Programs & Examples On #Gps

Abbreviation for Global Positioning System; a navigational system using satellite signals to fix the location of a radio receiver on or above the earth's surface. Also "GPS" refers to the radio receiver so used.

How to get current location in Android

I'm using this tutorial and it works nicely for my application.

In my activity I put this code:

GPSTracker tracker = new GPSTracker(this);
    if (!tracker.canGetLocation()) {
        tracker.showSettingsAlert();
    } else {
        latitude = tracker.getLatitude();
        longitude = tracker.getLongitude();
    }

also check if your emulator runs with Google API

Android "gps requires ACCESS_FINE_LOCATION" error, even though my manifest file contains this

CAUSE: "Beginning in Android 6.0 (API level 23), users grant permissions to apps while the app is running, not when they install the app." In this case, "ACCESS_FINE_LOCATION" is a "dangerous permission and for that reason, you get this 'java.lang.SecurityException: "gps" location provider requires ACCESS_FINE_LOCATION permission.' error (https://developer.android.com/training/permissions/requesting.html).

SOLUTION: Implementing the code provided at https://developer.android.com/training/permissions/requesting.html under the "Request the permissions you need" and "Handle the permissions request response" headings.

How to set fake GPS location on IOS real device

you can do it on real device by run device in Debug mode

Click Debug->Simulate Location -> add .gpx file for your location during run time

How does GPS in a mobile phone work exactly?

There's 3 satellites at least that you must be able to receive from of the 24-32 out there, and they each broadcast a time from a synchronized atomic clock. The differences in those times that you receive at any one time tell you how long the broadcast took to reach you, and thus where you are in relation to the satellites. So, it sort of reads from something, but it doesn't connect to that thing. Note that this doesn't tell you your orientation, many GPSes fake that (and speed) by interpolating data points.

If you don't count the cost of the receiver, it's a free service. Apparently there's higher resolution services out there that are restricted to military use. Those are likely a fixed cost for a license to decrypt the signals along with a confidentiality agreement.

Now your device may support GPS tracking, in which case it might communicate, say via GPRS, to a database which will store the location the device has found itself to be at, so that multiple devices may be tracked. That would require some kind of connection.

Maps are either stored on the device or received over a connection. Navigation is computed based on those maps' databases. These likely are a licensed item with a cost associated, though if you use a service like Google Maps they have the license with NAVTEQ and others.

Does GPS require Internet?

I've found out that GPS does not need Internet, BUT of course if you need to download maps, you will need a data connection or wifi.

http://androidforums.com/samsung-fascinate/288871-gps-independent-3g-wi-fi.html http://www.droidforums.net/forum/droid-applications/63145-does-google-navigation-gps-requires-3g-work.html

Get current location of user in Android without using GPS or internet

It appears that it is possible to track a smart phone without using GPS.

Sources:

Primary: "PinMe: Tracking a Smartphone User around the World"

Secondary: "How to Track a Cellphone Without GPS—or Consent"

I have not yet found a link to the team's final code. When I do I will post, if another has not done so.

Android Location Manager, Get GPS location ,if no GPS then get to Network Provider location

The recommended way to do this is to use LocationClient:

First, define location update interval values. Adjust this to your needs.

private static final int MILLISECONDS_PER_SECOND = 1000;
private static final long UPDATE_INTERVAL = MILLISECONDS_PER_SECOND * UPDATE_INTERVAL_IN_SECONDS;
private static final int FASTEST_INTERVAL_IN_SECONDS = 1;
private static final long FASTEST_INTERVAL = MILLISECONDS_PER_SECOND * FASTEST_INTERVAL_IN_SECONDS;

Have your Activity implement GooglePlayServicesClient.ConnectionCallbacks, GooglePlayServicesClient.OnConnectionFailedListener, and LocationListener.

public class LocationActivity extends Activity implements 
GooglePlayServicesClient.ConnectionCallbacks, GooglePlayServicesClient.OnConnectionFailedListener, LocationListener {}

Then, set up a LocationClientin the onCreate() method of your Activity:

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    mLocationClient = new LocationClient(this, this, this);

    mLocationRequest = LocationRequest.create();
    mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
    mLocationRequest.setInterval(UPDATE_INTERVAL);
    mLocationRequest.setFastestInterval(FASTEST_INTERVAL);
}

Add the required methods to your Activity; onConnected() is the method that is called when the LocationClientconnects. onLocationChanged() is where you'll retrieve the most up-to-date location.

@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
    Log.w(TAG, "Location client connection failed");
}

@Override
public void onConnected(Bundle dataBundle) {
    Log.d(TAG, "Location client connected");
    mLocationClient.requestLocationUpdates(mLocationRequest, this); 
}

@Override
public void onDisconnected() {
    Log.d(TAG, "Location client disconnected");
}

@Override
public void onLocationChanged(Location location) {
    if (location != null) {
        Log.d(TAG, "Updated Location: " + Double.toString(location.getLatitude()) + "," + Double.toString(location.getLongitude()));
    } else {
        Log.d(TAG, "Updated location NULL");
    } 
}     

Be sure to connect/disconnect the LocationClient so it's only using extra battery when absolutely necessary and so the GPS doesn't run indefinitely. The LocationClient must be connected in order to get data from it.

public void onResume() {
    super.onResume();
    mLocationClient.connect();
}

public void onStop() {
    if (mLocationClient.isConnected()) {
        mLocationClient.removeLocationUpdates(this);
    }
    mLocationClient.disconnect();
    super.onStop();
}

Get the user's location. First try using the LocationClient; if that fails, fall back to the LocationManager.

public Location getLocation() {
    if (mLocationClient != null && mLocationClient.isConnected()) {
        return mLocationClient.getLastLocation();
    } else {
        LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
        if (locationManager != null) {
            Location lastKnownLocationGPS = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
            if (lastKnownLocationGPS != null) {
                return lastKnownLocationGPS;
            } else {
                return locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
            }
        } else {
            return null;
        }
    }
}

Algorithm to find all Latitude Longitude locations within a certain distance from a given Lat Lng location

You may convert latitude-longitude to UTM format which is metric format that may help you to calculate distances. Then you can easily decide if point falls into specific location.

How to get Android GPS location

The initial issue is solved by changing lat and lon to double.

I want to add comment to solution with Location location = locationManager.getLastKnownLocation(bestProvider); It works to find out last known location when other app was lisnerning for that. If, for example, no app did that since device start, the code will return zeros (spent some time myself recently to figure that out).

Also, it's a good practice to stop listening when there is no need for that by locationManager.removeUpdates(this);

Also, even with permissions in manifest, the code works when location service is enabled in Android settings on a device.

How do I find out if the GPS of an Android device is enabled

In your LocationListener, implement onProviderEnabled and onProviderDisabled event handlers. When you call requestLocationUpdates(...), if GPS is disabled on the phone, onProviderDisabled will be called; if user enables GPS, onProviderEnabled will be called.

How do I get the current GPS location programmatically in Android?

You can find the location either by GPS_PROVIDER or NETWORK_PROVIDER.

Overview of location services in Android.

Here is one example which try to find the location using GPS. If your GPS is not available then try to use network for find the location.

GPSTracker.java

 public class GPSTracker extends Service implements LocationListener {

    private final Context mContext;

    // Flag for GPS status
    boolean isGPSEnabled = false;

    // Flag for network status
    boolean isNetworkEnabled = false;

    // Flag for GPS status
    boolean canGetLocation = false;

    Location location; // Location
    double latitude; // Latitude
    double longitude; // Longitude

    // The minimum distance to change Updates in meters
    private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters

    // The minimum time between updates in milliseconds
    private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute

    // Declaring a Location Manager
    protected LocationManager locationManager;

    public GPSTracker(Context context) {
        this.mContext = context;
        getLocation();
    }

    public Location getLocation() {
        try {
            locationManager = (LocationManager) mContext
                    .getSystemService(LOCATION_SERVICE);

            // Getting GPS status
            isGPSEnabled = locationManager
                    .isProviderEnabled(LocationManager.GPS_PROVIDER);

            // Getting network status
            isNetworkEnabled = locationManager
                    .isProviderEnabled(LocationManager.NETWORK_PROVIDER);

            if (!isGPSEnabled && !isNetworkEnabled) {
                // No network provider is enabled
            } else {
                this.canGetLocation = true;
                if (isNetworkEnabled) {
                    locationManager.requestLocationUpdates(
                            LocationManager.NETWORK_PROVIDER,
                            MIN_TIME_BW_UPDATES,
                            MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                    Log.d("Network", "Network");
                    if (locationManager != null) {
                        location = locationManager
                                .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
                        if (location != null) {
                            latitude = location.getLatitude();
                            longitude = location.getLongitude();
                        }
                    }
                }
                // If GPS enabled, get latitude/longitude using GPS Services
                if (isGPSEnabled) {
                    if (location == null) {
                        locationManager.requestLocationUpdates(
                                LocationManager.GPS_PROVIDER,
                                MIN_TIME_BW_UPDATES,
                                MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                        Log.d("GPS Enabled", "GPS Enabled");
                        if (locationManager != null) {
                            location = locationManager
                                    .getLastKnownLocation(LocationManager.GPS_PROVIDER);
                            if (location != null) {
                                latitude = location.getLatitude();
                                longitude = location.getLongitude();
                            }
                        }
                    }
                }
            }
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        return location;
    }


    /**
     * Stop using GPS listener
     * Calling this function will stop using GPS in your app.
     * */
    public void stopUsingGPS(){
        if(locationManager != null){
            locationManager.removeUpdates(GPSTracker.this);
        }
    }


    /**
     * Function to get latitude
     * */
    public double getLatitude(){
        if(location != null){
            latitude = location.getLatitude();
        }

        // return latitude
        return latitude;
    }


    /**
     * Function to get longitude
     * */
    public double getLongitude(){
        if(location != null){
            longitude = location.getLongitude();
        }

        // return longitude
        return longitude;
    }

    /**
     * Function to check GPS/Wi-Fi enabled
     * @return boolean
     * */
    public boolean canGetLocation() {
        return this.canGetLocation;
    }


    /**
     * Function to show settings alert dialog.
     * On pressing the Settings button it will launch Settings Options.
     * */
    public void showSettingsAlert(){
        AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);

        // Setting Dialog Title
        alertDialog.setTitle("GPS is settings");

        // Setting Dialog Message
        alertDialog.setMessage("GPS is not enabled. Do you want to go to settings menu?");

        // On pressing the Settings button.
        alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog,int which) {
                Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
                mContext.startActivity(intent);
            }
        });

        // On pressing the cancel button
        alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int which) {
            dialog.cancel();
            }
        });

        // Showing Alert Message
        alertDialog.show();
    }


    @Override
    public void onLocationChanged(Location location) {
    }


    @Override
    public void onProviderDisabled(String provider) {
    }


    @Override
    public void onProviderEnabled(String provider) {
    }


    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {
    }


    @Override
    public IBinder onBind(Intent arg0) {
        return null;
    }
}

Activity -AndroidGPSTrackingActivity.java

    public class AndroidGPSTrackingActivity extends Activity {

    Button btnShowLocation;

    // GPSTracker class
    GPSTracker gps;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        btnShowLocation = (Button) findViewById(R.id.btnShowLocation);

        // Show location button click event
        btnShowLocation.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // Create class object
                gps = new GPSTracker(AndroidGPSTrackingActivity.this);

                // Check if GPS enabled
                if(gps.canGetLocation()) {

                    double latitude = gps.getLatitude();
                    double longitude = gps.getLongitude();

                    // \n is for new line
                    Toast.makeText(getApplicationContext(), "Your Location is - \nLat: " + latitude + "\nLong: " + longitude, Toast.LENGTH_LONG).show();
                } else {
                    // Can't get location.
                    // GPS or network is not enabled.
                    // Ask user to enable GPS/network in settings.
                    gps.showSettingsAlert();
                }
            }
        });
    }
}

Layout- main.xml

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

    <Button android:id="@+id/btnShowLocation"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Show Location"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true"/>
</RelativeLayout>

AndroidManifest.xml

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

Best way to get user GPS location in background in Android

You can archive it with a Service and Alarm Manager, but be careful with this, because if you setup a high priority you gonna drain the battery of the phone, in other hand, you really need notify the location every minute? This is because the only way to see a considerably change of the user location, it's traveling in a car or train. I only ask, because that gonna depend of you app and the requirement of the tracking.

Smooth GPS data

I have transformed the Java code from @Stochastically to Kotlin

class KalmanLatLong
{
    private val MinAccuracy: Float = 1f

    private var Q_metres_per_second: Float = 0f
    private var TimeStamp_milliseconds: Long = 0
    private var lat: Double = 0.toDouble()
    private var lng: Double = 0.toDouble()
    private var variance: Float =
        0.toFloat() // P matrix.  Negative means object uninitialised.  NB: units irrelevant, as long as same units used throughout

    fun KalmanLatLong(Q_metres_per_second: Float)
    {
        this.Q_metres_per_second = Q_metres_per_second
        variance = -1f
    }

    fun get_TimeStamp(): Long { return TimeStamp_milliseconds }
    fun get_lat(): Double { return lat }
    fun get_lng(): Double { return lng }
    fun get_accuracy(): Float { return Math.sqrt(variance.toDouble()).toFloat() }

    fun SetState(lat: Double, lng: Double, accuracy: Float, TimeStamp_milliseconds: Long)
    {
        this.lat = lat
        this.lng = lng
        variance = accuracy * accuracy
        this.TimeStamp_milliseconds = TimeStamp_milliseconds
    }

    /// <summary>
    /// Kalman filter processing for lattitude and longitude
    /// https://stackoverflow.com/questions/1134579/smooth-gps-data/15657798#15657798
    /// </summary>
    /// <param name="lat_measurement_degrees">new measurement of lattidude</param>
    /// <param name="lng_measurement">new measurement of longitude</param>
    /// <param name="accuracy">measurement of 1 standard deviation error in metres</param>
    /// <param name="TimeStamp_milliseconds">time of measurement</param>
    /// <returns>new state</returns>
    fun Process(lat_measurement: Double, lng_measurement: Double, accuracy: Float, TimeStamp_milliseconds: Long)
    {
        var accuracy = accuracy
        if (accuracy < MinAccuracy) accuracy = MinAccuracy

        if (variance < 0)
        {
            // if variance < 0, object is unitialised, so initialise with current values
            this.TimeStamp_milliseconds = TimeStamp_milliseconds
            lat = lat_measurement
            lng = lng_measurement
            variance = accuracy * accuracy
        }
        else
        {
            // else apply Kalman filter methodology

            val TimeInc_milliseconds = TimeStamp_milliseconds - this.TimeStamp_milliseconds

            if (TimeInc_milliseconds > 0)
            {
                // time has moved on, so the uncertainty in the current position increases
                variance += TimeInc_milliseconds.toFloat() * Q_metres_per_second * Q_metres_per_second / 1000
                this.TimeStamp_milliseconds = TimeStamp_milliseconds
                // TO DO: USE VELOCITY INFORMATION HERE TO GET A BETTER ESTIMATE OF CURRENT POSITION
            }

            // Kalman gain matrix K = Covarariance * Inverse(Covariance + MeasurementVariance)
            // NB: because K is dimensionless, it doesn't matter that variance has different units to lat and lng
            val K = variance / (variance + accuracy * accuracy)
            // apply K
            lat += K * (lat_measurement - lat)
            lng += K * (lng_measurement - lng)
            // new Covarariance  matrix is (IdentityMatrix - K) * Covarariance
            variance = (1 - K) * variance
        }
    }
}

How can I check the current status of the GPS receiver?

After a few years of working with GPS on windows mobile, I realized that the concept of "losing" a GPS fix can be subjective. To simply listen to what the GPS tells you, adding a NMEAListener and parsing the sentence will tell you whether the fix was "valid" or not. See http://www.gpsinformation.org/dale/nmea.htm#GGA . Unfortunately with some GPSes this value will fluctuate back and forth even during the normal course of operation in a "good fix" area.

So, the other solution is to compare the UTC time of the GPS location against the phone's time (converted to UTC). If they are a certain time difference apart, you can assume you lost the GPS position.

Create an Android GPS tracking application

The source code for the Android mobile application open-gpstracker which you appreciated is available here.

You can checkout the code using SVN client application or via Git:

Debugging the source code will surely help you.

Is Android using NTP to sync time?

i wanted to ask if Android Devices uses the network time protocol (ntp) to synchronize the time.

For general time synchronization, devices with telephony capability, where the wireless provider provides NITZ information, will use NITZ. My understanding is that NTP is used in other circumstances: NITZ-free wireless providers, WiFi-only, etc.

Your cited blog post suggests another circumstance: on-demand time synchronization in support of GPS. That is certainly conceivable, though I do not know whether it is used or not.

Haversine Formula in Python (Bearing and Distance between two GPS points)

Refer to this link :https://gis.stackexchange.com/questions/84885/whats-the-difference-between-vincenty-and-great-circle-distance-calculations

this actually gives two ways of getting distance. They are Haversine and Vincentys. From my research I came to know that Vincentys is relatively accurate. Also use import statement to make the implementation.

How to mock location on device?

There are apps available in the Android Market that allow you to specify a "Mock GPS Location" for your device.

I searched https://market.android.com and found an app called "My Fake Location" that works for me.

The Mock GPS Provider mentioned by Paul above (at http://www.cowlumbus.nl/forum/MockGpsProvider.zip) is another example that includes source code -- although I wasn't able to install the provided APK (it says Failure [INSTALL_FAILED_OLDER_SDK] and may just need a recompile)

In order to use GPS mock locations you need to enable it in your device settings. Go to Settings -> Applications -> Development and check "Allow mock locations"

You can then use an app like the ones described above to set GPS coordinates and Google maps and other apps will use the mock GPS location you specify.

