valid to have a html form inside another html form?

As workaround you could use formaction attribute on submit button. And just use different names on your inputs.

<form action="a">
<input.../>
    <!-- Form 2 inputs -->
    <input.../>
    <input.../>
    <input.../>
    <input type="submit" formaction="b">

</form>
<input.../>

How to kill/stop a long SQL query immediately?

  1. First, you need to display/check all running queries using below query-

    SELECT text, GETDATE(), *
    FROM sys.dm_exec_requests
    CROSS APPLY sys.dm_exec_sql_text(sql_handle)
    
  2. Find Session-Id and Description for respective all running queries and then copy specific query's Session-Id which you want to kill/stop immediately.

  3. Kill/stop specific query using Session-Id using this query:

    Kill Session-id
    

    Example:

    kill 125 --125 is my Session-Id
    

matplotlib set yaxis label size

If you are using the 'pylab' for interactive plotting you can set the labelsize at creation time with pylab.ylabel('Example', fontsize=40).

If you use pyplot programmatically you can either set the fontsize on creation with ax.set_ylabel('Example', fontsize=40) or afterwards with ax.yaxis.label.set_size(40).

Git submodule head 'reference is not a tree' error

This error can mean that a commit is missing in the submodule. That is, the repository (A) has a submodule (B). A wants to load B so that it is pointing to a certain commit (in B). If that commit is somehow missing, you'll get that error. Once possible cause: the reference to the commit was pushed in A, but the actual commit was not pushed from B. So I'd start there.

Less likely, there's a permissions problem, and the commit cannot be pulled (possible if you're using git+ssh).

Make sure the submodule paths look ok in .git/config and .gitmodules.

One last thing to try - inside the submodule directory: git reset HEAD --hard

How to resolve compiler warning 'implicit declaration of function memset'

A good way to findout what header file you are missing:

 man <section> <function call>

To find out the section use:

apropos <function call>

Example:

 man 3 memset
 man 2 send

Edit in response to James Morris:

  • Section | Description
  • 1 General commands
  • 2 System calls
  • 3 C library functions
  • 4 Special files (usually devices, those found in /dev) and drivers
  • 5 File formats and conventions
  • 6 Games and screensavers
  • 7 Miscellanea
  • 8 System administration commands and daemons

Source: Wikipedia Man Page

Spring-Security-Oauth2: Full authentication is required to access this resource

I had the same problem, but I solve this with the following class:

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.crypto.password.NoOpPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;

@Configuration
@EnableWebSecurity
public class OAuthSecurityConfiguration extends WebSecurityConfigurerAdapter {

    @Bean
    @Override
    public AuthenticationManager authenticationManager() throws Exception {
        return super.authenticationManager();
    }

    @Bean
    public PasswordEncoder passwordEncoder() {
        return NoOpPasswordEncoder.getInstance();
    }
}

How to assign bean's property an Enum value in Spring config file?

Using SPEL and P-NAMESPACE:

<beans...
xmlns:p="http://www.springframework.org/schema/p" ...>
..
<bean name="someName" class="my.pkg.classes"
    p:type="#{T(my.pkg.types.MyEnumType).TYPE1}"/>

parsing a tab-separated file in Python

Like this:

>>> s='1\t2\t3\t4\t5'
>>> [x for x in s.split('\t')]
['1', '2', '3', '4', '5']

For a file:

# create test file:
>>> with open('tabs.txt','w') as o:
...    s='\n'.join(['\t'.join(map(str,range(i,i+10))) for i in [0,10,20,30]])
...    print >>o, s

#read that file:
>>> with open('tabs.txt','r') as f:
...    LoL=[x.strip().split('\t') for x in f]
... 
>>> LoL
[['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'], 
 ['10', '11', '12', '13', '14', '15', '16', '17', '18', '19'], 
 ['20', '21', '22', '23', '24', '25', '26', '27', '28', '29'], 
 ['30', '31', '32', '33', '34', '35', '36', '37', '38', '39']]
>>> LoL[2][3]
23

If you want the input transposed:

>>> with open('tabs.txt','r') as f:
...    LoT=zip(*(line.strip().split('\t') for line in f))
... 
>>> LoT[2][3]
'32'

Or (better still) use the csv module in the default distribution...

How to hide image broken Icon using only CSS/HTML?

I liked the answer by Nick and was playing around with this solution. Found a cleaner method. Since ::before/::after pseudos don't work on replaced elements like img and object they will only work if the object data (src) is not loaded. It keeps the HTML more clean and will only add the pseudo if the object fails to load.