How can I enable or disable the GPS programmatically on Android?

This code works on ROOTED phones:

public class MainActivity extends AppCompatActivity {

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

        String[] cmds = {"cd /system/bin" ,"settings put secure location_providers_allowed +gps"};
        try {
            Process p = Runtime.getRuntime().exec("su");
            DataOutputStream os = new DataOutputStream(p.getOutputStream());
            for (String tmpCmd : cmds) {
                os.writeBytes(tmpCmd + "\n");
            }
            os.writeBytes("exit\n");
            os.flush();
        }
        catch (IOException e){
            e.printStackTrace();
        }
    }
}

For turning off GPS you can use this command instead

settings put secure location_providers_allowed -gps

You can also toggle network accuracy using the following commands: for turning on use:

settings put secure location_providers_allowed +network

and for turning off you can use:

settings put secure location_providers_allowed -network

Disable / Check for Mock Location (prevent gps spoofing)

I have done some investigation and sharing my results here,this may be useful for others.

First, we can check whether MockSetting option is turned ON

public static boolean isMockSettingsON(Context context) {
    // returns true if mock location enabled, false if not enabled.
    if (Settings.Secure.getString(context.getContentResolver(),
                                Settings.Secure.ALLOW_MOCK_LOCATION).equals("0"))
        return false;
    else
        return true;
}

Second, we can check whether are there other apps in the device, which are using android.permission.ACCESS_MOCK_LOCATION (Location Spoofing Apps)

public static boolean areThereMockPermissionApps(Context context) {
    int count = 0;

    PackageManager pm = context.getPackageManager();
    List<ApplicationInfo> packages =
        pm.getInstalledApplications(PackageManager.GET_META_DATA);

    for (ApplicationInfo applicationInfo : packages) {
        try {
            PackageInfo packageInfo = pm.getPackageInfo(applicationInfo.packageName,
                                                        PackageManager.GET_PERMISSIONS);

            // Get Permissions
            String[] requestedPermissions = packageInfo.requestedPermissions;

            if (requestedPermissions != null) {
                for (int i = 0; i < requestedPermissions.length; i++) {
                    if (requestedPermissions[i]
                        .equals("android.permission.ACCESS_MOCK_LOCATION")
                        && !applicationInfo.packageName.equals(context.getPackageName())) {
                        count++;
                    }
                }
            }
        } catch (NameNotFoundException e) {
            Log.e("Got exception " , e.getMessage());
        }
    }

    if (count > 0)
        return true;
    return false;
}

If both above methods, first and second are true, then there are good chances that location may be spoofed or fake.

Now, spoofing can be avoided by using Location Manager's API.

We can remove the test provider before requesting the location updates from both the providers (Network and GPS)

LocationManager lm = (LocationManager) getSystemService(LOCATION_SERVICE);

try {
    Log.d(TAG ,"Removing Test providers")
    lm.removeTestProvider(LocationManager.GPS_PROVIDER);
} catch (IllegalArgumentException error) {
    Log.d(TAG,"Got exception in removing test  provider");
}

lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 0, locationListener);

I have seen that removeTestProvider(~) works very well over Jelly Bean and onwards version. This API appeared to be unreliable till Ice Cream Sandwich.

Flutter Update: Use Geolocator and check Position object's isMocked property.

ACCESS_FINE_LOCATION AndroidManifest Permissions Not Being Granted

You misspelled permission

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

Get GPS location via a service in Android

Here is my solution

Step1 Register Serice in manifest

<receiver
    android:name=".MySMSBroadcastReceiver"
    android:exported="true">
    <intent-filter>
        <action android:name="com.google.android.gms.auth.api.phone.SMS_RETRIEVED" />
    </intent-filter>
</receiver>

Step2 Code Of Service

public class FusedLocationService extends Service {

    private String mLastUpdateTime = null;

    // bunch of location related apis
    private FusedLocationProviderClient mFusedLocationClient;
    private SettingsClient mSettingsClient;
    private LocationRequest mLocationRequest;
    private LocationSettingsRequest mLocationSettingsRequest;
    private LocationCallback mLocationCallback;
    private Location lastLocation;

    // location updates interval - 10sec
    private static final long UPDATE_INTERVAL_IN_MILLISECONDS = 5000;

    // fastest updates interval - 5 sec
    // location updates will be received if another app is requesting the locations
    // than your app can handle
    private static final long FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS = 500;
    private DatabaseReference locationRef;
    private int notificationBuilder = 0;
    private boolean isInitRef;

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.log("LOCATION GET DURATION", "start in service");
        init();
        return START_STICKY;
    }

    /**
     * Initilize Location Apis
     * Create Builder if Share location true
     */
    private void init() {
        mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
        mSettingsClient = LocationServices.getSettingsClient(this);
        mLocationCallback = new LocationCallback() {
            @Override
            public void onLocationResult(LocationResult locationResult) {
                super.onLocationResult(locationResult);
                receiveLocation(locationResult);
            }
        };

        mLocationRequest = new LocationRequest();
        mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
        mLocationRequest.setFastestInterval(FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS);
        mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);

        LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder();
        builder.addLocationRequest(mLocationRequest);
        mLocationSettingsRequest = builder.build();
        startLocationUpdates();
    }

    /**
     * Request Location Update
     */
    @SuppressLint("MissingPermission")
    private void startLocationUpdates() {
        mSettingsClient
                .checkLocationSettings(mLocationSettingsRequest)
                .addOnSuccessListener(locationSettingsResponse -> {
                    Log.log(TAG, "All location settings are satisfied. No MissingPermission");

                    //noinspection MissingPermission
                    mFusedLocationClient.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper());
                })
                .addOnFailureListener(e -> {
                    int statusCode = ((ApiException) e).getStatusCode();
                    switch (statusCode) {
                        case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
                            Log.loge("Location settings are not satisfied. Attempting to upgrade " + "location settings ");
                            break;
                        case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                            Log.loge("Location settings are inadequate, and cannot be " + "fixed here. Fix in Settings.");
                    }
                });
    }

    /**
     * onLocationResult
     * on Receive Location  share to other activity and save if save true
     *
     * @param locationResult
     */
    private void receiveLocation(LocationResult locationResult) {
        lastLocation = locationResult.getLastLocation();

        LocationInstance.getInstance().changeState(lastLocation);

        saveLocation();
    }

    private void saveLocation() {
        String saveLocation = getsaveLocationStatus(this);

        if (saveLocation.equalsIgnoreCase("true") && notificationBuilder == 0) {
            notificationBuilder();
            notificationBuilder = 1;
        } else if (saveLocation.equalsIgnoreCase("false") && notificationBuilder == 1) {
            ((NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE)).cancel(1);
            notificationBuilder = 0;
        }

        Log.logd("receiveLocation : Share :- " + saveLocation + ", [Lat " + lastLocation.getLatitude() + ", Lng" + lastLocation.getLongitude() + "], Time :- " + mLastUpdateTime);

        if (saveLocation.equalsIgnoreCase("true") || getPreviousMin() < getCurrentMin()) {
            setLatLng(this, lastLocation);

            mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());

            if (isOnline(this) && !getUserId(this).equalsIgnoreCase("")) {
                if (!isInitRef) {
                    locationRef = getFirebaseInstance().child(getUserId(this)).child("location");
                    isInitRef = true;
                }
                if (isInitRef) {
                    locationRef.setValue(new LocationModel(lastLocation.getLatitude(), lastLocation.getLongitude(), mLastUpdateTime));
                }
            }
        }
    }

    private int getPreviousMin() {
        int previous_min = 0;
        if (mLastUpdateTime != null) {
            String[] pretime = mLastUpdateTime.split(":");
            previous_min = Integer.parseInt(pretime[1].trim()) + 1;

            if (previous_min > 59) {
                previous_min = 0;
            }
        }
        return previous_min;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        stopLocationUpdates();
    }

    /**
     * Remove Location Update
     */
    public void stopLocationUpdates() {
        mFusedLocationClient
                .removeLocationUpdates(mLocationCallback)
                .addOnCompleteListener(task -> Log.logd("stopLocationUpdates : "));
    }

    private void notificationBuilder() {
        if (Build.VERSION.SDK_INT >= 26) {
            String CHANNEL_ID = "my_channel_01";
            NotificationChannel channel = new NotificationChannel(CHANNEL_ID, "Channel human readable title",
                    NotificationManager.IMPORTANCE_DEFAULT);

            ((NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE)).createNotificationChannel(channel);

            Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID)
                    .setContentTitle("")
                    .setContentText("").build();

            startForeground(1, notification);
        }
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
}

Step 3

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />

Step 4

implementation 'com.google.android.gms:play-services-location:16.0.0'

Java Programming: call an exe from Java and passing parameters

Pass your arguments in constructor itself.

Process process = new ProcessBuilder("C:\\PathToExe\\MyExe.exe","param1","param2").start();

Could not load file or assembly "Oracle.DataAccess" or one of its dependencies

I needed a 64-bit version of oracle.dataaccess.dll but this caused problems with other libraries I was using.

[BadImageFormatException: Could not load file or assembly 'Oracle.DataAccess' or one of its dependencies. An attempt was made to load a program with an incorrect format.]

I followed several steps above. Going to advance settings on the projects pool to toggle allow 32bit worked but I wasn't content to leave it like that so i turned it back on.

My project also had references that relied on Elmah and log4net references. I downloaded the latest version of these and my project was able to build and run fine without messing with the pools's allow 32bit setting.

Standardize data columns in R

I have to assume you meant to say that you wanted a mean of 0 and a standard deviation of 1. If your data is in a dataframe and all the columns are numeric you can simply call the scale function on the data to do what you want.

dat <- data.frame(x = rnorm(10, 30, .2), y = runif(10, 3, 5))
scaled.dat <- scale(dat)

# check that we get mean of 0 and sd of 1
colMeans(scaled.dat)  # faster version of apply(scaled.dat, 2, mean)
apply(scaled.dat, 2, sd)

Using built in functions is classy. Like this cat:

enter image description here

intellij idea - Error: java: invalid source release 1.9

In Project Structure in Project SDK: modify SDK to 11 or higher and in Project language level: modify to 11 - Local variable syntax for lambda parameters

Init function in javascript and how it works

Its is called immediatly invoking function expression (IIFE). Mainly associated with the JavaScript closure concept. Main use is to run the function before the global variable changed, so that the expected behaviour of code can be retained.

Best way to detect when a user leaves a web page?

Thanks to Service Workers, it is possible to implement a solution similar to Adam's purely on the client-side, granted the browser supports it. Just circumvent heartbeat requests:

// The delay should be longer than the heartbeat by a significant enough amount that there won't be false positives
const liveTimeoutDelay = 10000
let liveTimeout = null

global.self.addEventListener('fetch', event => {
  clearTimeout(liveTimeout)
  liveTimeout = setTimeout(() => {
    console.log('User left page')
    // handle page leave
  }, liveTimeoutDelay)
  // Forward any events except for hearbeat events
  if (event.request.url.endsWith('/heartbeat')) {
    event.respondWith(
      new global.Response('Still here')
    )
  }
})

"You tried to execute a query that does not include the specified aggregate function"

I had a similar problem in a MS-Access query, and I solved it by changing my equivalent fName to an "Expression" (as opposed to "Group By" or "Sum"). So long as all of my fields were "Expression", the Access query builder did not require any Group By clause at the end.enter image description here

Eclipse fonts and background color

Background color of views (navigator, console, tasks etc) is set according to the desktop (system) settings. On Linux/GNome I changed System/Preferences/Appeareance to change this color.

Editor colors are set chaotically by different editors, search for background in eclipse preferences to find different options. One easy way to get beautiful dark (and not only dark) themes is to install Afae plugin, and then pick theme within its preferences (twilight theme is beautiful, for example) - again, eclipse prefs, Afae group. Of course this applies only when you edit with Afae.

Convert INT to DATETIME (SQL)

you need to convert to char first because converting to int adds those days to 1900-01-01

select CONVERT (datetime,convert(char(8),rnwl_efctv_dt ))

here are some examples

select CONVERT (datetime,5)

1900-01-06 00:00:00.000

select CONVERT (datetime,20100101)

blows up, because you can't add 20100101 days to 1900-01-01..you go above the limit

convert to char first

declare @i int
select @i = 20100101
select CONVERT (datetime,convert(char(8),@i))

How to write :hover using inline style?

Not gonna happen with CSS only

Inline javascript

<a href='index.html' 
    onmouseover='this.style.textDecoration="none"' 
    onmouseout='this.style.textDecoration="underline"'>
    Click Me
</a>

In a working draft of the CSS2 spec it was declared that you could use pseudo-classes inline like this:

<a href="http://www.w3.org/Style/CSS"
   style="{color: blue; background: white}  /* a+=0 b+=0 c+=0 */
      :visited {color: green}           /* a+=0 b+=1 c+=0 */
      :hover {background: yellow}       /* a+=0 b+=1 c+=0 */
      :visited:hover {color: purple}    /* a+=0 b+=2 c+=0 */
     ">
</a>

but it was never implemented in the release of the spec as far as I know.

http://www.w3.org/TR/2002/WD-css-style-attr-20020515#pseudo-rules

Calendar Recurring/Repeating Events - Best Storage Method

@Rogue Coder

This is great!

You could simply use the modulo operation (MOD or % in mysql) to make your code simple at the end:

Instead of:

AND (
    ( CASE ( 1299132000 - EM1.`meta_value` )
        WHEN 0
          THEN 1
        ELSE ( 1299132000 - EM1.`meta_value` )
      END
    ) / EM2.`meta_value`
) = 1

Do:

$current_timestamp = 1299132000 ;

AND ( ('$current_timestamp' - EM1.`meta_value` ) MOD EM2.`meta_value`) = 1")

To take this further, one could include events that do not recur for ever.

Something like "repeat_interval_1_end" to denote the date of the last "repeat_interval_1" could be added. This however, makes the query more complicated and I can't really figure out how to do this ...

Maybe someone could help!

What is the purpose of .PHONY in a Makefile?

Let's assume you have install target, which is a very common in makefiles. If you do not use .PHONY, and a file named install exists in the same directory as the Makefile, then make install will do nothing. This is because Make interprets the rule to mean "execute such-and-such recipe to create the file named install". Since the file is already there, and its dependencies didn't change, nothing will be done.

However if you make the install target PHONY, it will tell the make tool that the target is fictional, and that make should not expect it to create the actual file. Hence it will not check whether the install file exists, meaning: a) its behavior will not be altered if the file does exist and b) extra stat() will not be called.

Generally all targets in your Makefile which do not produce an output file with the same name as the target name should be PHONY. This typically includes all, install, clean, distclean, and so on.

Android: Proper Way to use onBackPressed() with Toast

additionally, you need to dissmis dialog before calling activity.super.onBackPressed(), otherwise you'll get "Activity has leaked.." error.

Example in my case with sweetalerdialog library:

 @Override
    public void onBackPressed() {
        //super.onBackPressed();
        SweetAlertDialog progressDialog = new SweetAlertDialog(this, SweetAlertDialog.WARNING_TYPE);
        progressDialog.setCancelable(false);
        progressDialog.setTitleText("Are you sure you want to exit?");
        progressDialog.setCancelText("No");
        progressDialog.setConfirmText("Yes");
        progressDialog.setCanceledOnTouchOutside(true);
        progressDialog.setConfirmClickListener(new SweetAlertDialog.OnSweetClickListener() {
            @Override
            public void onClick(SweetAlertDialog sweetAlertDialog) {
                sweetAlertDialog.dismiss();
                MainActivity.super.onBackPressed();
            }
        });
        progressDialog.show();
    }

Bootstrap full responsive navbar with logo or brand name text

Just set the height and width where you are adding that logo. I tried and its working fine

Pandas count(distinct) equivalent

Here an approach to have count distinct over multiple columns. Let's have some data:

data = {'CLIENT_CODE':[1,1,2,1,2,2,3],
        'YEAR_MONTH':[201301,201301,201301,201302,201302,201302,201302],
        'PRODUCT_CODE': [100,150,220,400,50,80,100]
       }
table = pd.DataFrame(data)
table

CLIENT_CODE YEAR_MONTH  PRODUCT_CODE
0   1       201301      100
1   1       201301      150
2   2       201301      220
3   1       201302      400
4   2       201302      50
5   2       201302      80
6   3       201302      100

Now, list the columns of interest and use groupby in a slightly modified syntax:

columns = ['YEAR_MONTH', 'PRODUCT_CODE']
table[columns].groupby(table['CLIENT_CODE']).nunique()

We obtain:

YEAR_MONTH  PRODUCT_CODE CLIENT_CODE        
1           2            3
2           2            3
3           1            1

How can I convert a cv::Mat to a gray scale in OpenCv?

Using the C++ API, the function name has slightly changed and it writes now:

#include <opencv2/imgproc/imgproc.hpp>

cv::Mat greyMat, colorMat;
cv::cvtColor(colorMat, greyMat, CV_BGR2GRAY);

The main difficulties are that the function is in the imgproc module (not in the core), and by default cv::Mat are in the Blue Green Red (BGR) order instead of the more common RGB.

OpenCV 3

Starting with OpenCV 3.0, there is yet another convention. Conversion codes are embedded in the namespace cv:: and are prefixed with COLOR. So, the example becomes then:

#include <opencv2/imgproc/imgproc.hpp>

cv::Mat greyMat, colorMat;
cv::cvtColor(colorMat, greyMat, cv::COLOR_BGR2GRAY);

As far as I have seen, the included file path hasn't changed (this is not a typo).

How to match all occurrences of a regex

if you have a regexp with groups:

str="A 54mpl3 string w1th 7 numbers scatter3r ar0und"
re=/(\d+)[m-t]/

you can use String's scan method to find matching groups:

str.scan re
#> [["54"], ["1"], ["3"]]

To find the matching pattern:

str.to_enum(:scan,re).map {$&}
#> ["54m", "1t", "3r"]

MySQL "NOT IN" query

To use IN, you must have a set, use this syntax instead:

SELECT * FROM Table1 WHERE Table1.principal NOT IN (SELECT principal FROM table2)

npm install private github repositories by dependency in package.json

For those of you who came here for public directories, from the npm docs: https://docs.npmjs.com/files/package.json#git-urls-as-dependencies

Git URLs as Dependencies

Git urls can be of the form:

git://github.com/user/project.git#commit-ish
git+ssh://user@hostname:project.git#commit-ish
git+ssh://user@hostname/project.git#commit-ish
git+http://user@hostname/project/blah.git#commit-ish
git+https://user@hostname/project/blah.git#commit-ish

The commit-ish can be any tag, sha, or branch which can be supplied as an argument to git checkout. The default is master.

What is Ad Hoc Query?

An Ad-hoc query is one created to provide a specific recordset from any or multiple merged tables available on the DB server. These queries usually serve a single-use purpose, and may not be necessary to incorporate into any stored procedure to run again in the future.

Ad-hoc scenario: You receive a request for a specific subset of data with a unique set of variables. If there is no pre-written query that can provide the necessary results, you must write an Ad-hoc query to generate the recordset results.

Beyond a single use Ad-hoc query are stored procedures; i.e. queries which are stored within the DB interface tool. These stored procedures can then be executed in sequence within a module or macro to accomplish a predefined task either on demand, on a schedule, or triggered by another event.

Stored Procedure scenario: Every month you need to generate a report from the same set of tables and with the same variables (these variables may be specific predefined values, computed values such as “end of current month”, or a user’s input values). You would created the procedure as an ad-hoc query the first time. After testing the results to ensure accuracy, you may chose to deploy this query. You would then store the query or series of queries in a module or macro to run again as needed.

Get table names using SELECT statement in MySQL

To get the name of all tables use:

SELECT table_name FROM information_schema.tables;

To get the name of the tables from a specific database use:

SELECT table_name FROM information_schema.tables
WHERE table_schema = 'your_database_name';

Now, to answer the original question, use this query:

INSERT INTO table_name
    SELECT table_name FROM information_schema.tables
        WHERE table_schema = 'your_database_name';

For more details see: http://dev.mysql.com/doc/refman/5.0/en/information-schema.html

Test process.env with Jest

In test file:

const APP_PORT = process.env.APP_PORT || 8080;

In the test script of ./package.json:

"scripts": {
   "test": "jest --setupFiles dotenv/config",
 }

In ./env:

APP_PORT=8080

Javascript get object key name

Here is a simple example, it will help you to get object key name.

var obj ={parts:{costPart:1000, salesPart: 2000}}; console.log(Object.keys(obj));

the output would be parts.

How do you echo a 4-digit Unicode character in Bash?

In bash to print a Unicode character to output use \x,\u or \U (first for 2 digit hex, second for 4 digit hex, third for any length)

echo -e '\U1f602'

I you want to assign it to a variable use $'...' syntax

x=$'\U1f602'
echo $x

WPF global exception handler

A complete solution is here

it's explained very nice with sample code. However, be careful that it does not close the application.Add the line Application.Current.Shutdown(); to gracefully close the app.

Should a RESTful 'PUT' operation return something

The HTTP/1.1 spec (section 9.6) discusses the appropriate response/error codes. However it doesn't address the response content.

What would you expect ? A simple HTTP response code (200 etc.) seems straightforward and unambiguous to me.

Callback function for JSONP with jQuery AJAX

$.ajax({
        url: 'http://url.of.my.server/submit',
        dataType: "jsonp",
        jsonp: 'callback',
        jsonpCallback: 'jsonp_callback'
    });

jsonp is the querystring parameter name that is defined to be acceptable by the server while the jsonpCallback is the javascript function name to be executed at the client.
When you use such url:

url: 'http://url.of.my.server/submit?callback=?'

the question mark ? at the end instructs jQuery to generate a random function while the predfined behavior of the autogenerated function will just invoke the callback -the sucess function in this case- passing the json data as a parameter.

$.ajax({
        url: 'http://url.of.my.server/submit?callback=?',
        success: function (data, status) {
            mySurvey.closePopup();
        },
        error: function (xOptions, textStatus) {
            mySurvey.closePopup();
        }
    });


The same goes here if you are using $.getJSON with ? placeholder it will generate a random function while the predfined behavior of the autogenerated function will just invoke the callback:

$.getJSON('http://url.of.my.server/submit?callback=?',function(data){
//process data here
});

How to use LINQ Distinct() with multiple fields

Employee emp1 = new Employee() { ID = 1, Name = "Narendra1", Salary = 11111, Experience = 3, Age = 30 };Employee emp2 = new Employee() { ID = 2, Name = "Narendra2", Salary = 21111, Experience = 10, Age = 38 };
Employee emp3 = new Employee() { ID = 3, Name = "Narendra3", Salary = 31111, Experience = 4, Age = 33 };
Employee emp4 = new Employee() { ID = 3, Name = "Narendra4", Salary = 41111, Experience = 7, Age = 33 };

List<Employee> lstEmployee = new List<Employee>();

lstEmployee.Add(emp1);
lstEmployee.Add(emp2);
lstEmployee.Add(emp3);
lstEmployee.Add(emp4);

var eemmppss=lstEmployee.Select(cc=>new {cc.ID,cc.Age}).Distinct();

How to install bcmath module?

apt repo have this extension, just run the below command from your terminal ::

sudo apt-get install php7.2-bcmath*

How to hide 'Back' button on navigation bar on iPhone?

In Swift:

Add this to the controller

override func viewDidLoad() {
    super.viewDidLoad()
    self.navigationItem.setHidesBackButton(true, animated: false)
}

How can I convert a Timestamp into either Date or DateTime object?

java.sql.Timestamp is a subclass of java.util.Date. So, just upcast it.

Date dtStart = resultSet.getTimestamp("dtStart");
Date dtEnd = resultSet.getTimestamp("dtEnd");

Using SimpleDateFormat and creating Joda DateTime should be straightforward from this point on.

Git - How to close commit editor?

Not sure the key combination that gets you there to the > prompt but it is not a bash prompt that I know. I usually get it by accident. Ctrl+C (or D) gets me back to the $ prompt.

Where can I find documentation on formatting a date in JavaScript?

We can do it manually, its pretty straight and simple.

_x000D_
_x000D_
var today = new Date();_x000D_
    _x000D_
    alert("today :"+today);_x000D_
    _x000D_
    var dd = today.getDate();_x000D_
    alert("dd :"+dd);_x000D_
    _x000D_
    var mm = today.getMonth()+1; //January is 0!_x000D_
    alert("mm :"+mm);_x000D_
    _x000D_
    var yyyy = today.getFullYear();_x000D_
    _x000D_
    alert("yyyy :"+yyyy);_x000D_
    _x000D_
    _x000D_
    var hh = today.getHours();_x000D_
    _x000D_
    alert("hh :"+hh);_x000D_
    _x000D_
    var min = today.getMinutes();_x000D_
    _x000D_
   alert("min :"+min);_x000D_
   _x000D_
   var ss = today.getSeconds();_x000D_
   _x000D_
   alert("ss :"+ss);_x000D_
_x000D_
    if(dd<10) {_x000D_
        dd='0'+dd_x000D_
    } _x000D_
_x000D_
    if(mm<10) {_x000D_
        mm='0'+mm_x000D_
    } _x000D_
_x000D_
  //  today = mm+'/'+dd+'/'+yyyy;_x000D_
    // if you want / instead - then add /_x000D_
  _x000D_
  _x000D_
  today = yyyy + "-" + mm + "-" + dd + " " + hh + ":" + mm + ":" + ss;_x000D_
     today = yyyy + "/" + mm + "/" + dd + " " + hh + ":" + mm + ":" + ss;_x000D_
     // use according to your choice 
_x000D_
_x000D_
_x000D_

Passing functions with arguments to another function in Python?

Here is a way to do it with a closure:

    def generate_add_mult_func(func):
        def function_generator(x):
            return reduce(func,range(1,x))
        return function_generator

    def add(x,y):
        return x+y

    def mult(x,y):
        return x*y

    adding=generate_add_mult_func(add)
    multiplying=generate_add_mult_func(mult)

    print adding(10)
    print multiplying(10)

Create a simple Login page using eclipse and mysql

use this code it is working

// index.jsp or login.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>

<form action="login" method="post">
Username : <input type="text" name="username"><br>
Password : <input type="password" name="pass"><br>
<input type="submit"><br>
</form>

</body>
</html>

// authentication servlet class

    import java.io.IOException;
    import java.io.PrintWriter;
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.SQLException;
    import java.sql.Statement;

    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;

    public class auth extends HttpServlet {
        private static final long serialVersionUID = 1L;

        public auth() {
            super();
        }
        protected void doGet(HttpServletRequest request,
                HttpServletResponse response) throws ServletException, IOException {

        }

        protected void doPost(HttpServletRequest request,
                HttpServletResponse response) throws ServletException, IOException {

            try {
                Class.forName("com.mysql.jdbc.Driver");
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }

            String username = request.getParameter("username");
            String pass = request.getParameter("pass");

            String sql = "select * from reg where username='" + username + "'";
            Connection conn = null;

            try {
                conn = DriverManager.getConnection("jdbc:mysql://localhost/Exam",
                        "root", "");
                Statement s = conn.createStatement();

                java.sql.ResultSet rs = s.executeQuery(sql);
                String un = null;
                String pw = null;
                String name = null;

            /* Need to put some condition in case the above query does not return any row, else code will throw Null Pointer exception */   

            PrintWriter prwr1 = response.getWriter();               
            if(!rs.isBeforeFirst()){
                prwr1.write("<h1> No Such User in Database<h1>");
            } else {

/* Conditions to be executed after at least one row is returned by query execution */ 
                while (rs.next()) {
                    un = rs.getString("username");
                    pw = rs.getString("password");
                    name = rs.getString("name");
                }

                PrintWriter pww = response.getWriter();

                if (un.equalsIgnoreCase(username) && pw.equals(pass)) {
                                // use this or create request dispatcher 
                    response.setContentType("text/html");
                    pww.write("<h1>Welcome, " + name + "</h1>");
                } else {
                    pww.write("wrong username or password\n");
                }
              }

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

        }

    }

How can I pass command-line arguments to a Perl program?

Yet another options is to use perl -s, eg:

#!/usr/bin/perl -s

print "value of -x: $x\n";
print "value of -name: $name\n";

Then call it like this :

% ./myprog -x -name=Jeff
value of -x: 1
value of -name: Jeff

Or see the original article for more details:

How do I completely uninstall Node.js, and reinstall from beginning (Mac OS X)

maybe you need to make

hash -r 

it helps with problem of symlink

$ node -v
$ bash: /opt/local/bin/node: No such file or directory

The type arguments cannot be inferred from the usage. Try specifying the type arguments explicitly

C# compiler have only lambda

arg => arg.MyProperty

for infer type of arg(TModel) an type of arg.MyProperty(TProperty). It's impossible.

How do I define and use an ENUM in Objective-C?

This is how Apple does it for classes like NSString:

In the header file:

enum {
    PlayerStateOff,
    PlayerStatePlaying,
    PlayerStatePaused
};

typedef NSInteger PlayerState;

Refer to Coding Guidelines at http://developer.apple.com/

Check OS version in Swift?

For iOS, try:

var systemVersion = UIDevice.current.systemVersion

For OS X, try:

var systemVersion = NSProcessInfo.processInfo().operatingSystemVersion

If you just want to check if the users is running at least a specific version, you can also use the following Swift 2 feature which works on iOS and OS X:

if #available(iOS 9.0, *) {
    // use the feature only available in iOS 9
    // for ex. UIStackView
} else {
    // or use some work around
}

BUT it is not recommended to check the OS version. It is better to check if the feature you want to use is available on the device than comparing version numbers. For iOS, as mentioned above, you should check if it responds to a selector; eg.:

if (self.respondsToSelector(Selector("showViewController"))) {
    self.showViewController(vc, sender: self)
} else {
    // some work around
}

How to exit from the application and show the home screen?

If you want to end an activity you can simply call finish(). It is however bad practice to have an exit button on the screen.

Get User's Current Location / Coordinates

// its with strongboard 
@IBOutlet weak var mapView: MKMapView!

//12.9767415,77.6903967 - exact location latitude n longitude location 
let cooridinate = CLLocationCoordinate2D(latitude: 12.9767415 , longitude: 77.6903967)
let  spanDegree = MKCoordinateSpan(latitudeDelta: 0.2,longitudeDelta: 0.2)
let region = MKCoordinateRegion(center: cooridinate , span: spanDegree)
mapView.setRegion(region, animated: true)

How to remove the border highlight on an input text element

Use this code:

input:focus {
    outline: 0;
}

View contents of database file in Android Studio

Its a combination from other answers with a plus

  1. Install DB Browser for SQLite
  2. Get the exact location from Device File Explorer for MyBase.db something like "/data/data/com.whatever.myapp/databases/MyBase.db"
  3. Set the project window from Android to Project - so you can see the files (build.gradle, gradle.properties,...etc)
  4. In Project window right click and chose Open in Terminal
  5. In terminal you are now in the root director of your application from the hardisk so execute: adb pull /data/data/com.whatever.myapp/databases/MyBase.db
  6. Now on the Project window of you Android Studio you have a file "MyBase.db"
  7. Double click your db file from Project and you can now browse/edit your databases in DB Browser
  8. When you are ready just do Write Changes in DB Browser so databases are saved on hardisk
  9. In terminal with the command: adb push MyBase.db /data/data/com.whatever.myapp/databases/MyBase.db you just send from the Hardisk to device the edited database.

Gradle task - pass arguments to Java application

You can find the solution in Problems passing system properties and parameters when running Java class via Gradle . Both involve the use of the args property

Also you should read the difference between passing with -D or with -P that is explained in the Gradle documentation

SELECT query with CASE condition and SUM()

Use an "Or"

Select SUM(CAmount) as PaymentAmount 
from TableOrderPayment 
where (CPaymentType='Check' Or CPaymentType='Cash')
   and CDate <= case CPaymentType When 'Check' Then SYSDATETIME() else CDate End
   and CStatus='" & "Active" & "'"

or an "IN"

Select SUM(CAmount) as PaymentAmount 
from TableOrderPayment 
where CPaymentType IN ('Check', 'Cash')
   and CDate <= case CPaymentType When 'Check' Then SYSDATETIME() else CDate End
   and CStatus='" & "Active" & "'"

PowerShell : retrieve JSON object by field value

I just asked the same question here: https://stackoverflow.com/a/23062370/3532136 It has a good solution. I hope it helps ^^. In resume, you can use this:

The Json file in my case was called jsonfile.json:

{
    "CARD_MODEL_TITLE": "OWNER'S MANUAL",
    "CARD_MODEL_SUBTITLE": "Configure your download",
    "CARD_MODEL_SELECT": "Select Model",
    "CARD_LANG_TITLE": "Select Language",
    "CARD_LANG_DEVICE_LANG": "Your device",
    "CARD_YEAR_TITLE": "Select Model Year",
    "CARD_YEAR_LATEST": "(Latest)",
    "STEPS_MODEL": "Model",
    "STEPS_LANGUAGE": "Language",
    "STEPS_YEAR": "Model Year",
    "BUTTON_BACK": "Back",
    "BUTTON_NEXT": "Next",
    "BUTTON_CLOSE": "Close"
}

Code:

$json = (Get-Content "jsonfile.json" -Raw) | ConvertFrom-Json

$json.psobject.properties.name

Output:

CARD_MODEL_TITLE
CARD_MODEL_SUBTITLE
CARD_MODEL_SELECT
CARD_LANG_TITLE
CARD_LANG_DEVICE_LANG
CARD_YEAR_TITLE
CARD_YEAR_LATEST
STEPS_MODEL
STEPS_LANGUAGE
STEPS_YEAR
BUTTON_BACK
BUTTON_NEXT
BUTTON_CLOSE

Thanks to mjolinor.

Python: Remove division decimal

if val % 1 == 0:
    val = int(val)

else:
    val = float(val)

This worked for me.

How it works: if the remainder of the quotient of val and 1 is 0, val has to be an integer and can, therefore, be declared to be int without having to worry about losing decimal numbers.

Compare these two situations:

A:

val = 12.00

if val % 1 == 0:
    val = int(val)
else:
    val = float(val)

print(val)

In this scenario, the output is 12, because 12.00 divided by 1 has the remainder of 0. With this information we know, that val doesn't have any decimals and we can declare val to be int.

B:

val = 13.58

if val % 1 == 0:
    val = int(val)
else:
    val = float(val)

print(val)

This time the output is 13.58, because when val is divided by 1 there is a remainder (0.58) and therefore val is declared to be a float.

By just declaring the number to be an int (without testing the remainder) decimal numbers will be cut off.

This way there are no zeros in the end and no other than the zeros will be ignored.