_x000D_
_x000D_
object {_x000D_
  position: relative;_x000D_
  float: left;_x000D_
  display: block;_x000D_
  width: 200px;_x000D_
  height: 200px;_x000D_
  margin-right: 20px;_x000D_
  border: 1px solid black;_x000D_
}_x000D_
object::after {_x000D_
  position: absolute;_x000D_
  top: 0;_x000D_
  left: 0;_x000D_
  display: block;_x000D_
  width: 100%;_x000D_
  height: 100%;_x000D_
  content: '';_x000D_
  background: red url("http://placehold.it/200x200");_x000D_
}
_x000D_
<object data="http://lorempixel.com/200/200/people/1" type="image/png"></object>_x000D_
_x000D_
<object data="http://broken.img/url" type="image/png"></object>
_x000D_
_x000D_
_x000D_

How do I get a list of files in a directory in C++?

If you're in Windows & using MSVC, the MSDN library has sample code that does this.

And here's the code from that link:

#include <windows.h>
#include <tchar.h> 
#include <stdio.h>
#include <strsafe.h>

void ErrorHandler(LPTSTR lpszFunction);

int _tmain(int argc, TCHAR *argv[])
{
   WIN32_FIND_DATA ffd;
   LARGE_INTEGER filesize;
   TCHAR szDir[MAX_PATH];
   size_t length_of_arg;
   HANDLE hFind = INVALID_HANDLE_VALUE;
   DWORD dwError=0;

   // If the directory is not specified as a command-line argument,
   // print usage.

   if(argc != 2)
   {
      _tprintf(TEXT("\nUsage: %s <directory name>\n"), argv[0]);
      return (-1);
   }

   // Check that the input path plus 2 is not longer than MAX_PATH.

   StringCchLength(argv[1], MAX_PATH, &length_of_arg);

   if (length_of_arg > (MAX_PATH - 2))
   {
      _tprintf(TEXT("\nDirectory path is too long.\n"));
      return (-1);
   }

   _tprintf(TEXT("\nTarget directory is %s\n\n"), argv[1]);

   // Prepare string for use with FindFile functions.  First, copy the
   // string to a buffer, then append '\*' to the directory name.

   StringCchCopy(szDir, MAX_PATH, argv[1]);
   StringCchCat(szDir, MAX_PATH, TEXT("\\*"));

   // Find the first file in the directory.

   hFind = FindFirstFile(szDir, &ffd);

   if (INVALID_HANDLE_VALUE == hFind) 
   {
      ErrorHandler(TEXT("FindFirstFile"));
      return dwError;
   } 

   // List all the files in the directory with some info about them.

   do
   {
      if (ffd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
      {
         _tprintf(TEXT("  %s   <DIR>\n"), ffd.cFileName);
      }
      else
      {
         filesize.LowPart = ffd.nFileSizeLow;
         filesize.HighPart = ffd.nFileSizeHigh;
         _tprintf(TEXT("  %s   %ld bytes\n"), ffd.cFileName, filesize.QuadPart);
      }
   }
   while (FindNextFile(hFind, &ffd) != 0);

   dwError = GetLastError();
   if (dwError != ERROR_NO_MORE_FILES) 
   {
      ErrorHandler(TEXT("FindFirstFile"));
   }

   FindClose(hFind);
   return dwError;
}


void ErrorHandler(LPTSTR lpszFunction) 
{ 
    // Retrieve the system error message for the last-error code

    LPVOID lpMsgBuf;
    LPVOID lpDisplayBuf;
    DWORD dw = GetLastError(); 

    FormatMessage(
        FORMAT_MESSAGE_ALLOCATE_BUFFER | 
        FORMAT_MESSAGE_FROM_SYSTEM |
        FORMAT_MESSAGE_IGNORE_INSERTS,
        NULL,
        dw,
        MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
        (LPTSTR) &lpMsgBuf,
        0, NULL );

    // Display the error message and exit the process

    lpDisplayBuf = (LPVOID)LocalAlloc(LMEM_ZEROINIT, 
        (lstrlen((LPCTSTR)lpMsgBuf)+lstrlen((LPCTSTR)lpszFunction)+40)*sizeof(TCHAR)); 
    StringCchPrintf((LPTSTR)lpDisplayBuf, 
        LocalSize(lpDisplayBuf) / sizeof(TCHAR),
        TEXT("%s failed with error %d: %s"), 
        lpszFunction, dw, lpMsgBuf); 
    MessageBox(NULL, (LPCTSTR)lpDisplayBuf, TEXT("Error"), MB_OK); 

    LocalFree(lpMsgBuf);
    LocalFree(lpDisplayBuf);
}

int to hex string

Use ToString("X4").