What is the difference between Html.Hidden and Html.HiddenFor

The Html.Hidden creates a hidden input but you have to specify the name and all the attributes you want to give that field and value. The Html.HiddenFor creates a hidden input for the object that you pass to it, they look like this:

Html.Hidden("yourProperty",model.yourProperty);

Html.HiddenFor(m => m.yourProperty)

In this case the output is the same!

CSS force new line

How about with a :before pseudoelement:

a:before {
  content: '\a';
  white-space: pre;
}

Unsupported major.minor version 52.0 when rendering in Android Studio

Changing to Java SDK to Java 8 worked for me. Android Studio settings: File -> other settings ->Default project structure -> JDK location -> jdk1.8.0_71.jdk/Contents/Home

How to obtain values of request variables using Python and Flask

If you want to retrieve POST data:

first_name = request.form.get("firstname")

If you want to retrieve GET (query string) data:

first_name = request.args.get("firstname")

Or if you don't care/know whether the value is in the query string or in the post data:

first_name = request.values.get("firstname") 

request.values is a CombinedMultiDict that combines Dicts from request.form and request.args.

How to keep the spaces at the end and/or at the beginning of a String?

Even if you use string formatting, sometimes you still need white spaces at the beginning or the end of your string. For these cases, neither escaping with \, nor xml:space attribute helps. You must use HTML entity &#160; for a whitespace.

Use &#160; for non-breakable whitespace.
Use &#032; for regular space.

How to write and read java serialized objects into a file

Simple program to write objects to file and read objects from file.

_x000D_
_x000D_
package program;_x000D_
_x000D_
import java.io.File;_x000D_
import java.io.FileInputStream;_x000D_
import java.io.FileOutputStream;_x000D_
import java.io.ObjectInputStream;_x000D_
import java.io.ObjectOutputStream;_x000D_
import java.io.Serializable;_x000D_
_x000D_
public class TempList {_x000D_
_x000D_
  public static void main(String[] args) throws Exception {_x000D_
    Counter counter = new Counter(10);_x000D_
_x000D_
    File f = new File("MyFile.txt");_x000D_
    FileOutputStream fos = new FileOutputStream(f);_x000D_
    ObjectOutputStream oos = new ObjectOutputStream(fos);_x000D_
    oos.writeObject(counter);_x000D_
    oos.close();_x000D_
_x000D_
    FileInputStream fis = new FileInputStream(f);_x000D_
    ObjectInputStream ois = new ObjectInputStream(fis);_x000D_
    Counter newCounter = (Counter) ois.readObject();_x000D_
    System.out.println(newCounter.count);_x000D_
    ois.close();_x000D_
  }_x000D_
_x000D_
}_x000D_
_x000D_
class Counter implements Serializable {_x000D_
_x000D_
  private static final long serialVersionUID = -628789568975888036 L;_x000D_
_x000D_
  int count;_x000D_
_x000D_
  Counter(int count) {_x000D_
    this.count = count;_x000D_
  }_x000D_
}
_x000D_
_x000D_
_x000D_

After running the program the output in your console window will be 10 and you can find the file inside Test folder by clicking on the icon show in below image.

enter image description here

How to clear a textbox using javascript

Onfous And onblur Text box with javascript

   <input type="text" value="A new value" onfocus="if(this.value=='A new value') this.value='';" onblur="if(this.value=='') this.value='A new value';"/>

Calling Member Functions within Main C++

Declare an instance of MyClass, and then call the member function on that instance:

MyClass m;

m.printInformation();

How to handle a lost KeyStore password in Android?

Android brute force will not work if your both the passwords are different so the best option might be like that try to find the file named as

log.idea

in your C:/users/your named account then you might found that in there in android folder open that file lpg.idea in notepad and then search for

alias

using find option in notepad you will find it that the password and alias and alias passwors has been shown there

Scanner only reads first word instead of line

Use input.nextLine(); instead of input.next();

Passing multiple variables to another page in url

<a href="deleteshare.php?did=<?php echo "$rowc[id]"; ?>&uid=<?php echo "$id";?>">DELETE</a>

Pass multiple Variable one page to another page

Correct way to detach from a container without stopping it

If you do "docker attach "container id" you get into the container. To exit from the container without stopping the container you need to enter Ctrl+P+Q

Java Replacing multiple different substring in a string at once (or in the most efficient way)

Check this:

String.format(str,STR[])

For instance:

String.format( "Put your %s where your %s is", "money", "mouth" );

What are the lengths of Location Coordinates, latitude and longitude?

Google Maps actually uses signed values to represent the position:

  • Latitude : max/min 90.0000000 to -90.0000000

  • Longitude : max/min 180.0000000 to -180.0000000

So if you want to work with Coordinates in your projects you would need DECIMAL(10,7) ie. for SQL.

Class JavaLaunchHelper is implemented in both ... libinstrument.dylib. One of the two will be used. Which one is undefined

Copy Pasting @Lichtamberg's comments to gotoalberto's answer

Works also for Java 1.8:

# in ~/.zshrc and ~/.bashrc

export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.8.0_92.jdk/Contents/Home 
export PATH=$JAVA_HOME/bin:$PATH 

This fixed my issue on java 8.

Python circular importing?

I was able to import the module within the function (only) that would require the objects from this module:

def my_func():
    import Foo
    foo_instance = Foo()

You need to use a Theme.AppCompat theme (or descendant) with this activity

Change the theme of the desired Activity. This works for me:

<activity
            android:name="HomeActivity"
            android:screenOrientation="landscape"
            android:theme="@style/Theme.AppCompat.Light"
            android:windowSoftInputMode="stateHidden" />

When is the init() function run?

Take for example a framework or a library you're designing for other users, these users eventually will have a main function in their code in order to execute their app. If the user directly imports a sub-package of your library's project then the init of that sub-package will be called(once) first of all. The same for the root package of the library, etc...

There are many times when you may want a code block to be executed without the existence of a main func, directly or not.

If you, as the developer of the imaginary library, import your library's sub-package that has an init function, it will be called first and once, you don't have a main func but you need to make sure that some variables, or a table, will be initialized before the calls of other functions.

A good thing to remember and not to worry about, is that: the init always execute once per application.

init execution happens:

  1. right before the init function of the "caller" package,
  2. before the, optionally, main func,
  3. but after the package-level variables, var = [...] or cost = [...],

When you import a package it will run all of its init functions, by order.

I'll will give a very good example of an init function. It will add mime types to a standard go's library named mime and a package-level function will use the mime standard package directly to get the custom mime types that are already be initialized at its init function:

package mime

import (
    "mime"
    "path/filepath"
)

var types = map[string]string{
    ".3dm":       "x-world/x-3dmf",
    ".3dmf":      "x-world/x-3dmf",
    ".7z":        "application/x-7z-compressed",
    ".a":         "application/octet-stream",
    ".aab":       "application/x-authorware-bin",
    ".aam":       "application/x-authorware-map",
    ".aas":       "application/x-authorware-seg",
    ".abc":       "text/vndabc",
    ".ace":       "application/x-ace-compressed",
    ".acgi":      "text/html",
    ".afl":       "video/animaflex",
    ".ai":        "application/postscript",
    ".aif":       "audio/aiff",
    ".aifc":      "audio/aiff",
    ".aiff":      "audio/aiff",
    ".aim":       "application/x-aim",
    ".aip":       "text/x-audiosoft-intra",
    ".alz":       "application/x-alz-compressed",
    ".ani":       "application/x-navi-animation",
    ".aos":       "application/x-nokia-9000-communicator-add-on-software",
    ".aps":       "application/mime",
    ".apk":       "application/vnd.android.package-archive",
    ".arc":       "application/x-arc-compressed",
    ".arj":       "application/arj",
    ".art":       "image/x-jg",
    ".asf":       "video/x-ms-asf",
    ".asm":       "text/x-asm",
    ".asp":       "text/asp",
    ".asx":       "application/x-mplayer2",
    ".au":        "audio/basic",
    ".avi":       "video/x-msvideo",
    ".avs":       "video/avs-video",
    ".bcpio":     "application/x-bcpio",
    ".bin":       "application/mac-binary",
    ".bmp":       "image/bmp",
    ".boo":       "application/book",
    ".book":      "application/book",
    ".boz":       "application/x-bzip2",
    ".bsh":       "application/x-bsh",
    ".bz2":       "application/x-bzip2",
    ".bz":        "application/x-bzip",
    ".c++":       "text/plain",
    ".c":         "text/x-c",
    ".cab":       "application/vnd.ms-cab-compressed",
    ".cat":       "application/vndms-pkiseccat",
    ".cc":        "text/x-c",
    ".ccad":      "application/clariscad",
    ".cco":       "application/x-cocoa",
    ".cdf":       "application/cdf",
    ".cer":       "application/pkix-cert",
    ".cha":       "application/x-chat",
    ".chat":      "application/x-chat",
    ".chrt":      "application/vnd.kde.kchart",
    ".class":     "application/java",
    ".com":       "text/plain",
    ".conf":      "text/plain",
    ".cpio":      "application/x-cpio",
    ".cpp":       "text/x-c",
    ".cpt":       "application/mac-compactpro",
    ".crl":       "application/pkcs-crl",
    ".crt":       "application/pkix-cert",
    ".crx":       "application/x-chrome-extension",
    ".csh":       "text/x-scriptcsh",
    ".css":       "text/css",
    ".csv":       "text/csv",
    ".cxx":       "text/plain",
    ".dar":       "application/x-dar",
    ".dcr":       "application/x-director",
    ".deb":       "application/x-debian-package",
    ".deepv":     "application/x-deepv",
    ".def":       "text/plain",
    ".der":       "application/x-x509-ca-cert",
    ".dif":       "video/x-dv",
    ".dir":       "application/x-director",
    ".divx":      "video/divx",
    ".dl":        "video/dl",
    ".dmg":       "application/x-apple-diskimage",
    ".doc":       "application/msword",
    ".dot":       "application/msword",
    ".dp":        "application/commonground",
    ".drw":       "application/drafting",
    ".dump":      "application/octet-stream",
    ".dv":        "video/x-dv",
    ".dvi":       "application/x-dvi",
    ".dwf":       "drawing/x-dwf=(old)",
    ".dwg":       "application/acad",
    ".dxf":       "application/dxf",
    ".dxr":       "application/x-director",
    ".el":        "text/x-scriptelisp",
    ".elc":       "application/x-bytecodeelisp=(compiled=elisp)",
    ".eml":       "message/rfc822",
    ".env":       "application/x-envoy",
    ".eps":       "application/postscript",
    ".es":        "application/x-esrehber",
    ".etx":       "text/x-setext",
    ".evy":       "application/envoy",
    ".exe":       "application/octet-stream",
    ".f77":       "text/x-fortran",
    ".f90":       "text/x-fortran",
    ".f":         "text/x-fortran",
    ".fdf":       "application/vndfdf",
    ".fif":       "application/fractals",
    ".fli":       "video/fli",
    ".flo":       "image/florian",
    ".flv":       "video/x-flv",
    ".flx":       "text/vndfmiflexstor",
    ".fmf":       "video/x-atomic3d-feature",
    ".for":       "text/x-fortran",
    ".fpx":       "image/vndfpx",
    ".frl":       "application/freeloader",
    ".funk":      "audio/make",
    ".g3":        "image/g3fax",
    ".g":         "text/plain",
    ".gif":       "image/gif",
    ".gl":        "video/gl",
    ".gsd":       "audio/x-gsm",
    ".gsm":       "audio/x-gsm",
    ".gsp":       "application/x-gsp",
    ".gss":       "application/x-gss",
    ".gtar":      "application/x-gtar",
    ".gz":        "application/x-compressed",
    ".gzip":      "application/x-gzip",
    ".h":         "text/x-h",
    ".hdf":       "application/x-hdf",
    ".help":      "application/x-helpfile",
    ".hgl":       "application/vndhp-hpgl",
    ".hh":        "text/x-h",
    ".hlb":       "text/x-script",
    ".hlp":       "application/hlp",
    ".hpg":       "application/vndhp-hpgl",
    ".hpgl":      "application/vndhp-hpgl",
    ".hqx":       "application/binhex",
    ".hta":       "application/hta",
    ".htc":       "text/x-component",
    ".htm":       "text/html",
    ".html":      "text/html",
    ".htmls":     "text/html",
    ".htt":       "text/webviewhtml",
    ".htx":       "text/html",
    ".ice":       "x-conference/x-cooltalk",
    ".ico":       "image/x-icon",
    ".ics":       "text/calendar",
    ".icz":       "text/calendar",
    ".idc":       "text/plain",
    ".ief":       "image/ief",
    ".iefs":      "image/ief",
    ".iges":      "application/iges",
    ".igs":       "application/iges",
    ".ima":       "application/x-ima",
    ".imap":      "application/x-httpd-imap",
    ".inf":       "application/inf",
    ".ins":       "application/x-internett-signup",
    ".ip":        "application/x-ip2",
    ".isu":       "video/x-isvideo",
    ".it":        "audio/it",
    ".iv":        "application/x-inventor",
    ".ivr":       "i-world/i-vrml",
    ".ivy":       "application/x-livescreen",
    ".jam":       "audio/x-jam",
    ".jav":       "text/x-java-source",
    ".java":      "text/x-java-source",
    ".jcm":       "application/x-java-commerce",
    ".jfif-tbnl": "image/jpeg",
    ".jfif":      "image/jpeg",
    ".jnlp":      "application/x-java-jnlp-file",
    ".jpe":       "image/jpeg",
    ".jpeg":      "image/jpeg",
    ".jpg":       "image/jpeg",
    ".jps":       "image/x-jps",
    ".js":        "application/javascript",
    ".json":      "application/json",
    ".jut":       "image/jutvision",
    ".kar":       "audio/midi",
    ".karbon":    "application/vnd.kde.karbon",
    ".kfo":       "application/vnd.kde.kformula",
    ".flw":       "application/vnd.kde.kivio",
    ".kml":       "application/vnd.google-earth.kml+xml",
    ".kmz":       "application/vnd.google-earth.kmz",
    ".kon":       "application/vnd.kde.kontour",
    ".kpr":       "application/vnd.kde.kpresenter",
    ".kpt":       "application/vnd.kde.kpresenter",
    ".ksp":       "application/vnd.kde.kspread",
    ".kwd":       "application/vnd.kde.kword",
    ".kwt":       "application/vnd.kde.kword",
    ".ksh":       "text/x-scriptksh",
    ".la":        "audio/nspaudio",
    ".lam":       "audio/x-liveaudio",
    ".latex":     "application/x-latex",
    ".lha":       "application/lha",
    ".lhx":       "application/octet-stream",
    ".list":      "text/plain",
    ".lma":       "audio/nspaudio",
    ".log":       "text/plain",
    ".lsp":       "text/x-scriptlisp",
    ".lst":       "text/plain",
    ".lsx":       "text/x-la-asf",
    ".ltx":       "application/x-latex",
    ".lzh":       "application/octet-stream",
    ".lzx":       "application/lzx",
    ".m1v":       "video/mpeg",
    ".m2a":       "audio/mpeg",
    ".m2v":       "video/mpeg",
    ".m3u":       "audio/x-mpegurl",
    ".m":         "text/x-m",
    ".man":       "application/x-troff-man",
    ".manifest":  "text/cache-manifest",
    ".map":       "application/x-navimap",
    ".mar":       "text/plain",
    ".mbd":       "application/mbedlet",
    ".mc$":       "application/x-magic-cap-package-10",
    ".mcd":       "application/mcad",
    ".mcf":       "text/mcf",
    ".mcp":       "application/netmc",
    ".me":        "application/x-troff-me",
    ".mht":       "message/rfc822",
    ".mhtml":     "message/rfc822",
    ".mid":       "application/x-midi",
    ".midi":      "application/x-midi",
    ".mif":       "application/x-frame",
    ".mime":      "message/rfc822",
    ".mjf":       "audio/x-vndaudioexplosionmjuicemediafile",
    ".mjpg":      "video/x-motion-jpeg",
    ".mm":        "application/base64",
    ".mme":       "application/base64",
    ".mod":       "audio/mod",
    ".moov":      "video/quicktime",
    ".mov":       "video/quicktime",
    ".movie":     "video/x-sgi-movie",
    ".mp2":       "audio/mpeg",
    ".mp3":       "audio/mpeg3",
    ".mp4":       "video/mp4",
    ".mpa":       "audio/mpeg",
    ".mpc":       "application/x-project",
    ".mpe":       "video/mpeg",
    ".mpeg":      "video/mpeg",
    ".mpg":       "video/mpeg",
    ".mpga":      "audio/mpeg",
    ".mpp":       "application/vndms-project",
    ".mpt":       "application/x-project",
    ".mpv":       "application/x-project",
    ".mpx":       "application/x-project",
    ".mrc":       "application/marc",
    ".ms":        "application/x-troff-ms",
    ".mv":        "video/x-sgi-movie",
    ".my":        "audio/make",
    ".mzz":       "application/x-vndaudioexplosionmzz",
    ".nap":       "image/naplps",
    ".naplps":    "image/naplps",
    ".nc":        "application/x-netcdf",
    ".ncm":       "application/vndnokiaconfiguration-message",
    ".nif":       "image/x-niff",
    ".niff":      "image/x-niff",
    ".nix":       "application/x-mix-transfer",
    ".nsc":       "application/x-conference",
    ".nvd":       "application/x-navidoc",
    ".o":         "application/octet-stream",
    ".oda":       "application/oda",
    ".odb":       "application/vnd.oasis.opendocument.database",
    ".odc":       "application/vnd.oasis.opendocument.chart",
    ".odf":       "application/vnd.oasis.opendocument.formula",
    ".odg":       "application/vnd.oasis.opendocument.graphics",
    ".odi":       "application/vnd.oasis.opendocument.image",
    ".odm":       "application/vnd.oasis.opendocument.text-master",
    ".odp":       "application/vnd.oasis.opendocument.presentation",
    ".ods":       "application/vnd.oasis.opendocument.spreadsheet",
    ".odt":       "application/vnd.oasis.opendocument.text",
    ".oga":       "audio/ogg",
    ".ogg":       "audio/ogg",
    ".ogv":       "video/ogg",
    ".omc":       "application/x-omc",
    ".omcd":      "application/x-omcdatamaker",
    ".omcr":      "application/x-omcregerator",
    ".otc":       "application/vnd.oasis.opendocument.chart-template",
    ".otf":       "application/vnd.oasis.opendocument.formula-template",
    ".otg":       "application/vnd.oasis.opendocument.graphics-template",
    ".oth":       "application/vnd.oasis.opendocument.text-web",
    ".oti":       "application/vnd.oasis.opendocument.image-template",
    ".otm":       "application/vnd.oasis.opendocument.text-master",
    ".otp":       "application/vnd.oasis.opendocument.presentation-template",
    ".ots":       "application/vnd.oasis.opendocument.spreadsheet-template",
    ".ott":       "application/vnd.oasis.opendocument.text-template",
    ".p10":       "application/pkcs10",
    ".p12":       "application/pkcs-12",
    ".p7a":       "application/x-pkcs7-signature",
    ".p7c":       "application/pkcs7-mime",
    ".p7m":       "application/pkcs7-mime",
    ".p7r":       "application/x-pkcs7-certreqresp",
    ".p7s":       "application/pkcs7-signature",
    ".p":         "text/x-pascal",
    ".part":      "application/pro_eng",
    ".pas":       "text/pascal",
    ".pbm":       "image/x-portable-bitmap",
    ".pcl":       "application/vndhp-pcl",
    ".pct":       "image/x-pict",
    ".pcx":       "image/x-pcx",
    ".pdb":       "chemical/x-pdb",
    ".pdf":       "application/pdf",
    ".pfunk":     "audio/make",
    ".pgm":       "image/x-portable-graymap",
    ".pic":       "image/pict",
    ".pict":      "image/pict",
    ".pkg":       "application/x-newton-compatible-pkg",
    ".pko":       "application/vndms-pkipko",
    ".pl":        "text/x-scriptperl",
    ".plx":       "application/x-pixclscript",
    ".pm4":       "application/x-pagemaker",
    ".pm5":       "application/x-pagemaker",
    ".pm":        "text/x-scriptperl-module",
    ".png":       "image/png",
    ".pnm":       "application/x-portable-anymap",
    ".pot":       "application/mspowerpoint",
    ".pov":       "model/x-pov",
    ".ppa":       "application/vndms-powerpoint",
    ".ppm":       "image/x-portable-pixmap",
    ".pps":       "application/mspowerpoint",
    ".ppt":       "application/mspowerpoint",
    ".ppz":       "application/mspowerpoint",
    ".pre":       "application/x-freelance",
    ".prt":       "application/pro_eng",
    ".ps":        "application/postscript",
    ".psd":       "application/octet-stream",
    ".pvu":       "paleovu/x-pv",
    ".pwz":       "application/vndms-powerpoint",
    ".py":        "text/x-scriptphyton",
    ".pyc":       "application/x-bytecodepython",
    ".qcp":       "audio/vndqcelp",
    ".qd3":       "x-world/x-3dmf",
    ".qd3d":      "x-world/x-3dmf",
    ".qif":       "image/x-quicktime",
    ".qt":        "video/quicktime",
    ".qtc":       "video/x-qtc",
    ".qti":       "image/x-quicktime",
    ".qtif":      "image/x-quicktime",
    ".ra":        "audio/x-pn-realaudio",
    ".ram":       "audio/x-pn-realaudio",
    ".rar":       "application/x-rar-compressed",
    ".ras":       "application/x-cmu-raster",
    ".rast":      "image/cmu-raster",
    ".rexx":      "text/x-scriptrexx",
    ".rf":        "image/vndrn-realflash",
    ".rgb":       "image/x-rgb",
    ".rm":        "application/vndrn-realmedia",
    ".rmi":       "audio/mid",
    ".rmm":       "audio/x-pn-realaudio",
    ".rmp":       "audio/x-pn-realaudio",
    ".rng":       "application/ringing-tones",
    ".rnx":       "application/vndrn-realplayer",
    ".roff":      "application/x-troff",
    ".rp":        "image/vndrn-realpix",
    ".rpm":       "audio/x-pn-realaudio-plugin",
    ".rt":        "text/vndrn-realtext",
    ".rtf":       "text/richtext",
    ".rtx":       "text/richtext",
    ".rv":        "video/vndrn-realvideo",
    ".s":         "text/x-asm",
    ".s3m":       "audio/s3m",
    ".s7z":       "application/x-7z-compressed",
    ".saveme":    "application/octet-stream",
    ".sbk":       "application/x-tbook",
    ".scm":       "text/x-scriptscheme",
    ".sdml":      "text/plain",
    ".sdp":       "application/sdp",
    ".sdr":       "application/sounder",
    ".sea":       "application/sea",
    ".set":       "application/set",
    ".sgm":       "text/x-sgml",
    ".sgml":      "text/x-sgml",
    ".sh":        "text/x-scriptsh",
    ".shar":      "application/x-bsh",
    ".shtml":     "text/x-server-parsed-html",
    ".sid":       "audio/x-psid",
    ".skd":       "application/x-koan",
    ".skm":       "application/x-koan",
    ".skp":       "application/x-koan",
    ".skt":       "application/x-koan",
    ".sit":       "application/x-stuffit",
    ".sitx":      "application/x-stuffitx",
    ".sl":        "application/x-seelogo",
    ".smi":       "application/smil",
    ".smil":      "application/smil",
    ".snd":       "audio/basic",
    ".sol":       "application/solids",
    ".spc":       "text/x-speech",
    ".spl":       "application/futuresplash",
    ".spr":       "application/x-sprite",
    ".sprite":    "application/x-sprite",
    ".spx":       "audio/ogg",
    ".src":       "application/x-wais-source",
    ".ssi":       "text/x-server-parsed-html",
    ".ssm":       "application/streamingmedia",
    ".sst":       "application/vndms-pkicertstore",
    ".step":      "application/step",
    ".stl":       "application/sla",
    ".stp":       "application/step",
    ".sv4cpio":   "application/x-sv4cpio",
    ".sv4crc":    "application/x-sv4crc",
    ".svf":       "image/vnddwg",
    ".svg":       "image/svg+xml",
    ".svr":       "application/x-world",
    ".swf":       "application/x-shockwave-flash",
    ".t":         "application/x-troff",
    ".talk":      "text/x-speech",
    ".tar":       "application/x-tar",
    ".tbk":       "application/toolbook",
    ".tcl":       "text/x-scripttcl",
    ".tcsh":      "text/x-scripttcsh",
    ".tex":       "application/x-tex",
    ".texi":      "application/x-texinfo",
    ".texinfo":   "application/x-texinfo",
    ".text":      "text/plain",
    ".tgz":       "application/gnutar",
    ".tif":       "image/tiff",
    ".tiff":      "image/tiff",
    ".tr":        "application/x-troff",
    ".tsi":       "audio/tsp-audio",
    ".tsp":       "application/dsptype",
    ".tsv":       "text/tab-separated-values",
    ".turbot":    "image/florian",
    ".txt":       "text/plain",
    ".uil":       "text/x-uil",
    ".uni":       "text/uri-list",
    ".unis":      "text/uri-list",
    ".unv":       "application/i-deas",
    ".uri":       "text/uri-list",
    ".uris":      "text/uri-list",
    ".ustar":     "application/x-ustar",
    ".uu":        "text/x-uuencode",
    ".uue":       "text/x-uuencode",
    ".vcd":       "application/x-cdlink",
    ".vcf":       "text/x-vcard",
    ".vcard":     "text/x-vcard",
    ".vcs":       "text/x-vcalendar",
    ".vda":       "application/vda",
    ".vdo":       "video/vdo",
    ".vew":       "application/groupwise",
    ".viv":       "video/vivo",
    ".vivo":      "video/vivo",
    ".vmd":       "application/vocaltec-media-desc",
    ".vmf":       "application/vocaltec-media-file",
    ".voc":       "audio/voc",
    ".vos":       "video/vosaic",
    ".vox":       "audio/voxware",
    ".vqe":       "audio/x-twinvq-plugin",
    ".vqf":       "audio/x-twinvq",
    ".vql":       "audio/x-twinvq-plugin",
    ".vrml":      "application/x-vrml",
    ".vrt":       "x-world/x-vrt",
    ".vsd":       "application/x-visio",
    ".vst":       "application/x-visio",
    ".vsw":       "application/x-visio",
    ".w60":       "application/wordperfect60",
    ".w61":       "application/wordperfect61",
    ".w6w":       "application/msword",
    ".wav":       "audio/wav",
    ".wb1":       "application/x-qpro",
    ".wbmp":      "image/vnd.wap.wbmp",
    ".web":       "application/vndxara",
    ".wiz":       "application/msword",
    ".wk1":       "application/x-123",
    ".wmf":       "windows/metafile",
    ".wml":       "text/vnd.wap.wml",
    ".wmlc":      "application/vnd.wap.wmlc",
    ".wmls":      "text/vnd.wap.wmlscript",
    ".wmlsc":     "application/vnd.wap.wmlscriptc",
    ".word":      "application/msword",
    ".wp5":       "application/wordperfect",
    ".wp6":       "application/wordperfect",
    ".wp":        "application/wordperfect",
    ".wpd":       "application/wordperfect",
    ".wq1":       "application/x-lotus",
    ".wri":       "application/mswrite",
    ".wrl":       "application/x-world",
    ".wrz":       "model/vrml",
    ".wsc":       "text/scriplet",
    ".wsrc":      "application/x-wais-source",
    ".wtk":       "application/x-wintalk",
    ".x-png":     "image/png",
    ".xbm":       "image/x-xbitmap",
    ".xdr":       "video/x-amt-demorun",
    ".xgz":       "xgl/drawing",
    ".xif":       "image/vndxiff",
    ".xl":        "application/excel",
    ".xla":       "application/excel",
    ".xlb":       "application/excel",
    ".xlc":       "application/excel",
    ".xld":       "application/excel",
    ".xlk":       "application/excel",
    ".xll":       "application/excel",
    ".xlm":       "application/excel",
    ".xls":       "application/excel",
    ".xlt":       "application/excel",
    ".xlv":       "application/excel",
    ".xlw":       "application/excel",
    ".xm":        "audio/xm",
    ".xml":       "text/xml",
    ".xmz":       "xgl/movie",
    ".xpix":      "application/x-vndls-xpix",
    ".xpm":       "image/x-xpixmap",
    ".xsr":       "video/x-amt-showrun",
    ".xwd":       "image/x-xwd",
    ".xyz":       "chemical/x-pdb",
    ".z":         "application/x-compress",
    ".zip":       "application/zip",
    ".zoo":       "application/octet-stream",
    ".zsh":       "text/x-scriptzsh",
    ".docx":      "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
    ".docm":      "application/vnd.ms-word.document.macroEnabled.12",
    ".dotx":      "application/vnd.openxmlformats-officedocument.wordprocessingml.template",
    ".dotm":      "application/vnd.ms-word.template.macroEnabled.12",
    ".xlsx":      "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
    ".xlsm":      "application/vnd.ms-excel.sheet.macroEnabled.12",
    ".xltx":      "application/vnd.openxmlformats-officedocument.spreadsheetml.template",
    ".xltm":      "application/vnd.ms-excel.template.macroEnabled.12",
    ".xlsb":      "application/vnd.ms-excel.sheet.binary.macroEnabled.12",
    ".xlam":      "application/vnd.ms-excel.addin.macroEnabled.12",
    ".pptx":      "application/vnd.openxmlformats-officedocument.presentationml.presentation",
    ".pptm":      "application/vnd.ms-powerpoint.presentation.macroEnabled.12",
    ".ppsx":      "application/vnd.openxmlformats-officedocument.presentationml.slideshow",
    ".ppsm":      "application/vnd.ms-powerpoint.slideshow.macroEnabled.12",
    ".potx":      "application/vnd.openxmlformats-officedocument.presentationml.template",
    ".potm":      "application/vnd.ms-powerpoint.template.macroEnabled.12",
    ".ppam":      "application/vnd.ms-powerpoint.addin.macroEnabled.12",
    ".sldx":      "application/vnd.openxmlformats-officedocument.presentationml.slide",
    ".sldm":      "application/vnd.ms-powerpoint.slide.macroEnabled.12",
    ".thmx":      "application/vnd.ms-officetheme",
    ".onetoc":    "application/onenote",
    ".onetoc2":   "application/onenote",
    ".onetmp":    "application/onenote",
    ".onepkg":    "application/onenote",
    ".xpi":       "application/x-xpinstall",
}

func init() {
    for ext, typ := range types {
        // skip errors
        mime.AddExtensionType(ext, typ)
    }
}

// typeByExtension returns the MIME type associated with the file extension ext.
// The extension ext should begin with a leading dot, as in ".html".
// When ext has no associated type, typeByExtension returns "".
//
// Extensions are looked up first case-sensitively, then case-insensitively.
//
// The built-in table is small but on unix it is augmented by the local
// system's mime.types file(s) if available under one or more of these
// names:
//
//   /etc/mime.types
//   /etc/apache2/mime.types
//   /etc/apache/mime.types
//
// On Windows, MIME types are extracted from the registry.
//
// Text types have the charset parameter set to "utf-8" by default.
func TypeByExtension(fullfilename string) string {
    ext := filepath.Ext(fullfilename)
    typ := mime.TypeByExtension(ext)

    // mime.TypeByExtension returns as text/plain; | charset=utf-8 the static .js (not always)
    if ext == ".js" && (typ == "text/plain" || typ == "text/plain; charset=utf-8") {

        if ext == ".js" {
            typ = "application/javascript"
        }
    }
    return typ
}

Hope that helped you and other users, don't hesitate to post again if you have more questions!

How to automatically insert a blank row after a group of data

I have a large file in excel dealing with purchase and sale of mutual fund units. Number of rows in a worksheet exceeds 4000. I have no experience with VBA and would like to work with basic excel. Taking the cue from the solutions suggested above, I tried to solve the problem ( to insert blank rows automatically) in the following manner:

  1. I sorted my file according to control fields
  2. I added a column to the file
  3. I used the "IF" function to determine when there is a change in the control data .
  4. If there is a change the result will indicate "yes", otherwise "no"
  5. Then I filtered the data to group all "yes" items
  6. I copied mutual fund names, folio number etc (no financial data)
  7. Then I removed the filter and sorted the file again. The result is a row added at the desired place. (It is not entirely a blank row, because if it is fully blank, sorting will not place the row at the desired place.)
  8. After sorting, you can easily delete all values to get a completely blank row.

This method also may be tried by the readers.

How To Inject AuthenticationManager using Java Configuration in a Custom Filter

Override method authenticationManagerBean in WebSecurityConfigurerAdapter to expose the AuthenticationManager built using configure(AuthenticationManagerBuilder) as a Spring bean:

For example:

   @Bean(name = BeanIds.AUTHENTICATION_MANAGER)
   @Override
   public AuthenticationManager authenticationManagerBean() throws Exception {
       return super.authenticationManagerBean();
   }

What is the correct way to represent null XML elements?

xsi:nil is the correct way to represent a value such that: When the DOM Level 2 call getElementValue() is issued, the NULL value is returned. xsi:nil is also used to indicate a valid element with no content even if that elements content type normally doesn't allow empty elements.

If an empty tag is used, getElementValue() returns the empty string ("") If the tag is omitted, then no author tag is even present. This may be semantically different than setting it to 'nil' (Ex. Setting "Series" to nil may be that the book belongs to no series, while omitting series could mean that series is an inapplicable element to the current element.)

From: The W3C

XML Schema: Structures introduces a mechanism for signaling that an element should be accepted as ·valid· when it has no content despite a content type which does not require or even necessarily allow empty content. An element may be ·valid· without content if it has the attribute xsi:nil with the value true. An element so labeled must be empty, but can carry attributes if permitted by the corresponding complex type.

A clarification:
If you have a book xml element and one of the child elements is book:series you have several options when filling it out:

  1. Removing the element entirely - This can be done when you wish to indicate that series does not apply to this book or that book is not part of a series. In this case xsl transforms (or other event based processors) that have a template that matches book:series will never be called. For example, if your xsl turns the book element into table row (xhtml:tr) you may get the incorrect number of table cells (xhtml:td) using this method.
  2. Leaving the element empty - This could indicate that the series is "", or is unknown, or that the book is not part of a series. Any xsl transform (or other evernt based parser) that matches book:series will be called. The value of current() will be "". You will get the same number of xhtml:td tags using this method as with the next described one.
  3. Using xsi:nil="true" - This signifies that the book:series element is NULL, not just empty. Your xsl transform (or other event based parser) that have a template matching book:series will be called. The value of current() will be empty (not empty string). The main difference between this method and (2) is that the schema type of book:series does not need to allow the empty string ("") as a valid value. This makes no real sense for a series element, but for a language element that is defined as an enumerated type in the schema, xsi:nil="true" allows the element to have no data. Another example would be elements of type decimal. If you want them to be empty you can union an enumerated string that only allows "" and a decimal, or use a decimal that is nillable.

Singleton in Android

You are copying singleton's customVar into a singletonVar variable and changing that variable does not affect the original value in singleton.