The 4 means that the string will be 4 digits long.

Reference: The Hexadecimal ("X") Format Specifier on MSDN.

Disable clipboard prompt in Excel VBA on workbook close

There is a simple work around. The alert only comes up when you have a large amount of data in your clipboard. Just copy a random cell before you close the workbook and it won't show up anymore!

How to use SVN, Branch? Tag? Trunk?

A lot of good comments here, but something that hasn't been mentioned is commit messages. These should be mandatory and meaningful. Especially with branching/merging. This will allow you to keep track of what changes are relevant to which bugs features.

for example svn commit . -m 'bug #201 fixed y2k bug in code' will tell anyone who looks at the history what that revision was for.

Some bug tracking systems (eg trac) can look in the repository for these messages and associate them with the tickets. Which makes working out what changes are associated with each ticket very easy.

Simple JavaScript Checkbox Validation

var confirm=document.getElementById("confirm").value;
         if((confirm.checked==false)
         {
         alert("plz check the checkbox field");
         document.getElementbyId("confirm").focus();
         return false;
         }

How to delete a folder and all contents using a bat file in windows?

  1. del /s /q c:\where ever the file is\*
  2. rmdir /s /q c:\where ever the file is\
  3. mkdir c:\where ever the file is\

ansible: lineinfile for several lines?

You can use a loop to do it. Here's an example using a with_items loop:

- name: Set some kernel parameters
  lineinfile:
    dest: /etc/sysctl.conf
    regexp: "{{ item.regexp }}"
    line: "{{ item.line }}"
  with_items:
    - { regexp: '^kernel.shmall', line: 'kernel.shmall = 2097152' }
    - { regexp: '^kernel.shmmax', line: 'kernel.shmmax = 134217728' }
    - { regexp: '^fs.file-max', line: 'fs.file-max = 65536' }

Use jQuery to change an HTML tag?

Once a dom element is created, the tag is immutable, I believe. You'd have to do something like this:

$(this).replaceWith($('<h5>' + this.innerHTML + '</h5>'));

How to send a header using a HTTP request through a curl call?

I use Postman.

Execute whatever call you want to do. Then, postman provides a handy tool to show the curl code .

Run it in the terminal. enter image description here

enter image description here

Email address validation using ASP.NET MVC data type attributes

You need to use RegularExpression Attribute, something like this:

[RegularExpression("^[a-zA-Z0-9_\\.-]+@([a-zA-Z0-9-]+\\.)+[a-zA-Z]{2,6}$", ErrorMessage = "E-mail is not valid")]

And don't delete [Required] because [RegularExpression] doesn't affect empty fields.

how to log in to mysql and query the database from linux terminal

if u got still no access to db, 1. in ur error message is set no password right? then first do mysqlpasswd 'username' after that enter and then give it a password type again as requested and then try to access again with mysql -p if you are root

List of zeros in python

zlists = [[0] * i for i in range(10)]

zlists[0] is a list of 0 zeroes, zlists[1] is a list of 1 zero, zlists[2] is a list of 2 zeroes, etc.

Is it possible to set ENV variables for rails development environment in my code?

The way I am trying to do this in my question actually works!

# environment/development.rb

ENV['admin_password'] = "secret" 

I just had to restart the server. I thought running reload! in rails console would be enough but I also had to restart the web server.

I am picking my own answer because I feel this is a better place to put and set the ENV variables

What does the Ellipsis object do?

Summing up what others have said, as of Python 3, Ellipsis is essentially another singleton constant similar to None, but without a particular intended use. Existing uses include:

  • In slice syntax to represent the full slice in remaining dimensions
  • In type hinting to indicate only part of a type(Callable[..., int] or Tuple[str, ...])
  • In type stub files to indicate there is a default value without specifying it

Possible uses could include:

  • As a default value for places where None is a valid option
  • As the content for a function you haven't implemented yet

nodejs send html file to client

Try your code like this:

var app = express();
app.get('/test', function(req, res) {
    res.sendFile('views/test.html', {root: __dirname })
});
  1. Use res.sendFile instead of reading the file manually so express can handle setting the content-type properly for you.

  2. You don't need the app.engine line, as that is handled internally by express.

How do you compare two version Strings in Java?

I created simple utility for comparing versions on Android platform using Semantic Versioning convention. So it works only for strings in format X.Y.Z (Major.Minor.Patch) where X, Y, and Z are non-negative integers. You can find it on my GitHub.