// This does not update singleton variable
// It just assigns value of your local variable
Log.d("Test",singletonVar);
singletonVar="World";
Log.d("Test",singletonVar);

// This actually assigns value of variable in singleton
Singleton.customVar = singletonVar;

How can INSERT INTO a table 300 times within a loop in SQL?

DECLARE @first AS INT = 1
DECLARE @last AS INT = 300

WHILE(@first <= @last)
BEGIN
    INSERT INTO tblFoo VALUES(@first)
    SET @first += 1
END

How to check if input date is equal to today's date?

for completeness, taken from this solution:

You could use toDateString:

var today = new Date();
var isToday = (today.toDateString() == otherDate.toDateString());

no library dependencies, and looking cleaner than the 'setHours()' approach shown in a previous answer, imho

Save each sheet in a workbook to separate CSV files

@AlexDuggleby: you don't need to copy the worksheets, you can save them directly. e.g.:

Public Sub SaveWorksheetsAsCsv()
Dim WS As Excel.Worksheet
Dim SaveToDirectory As String

    SaveToDirectory = "C:\"

    For Each WS In ThisWorkbook.Worksheets
        WS.SaveAs SaveToDirectory & WS.Name, xlCSV
    Next

End Sub

Only potential problem is that that leaves your workbook saved as the last csv file. If you need to keep the original workbook you will need to SaveAs it.

Importing packages in Java

You should use

import Dan.Vik;

This makes the class visible and the its public methods available.

jQuery .load() call doesn't execute JavaScript in loaded HTML file

$("#images").load(location.href+" #images",function(){
    $.getScript("js/productHelper.js"); 
});

Bigger Glyphicons

You can just give the glyphicon a font-size to your liking:

span.glyphicon-link {
    font-size: 1.2em;
}

Get list of filenames in folder with Javascript

I use the following (stripped-down code) in Firefox 69.0 (on Ubuntu) to read a directory and show the image as part of a digital photo frame. The page is made in HTML, CSS, and JavaScript, and it is located on the same machine where I run the browser. The images are located on the same machine as well, so there is no viewing from "outside".

var directory = <path>;
var xmlHttp = new XMLHttpRequest();
xmlHttp.open('GET', directory, false); // false for synchronous request
xmlHttp.send(null);
var ret = xmlHttp.responseText;
var fileList = ret.split('\n');
for (i = 0; i < fileList.length; i++) {
    var fileinfo = fileList[i].split(' ');
    if (fileinfo[0] == '201:') {
        document.write(fileinfo[1] + "<br>");
        document.write('<img src=\"' + directory + fileinfo[1] + '\"/>');
    }
}

This requires the policy security.fileuri.strict_origin_policy to be disabled. This means it might not be a solution you want to use. In my case I deemed it ok.

cd into directory without having permission

Unless you have sudo permissions to change it or its in your own usergroup/account you will not be able to get into it.

Check out man chmod in the terminal for more information about changing permissions of a directory.

How to compare two object variables in EL expression language?

In Expression Language you can just use the == or eq operator to compare object values. Behind the scenes they will actually use the Object#equals(). This way is done so, because until with the current EL 2.1 version you cannot invoke methods with other signatures than standard getter (and setter) methods (in the upcoming EL 2.2 it would be possible).

So the particular line

<c:when test="${lang}.equals(${pageLang})">

should be written as (note that the whole expression is inside the { and })

<c:when test="${lang == pageLang}">

or, equivalently

<c:when test="${lang eq pageLang}">

Both are behind the scenes roughly interpreted as

jspContext.findAttribute("lang").equals(jspContext.findAttribute("pageLang"))

If you want to compare constant String values, then you need to quote it

<c:when test="${lang == 'en'}">

or, equivalently

<c:when test="${lang eq 'en'}">

which is behind the scenes roughly interpreted as

jspContext.findAttribute("lang").equals("en")

How to check if a scope variable is undefined in AngularJS template?

<p ng-show="angular.isUndefined(foo)">Show this if $scope.foo === undefined</p>

Removing the remembered login and password list in SQL Server Management Studio

In my scenario I only wanted to remove a specific username/password from the list which had many other saved connections I didn't want to forget. It turns out the SqlStudio.bin file others are discussing here is a .NET binary serialization of the Microsoft.SqlServer.Management.UserSettings.SqlStudio class, which can be deserialized, modified and reserialized to modify specific settings.

To accomplish removal of the specific login, I created a new C# .Net 4.6.1 console application and added a reference to the namespace which is located in the following dll: C:\Program Files (x86)\Microsoft SQL Server\130\Tools\Binn\ManagementStudio\Microsoft.SqlServer.Management.UserSettings.dll (your path may differ slightly depending on SSMS version)

From there I could easily create and modify the settings as desired:

using System.IO;
using System.Runtime.Serialization.Formatters.Binary;
using Microsoft.SqlServer.Management.UserSettings;

class Program
{
    static void Main(string[] args)
    {
        var settingsFile = new FileInfo(@"C:\Users\%username%\AppData\Roaming\Microsoft\SQL Server Management Studio\13.0\SqlStudio.bin");

        // Backup our original file just in case...
        File.Copy(settingsFile.FullName, settingsFile.FullName + ".backup");

        BinaryFormatter fmt = new BinaryFormatter();

        SqlStudio settings = null;

        using(var fs = settingsFile.Open(FileMode.Open))
        {
            settings = (SqlStudio)fmt.Deserialize(fs);
        }

        // The structure of server types / servers / connections requires us to loop
        // through multiple nested collections to find the connection to be removed.
        // We start here with the server types

        var serverTypes = settings.SSMS.ConnectionOptions.ServerTypes;

        foreach (var serverType in serverTypes)
        {
            foreach (var server in serverType.Value.Servers)
            {
                // Will store the connection for the provided server which should be removed
                ServerConnectionSettings removeConn = null;

                foreach (var conn in server.Connections)
                {
                    if (conn.UserName == "adminUserThatShouldBeRemoved")
                    {
                        removeConn = conn;
                        break;
                    }
                }

                if (removeConn != null)
                {
                    server.Connections.RemoveItem(removeConn);
                }
            }
        }

        using (var fs = settingsFile.Open(FileMode.Create))
        {
            fmt.Serialize(fs, settings);
        }
    }
}

ORA-01950: no privileges on tablespace 'USERS'

You cannot insert data because you have a quota of 0 on the tablespace. To fix this, run

ALTER USER <user> quota unlimited on <tablespace name>;

or

ALTER USER <user> quota 100M on <tablespace name>;

as a DBA user (depending on how much space you need / want to grant).

How can I read large text files in Python, line by line, without loading it into memory?

You are better off using an iterator instead. Relevant: http://docs.python.org/library/fileinput.html

From the docs:

import fileinput
for line in fileinput.input("filename"):
    process(line)

This will avoid copying the whole file into memory at once.

html5: display video inside canvas

You need to update currentTime video element and then draw the frame in canvas. Don't init play() event on the video.

You can also use for ex. this plugin https://github.com/tstabla/stVideo

How to add a RequiredFieldValidator to DropDownList control?

For the most part you treat it as if you are validating any other kind of control but use the InitialValue property of the required field validator.

<asp:RequiredFieldValidator ID="rfv1" runat="server" ControlToValidate="your-dropdownlist" InitialValue="Please select" ErrorMessage="Please select something" />

Basically what it's saying is that validation will succeed if any other value than the 1 set in InitialValue is selected in the dropdownlist.

If databinding you will need to insert the "Please select" value afterwards as follows

this.ddl1.Items.Insert(0, "Please select");

Bootstrap control with multiple "data-toggle"

Just for complement @Roman Holzner answer...

In my case, I have a button that shows the tooltip and it should remain disabled until furthermore actions. Using his approach, the modal works even if the button is disabled, because its call is outside the button - I'm in a Laravel blade file, just to be clear :)

<span data-toggle="modal" data-target="#confirm-delete" data-href="{{ $e->id }}">
    <button name="delete" class="btn btn-default" data-toggle="tooltip" data-placement="bottom" title="Excluir Entrada" disabled>
        <i class="fa fa-trash fa-fw"></i>
    </button>
</span>

So if you want to show the modal only when the button is active, you should change the order of the tags:

<span data-toggle="tooltip" data-placement="bottom" title="Excluir Entrada" disabled>
    <button name="delete" class="btn btn-default" data-href="{{ $e->id }}" data-toggle="modal" data-target="#confirm-delete" disabled>
        <i class="fa fa-trash fa-fw"></i>
    </button>
</span>

If you want to test it out, change the attribute with a JQuery code:

$('button[name=delete]').attr('disabled', false);

How to show Page Loading div until the page has finished loading?

This script will add a div that covers the entire window as the page loads. It will show a CSS-only loading spinner automatically. It will wait until the window (not the document) finishes loading, then it will wait an optional extra few seconds.

  • Works with jQuery 3 (it has a new window load event)
  • No image needed but it's easy to add one
  • Change the delay for more branding or instructions
  • Only dependency is jQuery.

CSS loader code from https://projects.lukehaas.me/css-loaders

_x000D_
_x000D_
    _x000D_
$('body').append('<div style="" id="loadingDiv"><div class="loader">Loading...</div></div>');_x000D_
$(window).on('load', function(){_x000D_
  setTimeout(removeLoader, 2000); //wait for page load PLUS two seconds._x000D_
});_x000D_
function removeLoader(){_x000D_
    $( "#loadingDiv" ).fadeOut(500, function() {_x000D_
      // fadeOut complete. Remove the loading div_x000D_
      $( "#loadingDiv" ).remove(); //makes page more lightweight _x000D_
  });  _x000D_
}
_x000D_
        .loader,_x000D_
        .loader:after {_x000D_
            border-radius: 50%;_x000D_
            width: 10em;_x000D_
            height: 10em;_x000D_
        }_x000D_
        .loader {            _x000D_
            margin: 60px auto;_x000D_
            font-size: 10px;_x000D_
            position: relative;_x000D_
            text-indent: -9999em;_x000D_
            border-top: 1.1em solid rgba(255, 255, 255, 0.2);_x000D_
            border-right: 1.1em solid rgba(255, 255, 255, 0.2);_x000D_
            border-bottom: 1.1em solid rgba(255, 255, 255, 0.2);_x000D_
            border-left: 1.1em solid #ffffff;_x000D_
            -webkit-transform: translateZ(0);_x000D_
            -ms-transform: translateZ(0);_x000D_
            transform: translateZ(0);_x000D_
            -webkit-animation: load8 1.1s infinite linear;_x000D_
            animation: load8 1.1s infinite linear;_x000D_
        }_x000D_
        @-webkit-keyframes load8 {_x000D_
            0% {_x000D_
                -webkit-transform: rotate(0deg);_x000D_
                transform: rotate(0deg);_x000D_
            }_x000D_
            100% {_x000D_
                -webkit-transform: rotate(360deg);_x000D_
                transform: rotate(360deg);_x000D_
            }_x000D_
        }_x000D_
        @keyframes load8 {_x000D_
            0% {_x000D_
                -webkit-transform: rotate(0deg);_x000D_
                transform: rotate(0deg);_x000D_
            }_x000D_
            100% {_x000D_
                -webkit-transform: rotate(360deg);_x000D_
                transform: rotate(360deg);_x000D_
            }_x000D_
        }_x000D_
        #loadingDiv {_x000D_
            position:absolute;;_x000D_
            top:0;_x000D_
            left:0;_x000D_
            width:100%;_x000D_
            height:100%;_x000D_
            background-color:#000;_x000D_
        }
_x000D_
This script will add a div that covers the entire window as the page loads. It will show a CSS-only loading spinner automatically. It will wait until the window (not the document) finishes loading._x000D_
_x000D_
  <ul>_x000D_
    <li>Works with jQuery 3, which has a new window load event</li>_x000D_
    <li>No image needed but it's easy to add one</li>_x000D_
    <li>Change the delay for branding or instructions</li>_x000D_
    <li>Only dependency is jQuery.</li>_x000D_
  </ul>_x000D_
_x000D_
Place the script below at the bottom of the body._x000D_
_x000D_
CSS loader code from https://projects.lukehaas.me/css-loaders_x000D_
_x000D_
<!-- Place the script below at the bottom of the body -->_x000D_
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
_x000D_
_x000D_
_x000D_

OSError: [Errno 2] No such file or directory while using python subprocess in Django

Use shell=True if you're passing a string to subprocess.call.

From docs:

If passing a single string, either shell must be True or else the string must simply name the program to be executed without specifying any arguments.

subprocess.call(crop, shell=True)

or:

import shlex
subprocess.call(shlex.split(crop))

WAMP Server ERROR "Forbidden You don't have permission to access /phpmyadmin/ on this server."

Change httpd.conf file as follows:

from

<Directory />
    AllowOverride none
    Require all denied
</Directory>

to

<Directory />
    AllowOverride none
    Require all granted
</Directory>

How to merge rows in a column into one cell in excel?

If you prefer to do this without VBA, you can try the following:

  1. Have your data in cells A1:A999 (or such)
  2. Set cell B1 to "=A1"
  3. Set cell B2 to "=B1&A2"
  4. Copy cell B2 all the way down to B999 (e.g. by copying B2, selecting cells B3:B99 and pasting)

Cell B999 will now contain the concatenated text string you are looking for.

How do I export (and then import) a Subversion repository?

The tool to do that would be

svnadmin dump

But for this to work, you need filesystem-access to the repository. And once you have that (and provided the repository is in FSFS format), you can just copy the repository to its new location (if it's in BDB format, dump/load is strongly recommended).

If you do not have filesystem access, you would have to ask your repository provider to provide the dump for you (and make them delete their repository - and hope they comply)

Webfont Smoothing and Antialiasing in Firefox and Opera

When the color of text is dark, in Safari and Chrome, I have better result with the text-stroke css property.

-webkit-text-stroke: 0.5px #000;

How to declare strings in C

char *p = "String";   means pointer to a string type variable.

char p3[5] = "String"; means you are pre-defining the size of the array to consist of no more than 5 elements. Note that,for strings the null "\0" is also considered as an element.So,this statement would give an error since the number of elements is 7 so it should be:

char p3[7]= "String";

CMD: Export all the screen content to a text file

If you want to append a file instead of constantly making a new one/deleting the old one's content, use double > marks. A single > mark will overwrite all the file's content.

Overwrite file

MyCommand.exe>file.txt

^This will open file.txt if it already exists and overwrite the data, or create a new file and fill it with your output

Append file from its end-point

MyCommand.exe>>file.txt

^This will append file.txt from its current end of file if it already exists, or create a new file and fill it with your output.


Update #1 (advanced):

My batch-fu has improved over time, so here's some minor updates.

If you want to differentiate between error output and normal output for a program that correctly uses Standard streams, STDOUT/STDERR, you can do this with minor changes to the syntax. I'll just use > for overwriting for these examples, but they work perfectly fine with >> for append, in regards to file-piping output re-direction.

The 1 before the >> or > is the flag for STDOUT. If you need to actually output the number one or two before the re-direction symbols, this can lead to strange, unintuitive errors if you don't know about this mechanism. That's especially relevant when outputting a single result number into a file. 2 before the re-direction symbols is for STDERR.

Now that you know that you have more than one stream available, this is a good time to show the benefits of outputting to nul. Now, outputting to nul works the same way conceptually as outputting to a file. You don't see the content in your console. Instead of it going to file or your console output, it goes into the void.

STDERR to file and suppress STDOUT

MyCommand.exe 1>nul 2>errors.txt

STDERR to file to only log errors. Will keep STDOUT in console

MyCommand.exe 2>errors.txt

STDOUT to file and suppress STDERR

MyCommand.exe 1>file.txt 2>nul

STDOUT only to file. Will keep STDERR in console

MyCommand.exe 1>file.txt

STDOUT to one file and STDERR to another file

MyCommand.exe 1>stdout.txt 2>errors.txt

The only caveat I have here is that it can create a 0-byte file for an unused stream if one of the streams never gets used. Basically, if no errors occurred, you might end up with a 0-byte errors.txt file.

Update #2

I started noticing weird behavior when writing console apps that wrote directly to STDERR, and realized that if I wanted my error output to go to the same file when using basic piping, I either had to combine streams 1 and 2 or just use STDOUT. The problem with that problem is I didn't know about the correct way to combine streams, which is this:

%command% > outputfile 2>&1

Therefore, if you want all STDOUT and STDERR piped into the same stream, make sure to use that like so:

MyCommand.exe > file.txt 2>&1

The redirector actually defaults to 1> or 1>>, even if you don't explicitly use 1 in front of it if you don't use a number in front of it, and the 2>&1 combines the streams.

Update #3 (simple)

Null for Everything

If you want to completely suppress STDOUT and STDERR you can do it this way. As a warning not all text pipes use STDOUT and STDERR but it will work for a vast majority of use cases.

STD* to null MyCommand.exe>nul 2>&1

Copying a CMD or Powershell session's command output

If all you want is the command output from a CMD or Powershell session that you just finished up, or any other shell for that matter you can usually just select that console from that session, CTRL + A to select all content, then CTRL + C to copy the content. Then you can do whatever you like with the copied content while it's in your clipboard.

How to represent empty char in Java Character class

Use the \b operator (the backspace escape operator) in the second parameter

String test= "Anna Banana";

System.out.println(test); //returns Anna Banana<br><br>
System.out.println(test.replaceAll(" ","\b")); //returns AnnaBanana removing all the spaces in the string

Calling the base class constructor from the derived class constructor

The constructor of PetStore will call a constructor of Farm; there's no way you can prevent it. If you do nothing (as you've done), it will call the default constructor (Farm()); if you need to pass arguments, you'll have to specify the base class in the initializer list:

PetStore::PetStore()
    : Farm( neededArgument )
    , idF( 0 )
{
}

(Similarly, the constructor of PetStore will call the constructor of nameF. The constructor of a class always calls the constructors of all of its base classes and all of its members.)