Method Version.compareVersions(String v1, String v2) compares two version strings. It returns 0 if the versions are equal, 1 if version v1 is before version v2, -1 if version v1 is after version v2, -2 if version format is invalid.

Why, Fatal error: Class 'PHPUnit_Framework_TestCase' not found in ...?

For those arriving here after updating phpunit to version 6 or greater released on 2017-02-03 (e.g. with composer), you may be getting this error because phpunit code is now namespaced (check changelog).

You will need to refactor things like \PHPUnit_Framework_TestCase to \PHPUnit\Framework\TestCase

How to pass a value from one jsp to another jsp page?

Use sessions

On your search.jsp

Put your scard in sessions using session.setAttribute("scard","scard")

//the 1st variable is the string name that you will retrieve in ur next page,and the 2nd variable is the its value,i.e the scard value.

And in your next page you retrieve it using session.getAttribute("scard")

UPDATE

<input type="text" value="<%=session.getAttribute("scard")%>"/>

IPython/Jupyter Problems saving notebook as PDF

I am using Anaconda-Jupyter Notebook on OS: Ubuntu 16.0 for Python programming.

Install Nbconvert, Pandoc, and Tex:

Open a terminal and implement the following commands in it.

Install Nbconvert: though it's part of the Jupyter ecosystem still install it once again

$conda install nbconvert

Or

$pip install nbconvert

But I will recommend using conda instead pip if you are using anaconda

Install Pandoc: since Nbconvert uses Pandoc for converting markdown to formats other than HTML. Type following command

$sudo apt-get install pandoc

Install TeX: For converting to PDF, nbconvert uses the TeX. Type following command

$sudo apt-get install texlive-xetex

After execution of these commands, close the opened notebooks refresh the home page Or restart the kernel of the opened notebook. Now try to download notebook as a pdf :)

Note: For more details, please refer the official documentation:
https://nbconvert.readthedocs.io/en/latest/install.html

How do I combine two data-frames based on two columns?

You can also use the join command (dplyr).

For example:

new_dataset <- dataset1 %>% right_join(dataset2, by=c("column1","column2"))

How to show and update echo on same line

The rest of answers are pretty good, but just wanted to add some extra information in case someone comes here looking for a solution to replace/update a multiline echo.

So I would like to share an example with you all. The following script was tried on a CentOS system and uses "timedatectl" command which basically prints some detailed time information of your system.

I decided to use that command as its output contains multiple lines and works perfectly for the example below:

#!/bin/bash
while true; do
  COMMAND=$(timedatectl) #Save command result in a var.
  echo "$COMMAND" #Print command result, including new lines.

  sleep 3 #Keep above's output on screen during 3 seconds before clearing it

  #Following code clears previously printed lines
  LINES=$(echo "$COMMAND" | wc -l) #Calculate number of lines for the output previously printed
  for (( i=1; i <= $(($LINES)); i++ ));do #For each line printed as a result of "timedatectl"
    tput cuu1 #Move cursor up by one line
    tput el #Clear the line
  done

done

The above will print the result of "timedatectl" forever and will replace the previous echo with updated results.

I have to mention that this code is only an example, but maybe not the best solution for you depending on your needs. A similar command that would do almost the same (at least visually) is "watch -n 3 timedatectl".

But that's a different story. :)

Hope that helps!

TypeError: 'undefined' is not an object

I'm not sure how you could just check if something isn't undefined and at the same time get an error that it is undefined. What browser are you using?

You could check in the following way (extra = and making length a truthy evaluation)

if (typeof(sub.from) !== 'undefined' && sub.from.length) {

[update]

I see that you reset sub and thereby reset sub.from but fail to re check if sub.from exist:

for (var i = 0; i < sub.from.length; i++) {//<== assuming sub.from.exist
            mainid = sub.from[i]['id'];
            var sub = afcHelper_Submissions[mainid]; // <== re setting sub

My guess is that the error is not on the if statement but on the for(i... statement. In Firebug you can break automatically on an error and I guess it'll break on that line (not on the if statement).

How to split a dataframe string column into two columns?

There might be a better way, but this here's one approach:

                            row
    0       00000 UNITED STATES
    1             01000 ALABAMA
    2  01001 Autauga County, AL
    3  01003 Baldwin County, AL
    4  01005 Barbour County, AL
df = pd.DataFrame(df.row.str.split(' ',1).tolist(),
                                 columns = ['flips','row'])
   flips                 row
0  00000       UNITED STATES
1  01000             ALABAMA
2  01001  Autauga County, AL
3  01003  Baldwin County, AL
4  01005  Barbour County, AL