Automatically deleting related rows in Laravel (Eloquent ORM)

yeah, but as @supersan stated upper in a comment, if you delete() on a QueryBuilder, the model event will not be fired, because we are not loading the model itself, then calling delete() on that model.

The events are fired only if we use the delete function on a Model Instance.

So, this beeing said:

if user->hasMany(post)
and if post->hasMany(tags)

in order to delete the post tags when deleting the user, we would have to iterate over $user->posts and calling $post->delete()

foreach($user->posts as $post) { $post->delete(); } -> this will fire the deleting event on Post

VS

$user->posts()->delete() -> this will not fire the deleting event on post because we do not actually load the Post Model (we only run a SQL like: DELETE * from posts where user_id = $user->id and thus, the Post model is not even loaded)

Replace invalid values with None in Pandas DataFrame

With Pandas version =1.0.0, I would use DataFrame.replace or Series.replace:

df.replace(old_val, pd.NA, inplace=True)

This is better for two reasons:

  1. It uses pd.NA instead of None or np.nan.
  2. It replaces the value in-place which could be more memory efficient.

Determine the size of an InputStream

You can't determine the amount of data in a stream without reading it; you can, however, ask for the size of a file:

http://java.sun.com/javase/6/docs/api/java/io/File.html#length()

If that isn't possible, you can write the bytes you read from the input stream to a ByteArrayOutputStream which will grow as required.

CSS table td width - fixed, not flexible

Chrome 37. for non fixed table:

td {
    width: 30px;
    max-width: 30px;
    overflow: hidden;
}

first two important! else - its flow away!

Insert variable values in the middle of a string

String.Format("Hi We have these flights for you: {0}. Which one do you want",
                              flights);

EDIT: you can even save the "template" string separately (for instance you could store it in a configuration file and retrieve it from there), like this:

string flights = "Flight A, B,C,D";

string template = @"Hi We have these flights for you: {0}. Which one do you want";
Console.WriteLine(String.Format(template, flights));

EDIT2: whoops, sorry I see that @DanPuzey had already suggested something very similar to my EDIT (but somewhat better)

Does HTML5 <video> playback support the .avi format?

There are three formats with a reasonable level of support: H.264 (MPEG-4 AVC), OGG Theora (VP3) and WebM (VP8). See the wiki linked by Sam for which browsers support which; you will typically need at least one of those plus Flash fallback.

Whilst most browsers won't touch AVI, there are some browser builds that expose all the multimedia capabilities of the underlying OS to <video>. These browser will indeed be able to play AVI, as long as they have matching codecs installed (AVI can contain about a million different video and audio formats). In particular Safari on OS X with QuickTime, or Konqi with GStreamer.

Personally I think this is an absolutely disastrous idea, as it exposes a very large codec codebase to the net, a codebase that was mostly not written to be resistant to network attacks. One of the worst drawbacks of media player plugins was the huge number of security holes they made available to every web page exploit. Let's not make this mistake again.

Merging two images with PHP

The GD Image Manipulation Library in PHP is probably the best for working with images in PHP. Try one of the imagecopy functions (imagecopy, imagecopymerge, ...). Each of them combine 2 images in different ways. See the php documentation on imagecopy for more information.

JSON find in JavaScript

I had come across this issue for a complex model with several nested objects. A good example of what I was looking at doing would be this: Lets say you have a polaroid of yourself. And that picture is then put into a trunk of a car. The car is inside of a large crate. The crate is in the hold of a large ship with many other crates. I had to search the hold, look in the crates, check the trunk, and then look for an existing picture of me.

I could not find any good solutions online to use, and using .filter() only works on arrays. Most solutions suggested just checking to see if model["yourpicture"] existed. This was very undesirable because, from the example, that would only search the hold of the ship and I needed a way to get them from farther down the rabbit hole.

This is the recursive solution I made. In comments, I confirmed from T.J. Crowder that a recursive version would be required. I thought I would share it in case anyone came across a similar complex situation.

function ContainsKeyValue( obj, key, value ){
    if( obj[key] === value ) return true;
    for( all in obj )
    {
        if( obj[all] != null && obj[all][key] === value ){
            return true;
        }
        if( typeof obj[all] == "object" && obj[all]!= null ){
            var found = ContainsKeyValue( obj[all], key, value );
            if( found == true ) return true;
        }
    }
    return false;
}

This will start from a given object inside of the graph, and recurse down any objects found. I use it like this:

var liveData = [];
for( var items in viewmodel.Crates )
{
    if( ContainsKeyValue( viewmodel.Crates[items], "PictureId", 6 ) === true )
    {
        liveData.push( viewmodel.Crates[items] );
    }
}

Which will produce an array of the Crates which contained my picture.

How to open a local disk file with JavaScript?

Javascript cannot typically access local files in new browsers but the XMLHttpRequest object can be used to read files. So it is actually Ajax (and not Javascript) which is reading the file.

If you want to read the file abc.txt, you can write the code as:

var txt = '';
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function(){
  if(xmlhttp.status == 200 && xmlhttp.readyState == 4){
    txt = xmlhttp.responseText;
  }
};
xmlhttp.open("GET","abc.txt",true);
xmlhttp.send();

Now txt contains the contents of the file abc.txt.

What is the difference between an annotated and unannotated tag?

Push annotated tags, keep lightweight local

man git-tag says:

Annotated tags are meant for release while lightweight tags are meant for private or temporary object labels.

And certain behaviors do differentiate between them in ways that this recommendation is useful e.g.:

  • annotated tags can contain a message, creator, and date different than the commit they point to. So you could use them to describe a release without making a release commit.

    Lightweight tags don't have that extra information, and don't need it, since you are only going to use it yourself to develop.

  • git push --follow-tags will only push annotated tags
  • git describe without command line options only sees annotated tags

Internals differences

  • both lightweight and annotated tags are a file under .git/refs/tags that contains a SHA-1

  • for lightweight tags, the SHA-1 points directly to a commit:

    git tag light
    cat .git/refs/tags/light
    

    prints the same as the HEAD's SHA-1.

    So no wonder they cannot contain any other metadata.

  • annotated tags point to a tag object in the object database.

    git tag -as -m msg annot
    cat .git/refs/tags/annot
    

    contains the SHA of the annotated tag object:

    c1d7720e99f9dd1d1c8aee625fd6ce09b3a81fef
    

    and then we can get its content with:

    git cat-file -p c1d7720e99f9dd1d1c8aee625fd6ce09b3a81fef
    

    sample output:

    object 4284c41353e51a07e4ed4192ad2e9eaada9c059f
    type commit
    tag annot
    tagger Ciro Santilli <[email protected]> 1411478848 +0200
    
    msg
    -----BEGIN PGP SIGNATURE-----
    Version: GnuPG v1.4.11 (GNU/Linux)
    
    <YOUR PGP SIGNATURE>
    -----END PGP SIGNAT
    

    And this is how it contains extra metadata. As we can see from the output, the metadata fields are:

    A more detailed analysis of the format is present at: What is the format of a git tag object and how to calculate its SHA?

Bonuses

  • Determine if a tag is annotated:

    git cat-file -t tag
    

    Outputs

    • commit for lightweight, since there is no tag object, it points directly to the commit
    • tag for annotated, since there is a tag object in that case
  • List only lightweight tags: How can I list all lightweight tags?

dplyr change many data types

It's a one-liner with mutate_at:

dat %>% mutate_at("l1", factor) %>% mutate_at("l2", as.numeric)

Python argparse: default value or specified value

The difference between:

parser.add_argument("--debug", help="Debug", nargs='?', type=int, const=1, default=7)

and

parser.add_argument("--debug", help="Debug", nargs='?', type=int, const=1)

is thus:

myscript.py => debug is 7 (from default) in the first case and "None" in the second

myscript.py --debug => debug is 1 in each case

myscript.py --debug 2 => debug is 2 in each case

What's the difference between django OneToOneField and ForeignKey?

A ForeignKey is for one-to-many, so a Car object might have many Wheels, each Wheel having a ForeignKey to the Car it belongs to. A OneToOneField would be like an Engine, where a Car object can have one and only one.

Checking character length in ruby

Instead of using a regular expression, just check if string.length > 25

How can I find all the subsets of a set, with exactly n elements?

itertools.combinations is your friend if you have Python 2.6 or greater. Otherwise, check the link for an implementation of an equivalent function.

import itertools
def findsubsets(S,m):
    return set(itertools.combinations(S, m))

S: The set for which you want to find subsets
m: The number of elements in the subset

Force flushing of output to a file while bash script is still running

Would this help?

tail -f access.log | stdbuf -oL cut -d ' ' -f1 | uniq 

This will immediately display unique entries from access.log using the stdbuf utility.

Center an element in Bootstrap 4 Navbar

Updated for Bootstrap 4.1+

Bootstrap 4 the navbar now uses flexbox so the Website Name can be centered using mx-auto. The left and right side menus don't require floats.

<nav class="navbar navbar-expand-md navbar-fixed-top navbar-dark bg-dark main-nav">
    <div class="container">
        <ul class="nav navbar-nav">
            <li class="nav-item active">
                <a class="nav-link" href="#">Home</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Download</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Register</a>
            </li>
        </ul>
        <ul class="nav navbar-nav mx-auto">
            <li class="nav-item"><a class="nav-link" href="#">Website Name</a></li>
        </ul>
        <ul class="nav navbar-nav">
            <li class="nav-item">
                <a class="nav-link" href="#">Rates</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Help</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Contact</a>
            </li>
        </ul>
    </div>
</nav>

Navbar center with mx-auto Demo

If the Navbar only has a single navbar-nav, then justify-content-center can also be used to center.

EDIT

In the solution above, the Website Name is centered relative to the left and right navbar-nav so if the width of these adjacent navs are different the Website Name is no longer centered.

enter image description here

To resolve this, one of the flexbox workarounds for absolute centering can be used...

Option 1 - Use position:absolute;

Since it's ok to use absolute positioning in flexbox, one option is to use this on the item to be centered.

.abs-center-x {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
}

Navbar center with absolute position Demo

Option 2 - Use flexbox nesting

Finally, another option is to make the centered item also display:flexbox (using d-flex) and center justified. In this case each navbar component must have flex-grow:1

As of Bootstrap 4 Beta, the Navbar is now display:flex. Bootstrap 4.1.0 includes a new flex-fill class to make each nav section fill the width:

<nav class="navbar navbar-expand-sm navbar-dark bg-dark main-nav">
    <div class="container justify-content-center">
        <ul class="nav navbar-nav flex-fill w-100 flex-nowrap">
            <li class="nav-item active">
                <a class="nav-link" href="#">Home</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Download</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Register</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">More</a>
            </li>
        </ul>
        <ul class="nav navbar-nav flex-fill justify-content-center">
            <li class="nav-item"><a class="nav-link" href="#">Center</a></li>
        </ul>
        <ul class="nav navbar-nav flex-fill w-100 justify-content-end">
            <li class="nav-item">
                <a class="nav-link" href="#">Help</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Contact</a>
            </li>
        </ul>
    </div>
</nav>

Navbar center with flexbox nesting Demo

Prior to Bootstrap 4.1.0 you can add the flex-fill class like this...

.flex-fill {
   flex:1
}

As of 4.1 flex-fill is included in Bootstrap.


Bootstrap 4 Navbar center demos
More centering demos
Center links on desktop, left align on mobile

Related:
How to center nav-items in Bootstrap?
Bootstrap NavBar with left, center or right aligned items
How move 'nav' element under 'navbar-brand' in my Navbar

enter image description here

Java - get the current class name?

In your example, this probably refers to an anonymous class instance. Java gives a name to those classes by appending a $number to the name of the enclosing class.

How to delete/truncate tables from Hadoop-Hive?

You need to drop the table and then recreate it and then load it again

Best way to store password in database

I may be slightly off-topic as you did mention the need for a username and password, and my understanding of the issue is admitedly not the best but is OpenID something worth considering?

If you use OpenID then you don't end up storing any credentials at all if I understand the technology correctly and users can use credentials that they already have, avoiding the need to create a new identity that is specific to your application.

It may not be suitable if the application in question is purely for internal use though

RPX provides a nice easy way to intergrate OpenID support into an application.

Error Message : Cannot find or open the PDB file

I'm also a newbie to CUDA/Visual studio and encountered the same problem with a couple of the samples. If you run DEBUG-> Start Debugging, then repeatedly step over (F10) you'll see the output window appear and get populated. Normal execution returns nomal completion status 0x0 (as you observed) and the output window is closed.

What's the best way to send a signal to all members of a process group?

pkill -TERM -P 27888

This will kill all processes that have the parent process ID 27888.

Or more robust:

CPIDS=$(pgrep -P 27888); (sleep 33 && kill -KILL $CPIDS &); kill -TERM $CPIDS

which schedule killing 33 second later and politely ask processes to terminate.

See this answer for terminating all descendants.

HTTP Status 504

If your using ASP.Net 5 (now known as ASP.Net Core v1) ensure in your project.json "commands" section for each site you are hosting that the Kestrel proxy listening port differs between sites, otherwise one site will work but the other will return a 504 gateway timeout.

 "commands": {
    "web": "Microsoft.AspNet.Server.Kestrel --server.urls http://localhost:5090"
  },

How to add extension methods to Enums

You can also add an extension method to the Enum type rather than an instance of the Enum:

/// <summary> Enum Extension Methods </summary>
/// <typeparam name="T"> type of Enum </typeparam>
public class Enum<T> where T : struct, IConvertible
{
    public static int Count
    {
        get
        {
            if (!typeof(T).IsEnum)
                throw new ArgumentException("T must be an enumerated type");

            return Enum.GetNames(typeof(T)).Length;
        }
    }
}

You can invoke the extension method above by doing:

var result = Enum<Duration>.Count;

It's not a true extension method. It only works because Enum<> is a different type than System.Enum.

#define in Java

Manifold Preprocessor implemented as a javac compiler plugin is designed exclusively for conditional compilation of Java source code. It uses familiar C/C++ style of directives: #define, #undef, #if, #elif, #else, #endif, #error. and #warning.

It has Maven and Gradle plugins.

How to fix date format in ASP .NET BoundField (DataFormatString)?

Formatting depends on the server's culture setting. If you use en-US culture, you can use Short Date Pattern like {0:d}

For example, it formats 6/15/2009 1:45:30 to 6/15/2009

You can check more formats from BoundField.DataFormatString

What is the PHP syntax to check "is not null" or an empty string?

Use empty(). It checks for both empty strings and null.

if (!empty($_POST['user'])) {
  // do stuff
}

From the manual:

The following things are considered to be empty:

"" (an empty string)  
0 (0 as an integer)  
0.0 (0 as a float)  
"0" (0 as a string)    
NULL  
FALSE  
array() (an empty array)  
var $var; (a variable declared, but without a value in a class)  

Using reflection in Java to create a new instance with the reference variable type set to the new instance class name?

//====Single Class Reference used to retrieve object for fields and initial values. Performance enhancing only====          
Class<?>    reference           =   vector.get(0).getClass();
Object      obj                 =   reference.newInstance();
Field[]     objFields           =   obj.getClass().getFields(); 

Pull request vs Merge request

There is a subtle difference in terms of conflict management. In case of conflicts, a pull request in Github will result in a merge commit on the destination branch. In Gitlab, when a conflict is found, the modifications made will be on a merge commit on the source branch.

See https://docs.gitlab.com/ee/user/project/merge_requests/resolve_conflicts.html

"GitLab resolves conflicts by creating a merge commit in the source branch that is not automatically merged into the target branch. This allows the merge commit to be reviewed and tested before the changes are merged, preventing unintended changes entering the target branch without review or breaking the build."

How to execute cmd commands via Java

This because every runtime.exec(..) returns a Process class that should be used after the execution instead that invoking other commands by the Runtime class

If you look at Process doc you will see that you can use

  • getInputStream()
  • getOutputStream()

on which you should work by sending the successive commands and retrieving the output..

How to redirect stderr and stdout to different files in the same line in script?

Or if you like to mix outputs (stdout & stderr) in one single file you may want to use:

command > merged-output.txt 2>&1

Double Iteration in List Comprehension

If you want to keep the multi dimensional array, one should nest the array brackets. see example below where one is added to every element.

>>> a = [[1, 2], [3, 4]]

>>> [[col +1 for col in row] for row in a]
[[2, 3], [4, 5]]

>>> [col +1 for row in a for col in row]
[2, 3, 4, 5]

bash: Bad Substitution

in my case (under ubuntu 18.04), I have mixed $( ${} ) that works fine:

BACKUPED_NB=$(ls ${HOST_BACKUP_DIR}*${CONTAINER_NAME}.backup.sql.gz | wc --lines)

full example here.

NULL or BLANK fields (ORACLE)

Try the nvl function. select count(nvl(col_name,0)) from table.

Sorry I reread the OP. What is the table structure? is the column varchar or char as that will make a difference?

try

select count(col_name), distinct(col_name) from table group by distinct(col_name)  

/can't remember if you need distinct in the group by but I think not/

and see if it gives you a return with a column name that is blank.

HTTP Error 401.2 - Unauthorized You are not authorized to view this page due to invalid authentication headers

I had the same issue, and spent quite a bit of time trying to track down the solution. I had Anonymous Authentication set up at two different levels with two different users. Make sure that you're not overwriting your set up at a lower level.

How to correctly dismiss a DialogFragment?

CustomFragment dialog = (CustomDataFragment) getSupportFragmentManager().findFragmentByTag("Fragment_TAG");
if (dialog != null) {
  dialog.dismiss();
}

Convert Rows to columns using 'Pivot' in SQL Server

I'm writing an sp that could be useful for this purpose, basically this sp pivot any table and return a new table pivoted or return just the set of data, this is the way to execute it:

Exec dbo.rs_pivot_table @schema=dbo,@table=table_name,@column=column_to_pivot,@agg='sum([column_to_agg]),avg([another_column_to_agg]),',
        @sel_cols='column_to_select1,column_to_select2,column_to_select1',@new_table=returned_table_pivoted;

please note that in the parameter @agg the column names must be with '[' and the parameter must end with a comma ','

SP

Create Procedure [dbo].[rs_pivot_table]
    @schema sysname=dbo,
    @table sysname,
    @column sysname,
    @agg nvarchar(max),
    @sel_cols varchar(max),
    @new_table sysname,
    @add_to_col_name sysname=null
As
--Exec dbo.rs_pivot_table dbo,##TEMPORAL1,tip_liq,'sum([val_liq]),sum([can_liq]),','cod_emp,cod_con,tip_liq',##TEMPORAL1PVT,'hola';
Begin

    Declare @query varchar(max)='';
    Declare @aggDet varchar(100);
    Declare @opp_agg varchar(5);
    Declare @col_agg varchar(100);
    Declare @pivot_col sysname;
    Declare @query_col_pvt varchar(max)='';
    Declare @full_query_pivot varchar(max)='';
    Declare @ind_tmpTbl int; --Indicador de tabla temporal 1=tabla temporal global 0=Tabla fisica

    Create Table #pvt_column(
        pivot_col varchar(100)
    );

    Declare @column_agg table(
        opp_agg varchar(5),
        col_agg varchar(100)
    );

    IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(@table) AND type in (N'U'))
        Set @ind_tmpTbl=0;
    ELSE IF OBJECT_ID('tempdb..'+ltrim(rtrim(@table))) IS NOT NULL
        Set @ind_tmpTbl=1;

    IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(@new_table) AND type in (N'U')) OR 
        OBJECT_ID('tempdb..'+ltrim(rtrim(@new_table))) IS NOT NULL
    Begin
        Set @query='DROP TABLE '+@new_table+'';
        Exec (@query);
    End;

    Select @query='Select distinct '+@column+' From '+(case when @ind_tmpTbl=1 then 'tempdb.' else '' end)+@schema+'.'+@table+' where '+@column+' is not null;';
    Print @query;

    Insert into #pvt_column(pivot_col)
    Exec (@query)

    While charindex(',',@agg,1)>0
    Begin
        Select @aggDet=Substring(@agg,1,charindex(',',@agg,1)-1);

        Insert Into @column_agg(opp_agg,col_agg)
        Values(substring(@aggDet,1,charindex('(',@aggDet,1)-1),ltrim(rtrim(replace(substring(@aggDet,charindex('[',@aggDet,1),charindex(']',@aggDet,1)-4),')',''))));

        Set @agg=Substring(@agg,charindex(',',@agg,1)+1,len(@agg))

    End

    Declare cur_agg cursor read_only forward_only local static for
    Select 
        opp_agg,col_agg
    from @column_agg;

    Open cur_agg;

    Fetch Next From cur_agg
    Into @opp_agg,@col_agg;

    While @@fetch_status=0
    Begin

        Declare cur_col cursor read_only forward_only local static for
        Select 
            pivot_col 
        From #pvt_column;

        Open cur_col;

        Fetch Next From cur_col
        Into @pivot_col;

        While @@fetch_status=0
        Begin

            Select @query_col_pvt='isnull('+@opp_agg+'(case when '+@column+'='+quotename(@pivot_col,char(39))+' then '+@col_agg+
            ' else null end),0) as ['+lower(Replace(Replace(@opp_agg+'_'+convert(varchar(100),@pivot_col)+'_'+replace(replace(@col_agg,'[',''),']',''),' ',''),'&',''))+
                (case when @add_to_col_name is null then space(0) else '_'+isnull(ltrim(rtrim(@add_to_col_name)),'') end)+']'
            print @query_col_pvt
            Select @full_query_pivot=@full_query_pivot+@query_col_pvt+', '

            --print @full_query_pivot

            Fetch Next From cur_col
            Into @pivot_col;        

        End     

        Close cur_col;
        Deallocate cur_col;

        Fetch Next From cur_agg
        Into @opp_agg,@col_agg; 
    End

    Close cur_agg;
    Deallocate cur_agg;

    Select @full_query_pivot=substring(@full_query_pivot,1,len(@full_query_pivot)-1);

    Select @query='Select '+@sel_cols+','+@full_query_pivot+' into '+@new_table+' From '+(case when @ind_tmpTbl=1 then 'tempdb.' else '' end)+
    @schema+'.'+@table+' Group by '+@sel_cols+';';

    print @query;
    Exec (@query);

End;
GO

This is an example of execution:

Exec dbo.rs_pivot_table @schema=dbo,@table=##TEMPORAL1,@column=tip_liq,@agg='sum([val_liq]),avg([can_liq]),',@sel_cols='cod_emp,cod_con,tip_liq',@new_table=##TEMPORAL1PVT;

then Select * From ##TEMPORAL1PVT would return:

enter image description here

Java: object to byte[] and byte[] to object converter (for Tokyo Cabinet)

You can look at how Hector does this for Cassandra, where the goal is the same - convert everything to and from byte[] in order to store/retrieve from a NoSQL database - see here. For the primitive types (+String), there are special Serializers, otherwise there is the generic ObjectSerializer (expecting Serializable, and using ObjectOutputStream). You can, of course, use only it for everything, but there might be redundant meta-data in the serialized form.

I guess you can copy the entire package and make use of it.

deleting folder from java

The javadoc for File.delete()

public boolean delete()

Deletes the file or directory denoted by this abstract pathname. If this pathname >denotes a directory, then the directory must be empty in order to be deleted.

So a folder has to be empty or deleting it will fail. Your code currently fills the folder list with the top most folder first, followed by its sub folders. Since you iterrate through the list in the same way it will try to delete the top most folder before deleting its subfolders, this will fail.

Changing these line

    for(String filePath : folderList) {
        File tempFile = new File(filePath);
        tempFile.delete();
    }

to this

    for(int i = folderList.size()-1;i>=0;i--) {
        File tempFile = new File(folderList.get(i));
        tempFile.delete();
    }

should cause your code to delete the sub folders first.

The delete operation also returns false when it fails, so you can check this value to do some error handling if necessary.

How to Check whether Session is Expired or not in asp.net

Edit

You can use the IsNewSession property to check if the session was created on the request of the page

protected void Page_Load() 
{ 
   if (Context.Session != null) 
   { 
      if (Session.IsNewSession) 
      { 
         string cookieHeader = Request.Headers["Cookie"]; 
         if ((null != cookieHeader) && (cookieHeader.IndexOf("ASP.NET_SessionId") >= 0)) 
         { 
            Response.Redirect("sessionTimeout.htm"); 
         } 
      } 
   } 
}

pre

Store Userid in session variable when user logs into website and check on your master page or created base page form which other page gets inherits. Then in page load check that Userid is present and not if not then redirect to login page.

if(Session["Userid"]==null)
{
  //session expire redirect to login page 
}

How / can I display a console window in Intellij IDEA?

In IntelliJ IDEA 2016.1.1:

  1. View->Tool Windows->Debug (Alt+5)
  2. on top right of Debug Window, click "Restore Console View" which is only show a icon like below:

Restore Console View

URL rewriting with PHP

Although already answered, and author's intent is to create a front controller type app but I am posting literal rule for problem asked. if someone having the problem for same.

RewriteEngine On
RewriteRule ^([^/]+)/([^/]+)/([\d]+)$ $1?id=$3 [L]

Above should work for url picture.php/Some-text-goes-here/51. without using a index.php as a redirect app.

C# : 'is' keyword and checking for Not

This hasn't been mentioned yet. It works and I think it looks better than using !(child is IContainer)

if (part is IContainer is false)
{
    return;
}

New In C# 9.0

https://devblogs.microsoft.com/dotnet/welcome-to-c-9-0/#logical-patterns

if (part is not IContainer)
{
    return;
}

How to remove new line characters from data rows in mysql?

your syntax is wrong:

update mytable SET title = TRIM(TRAILING '\n' FROM title)

Addition:

If the newline character is at the start of the field:

update mytable SET title = TRIM(LEADING '\n' FROM title)

What are the benefits to marking a field as `readonly` in C#?

There can be a performance benefit in WPF, as it removes the need for expensive DependencyProperties. This can be especially useful with collections

Calling a Function defined inside another function in Javascript

Again, not a direct answer to the question, but was led here by a web search. Ended up exposing the inner function without using return, etc. by simply assigning it to a global variable.

var fname;

function outer() {
    function inner() {
        console.log("hi");
    }
    fname = inner;
}

Now just

fname();

What's the difference between an id and a class?

Class is used for multiple elements which have common attributes.Example if you want same color and font for both p and body tag use class attribute or in a division itself.

Id on the other hand is used for highlighting a single element attributes and used exclusively for a particular element only.For example we have an h1 tag with some attributes we would not want them to repeat in any other elements throughout the page.

It should be noted that if we use class and id both in an element,*id ovverides the class attributes.*Simply because id is exclusively for a single element

Refer the below example

<html>
<head>
<style>
    #html_id{
        color:aqua;
        background-color: black;

    }
    .html_class{
        color:burlywood;
        background-color: brown;
    }
</style>

   </head>
    <body>
<p  class="html_class">Lorem ipsum dolor sit amet consectetur adipisicing 
   elit. 
    Perspiciatis a dicta qui unde veritatis cupiditate ullam quibusdam! 
     Mollitia enim, 
    nulla totam deserunt ex nihil quod, eaque, sed facilis quos iste.</p>
    </body>
   </html>

We generate the output

Output

Linux bash: Multiple variable assignment

I think this might help...

In order to break down user inputted dates (mm/dd/yyyy) in my scripts, I store the day, month, and year into an array, and then put the values into separate variables as follows:

DATE_ARRAY=(`echo $2 | sed -e 's/\// /g'`)
MONTH=(`echo ${DATE_ARRAY[0]}`)
DAY=(`echo ${DATE_ARRAY[1]}`)
YEAR=(`echo ${DATE_ARRAY[2]}`)

In Oracle, is it possible to INSERT or UPDATE a record through a view?

There are two times when you can update a record through a view:

  1. If the view has no joins or procedure calls and selects data from a single underlying table.
  2. If the view has an INSTEAD OF INSERT trigger associated with the view.

Generally, you should not rely on being able to perform an insert to a view unless you have specifically written an INSTEAD OF trigger for it. Be aware, there are also INSTEAD OF UPDATE triggers that can be written as well to help perform updates.

conversion from infix to prefix

In Prefix expression operators comes first then operands : +ab[ oprator ab ]

Infix : (a–b)/c*(d + e – f / g)


Step 1: (a - b) = (- ab) [ '(' has highest priority ]

step 2: (d + e - f / g) = (d + e - / fg) [ '/' has highest priority ]

                       = (+ de - / fg )

          ['+','-' has same priority but left to right associativity]

                       = (- + de / fg)

Step 3: (-ab )/ c * (- + de / fg) = / - abc * (- + de / fg)

                                 = * / - abc - + de / fg 

Prefix : * / - abc - + de / fg

How to do a FULL OUTER JOIN in MySQL?

what'd you say about Cross join solution?

SELECT t1.*, t2.*
FROM table1 t1
INNER JOIN table2 t2 
ON 1=1;

Order columns through Bootstrap4

Since column-ordering doesn't work in Bootstrap 4 beta as described in the code provided in the revisited answer above, you would need to use the following (as indicated in the codeply 4 Flexbox order demo - alpha/beta links that were provided in the answer).

<div class="container">
<div class="row">
    <div class="col-3 col-md-6">
        <div class="card card-block">1</div>
    </div>
    <div class="col-6 col-md-12  flex-md-last">
        <div class="card card-block">3</div>
    </div>
    <div class="col-3 col-md-6 ">
        <div class="card card-block">2</div>
    </div>
</div>

Note however that the "Flexbox order demo - beta" goes to an alpha codebase, and changing the codebase to Beta (and running it) results in the divs incorrectly displaying in a single column -- but that looks like a codeply issue since cutting and pasting the code out of codeply works as described.

Convert varchar into datetime in SQL Server

I had luck with something similar:

Convert(DATETIME, CONVERT(VARCHAR(2), @Month) + '/' + CONVERT(VARCHAR(2), @Day)
+ '/' + CONVERT(VARCHAR(4), @Year))

AngularJS does not send hidden field value

I achieved this via -

 <p style="display:none">{{user.role="store_user"}}</p>

What is the use of WPFFontCache Service in WPF? WPFFontCache_v0400.exe taking 100 % CPU all the time this exe is running, why?

From MSDN:

The WPF Font Cache service shares font data between WPF applications. The first WPF application you run starts this service if the service is not already running. If you are using Windows Vista, you can set the "Windows Presentation Foundation (WPF) Font Cache 3.0.0.0" service from "Manual" (the default) to "Automatic (Delayed Start)" to reduce the initial start-up time of WPF applications.

There's no harm in disabling it, but WPF apps tend to start faster and load fonts faster with it running.
It is supposed to be a performance optimization. The fact that it is not in your case makes me suspect that perhaps your font cache is corrupted. To clear it, follow these steps:

  1. Stop the WPF Font Cache 4.0 service.
  2. Delete all of the WPFFontCache_v0400* files. In Windows XP, you'll find them in your C:\Documents and Settings\LocalService\Local Settings\Application Data\ folder.
  3. Start the service again.

TSQL DATETIME ISO 8601

For ISO 8601 format for Datetime & Datetime2, below is the recommendation from SQL Server. It does not support basic ISO 8601 format for datetime(yyyyMMddThhmmss).

DateTime

YYYY-MM-DDThh:mm:ss[.mmm]

YYYYMMDD[ hh:mm:ss[.mmm]]

Examples:

  1. 2004-05-23T14:25:10

  2. 2004-05-23T14:25:10.487

Datetime2

YYYY-MM-DDThh:mm:ss[.nnnnnnn]

YYYY-MM-DDThh:mm:ss[.nnnnnnn] Examples:

  1. 2004-05-23T14:25:10

  2. 2004-05-23T14:25:10.8849926

You can convert them using 126 option

--Datetime

DECLARE @table Table(ExtendedDate DATETIME, BasicDate Datetime)

DECLARE @ExtendedDate VARCHAR(30) = '2020-07-01T08:39:17' , @BasicDate VARCHAR(30) = '2009-01-23T10:53:21.000'

INSERT INTO @table(ExtendedDate, BasicDate)
SELECT convert(datetime,@ExtendedDate,126) ,convert(datetime,@BasicDate,126)

SELECT * FROM @table
go

-- Datetime2

DECLARE @table Table(ExtendedDate DATETIME2, BasicDate Datetime2)

DECLARE @ExtendedDate VARCHAR(30) = '2000-01-14T13:42:00.0000000' , @BasicDate VARCHAR(30) = '2009-01-23T10:53:21.0000000'

INSERT INTO @table(ExtendedDate, BasicDate)
SELECT convert(datetime2,@ExtendedDate,126) ,convert(datetime2,@BasicDate,126)

SELECT * FROM @table
go

Datetime

+-------------------------+-------------------------+
|      ExtendedDate       |        BasicDate        |
+-------------------------+-------------------------+
| 2020-07-01 08:39:17.000 | 2009-01-23 10:53:21.000 |
+-------------------------+-------------------------+

Datetime2


+-----------------------------+-----------------------------+
|        ExtendedDate         |          BasicDate          |
+-----------------------------+-----------------------------+
| 2000-01-14 13:42:00.0000000 | 2009-01-23 10:53:21.0000000 |
+-----------------------------+-----------------------------+

How do I resolve "HTTP Error 500.19 - Internal Server Error" on IIS7.0

If you are using a new, dedicated, user account... It is also worth checking that the password for that account has not expired, as that will also cause this 500.19 permissions issue.

How enable auto-format code for Intellij IDEA?

This can also be achieved by Ctrl+WindowsBtn+Alt+L. This will be important to some people,because in some Virtual Machines, Ctrl+Alt+L can log you out.

Excel Date to String conversion

In some contexts using a ' character beforehand will work, but if you save to CSV and load again this is impossible.

'01/01/2010 14:30:00

How to extend a class in python?

Another way to extend (specifically meaning, add new methods, not change existing ones) classes, even built-in ones, is to use a preprocessor that adds the ability to extend out of/above the scope of Python itself, converting the extension to normal Python syntax before Python actually gets to see it.

I've done this to extend Python 2's str() class, for instance. str() is a particularly interesting target because of the implicit linkage to quoted data such as 'this' and 'that'.

Here's some extending code, where the only added non-Python syntax is the extend:testDottedQuad bit:

extend:testDottedQuad
def testDottedQuad(strObject):
    if not isinstance(strObject, basestring): return False
    listStrings = strObject.split('.')
    if len(listStrings) != 4: return False
    for strNum in listStrings:
        try:    val = int(strNum)
        except: return False
        if val < 0: return False
        if val > 255: return False
    return True

After which I can write in the code fed to the preprocessor:

if '192.168.1.100'.testDottedQuad():
    doSomething()

dq = '216.126.621.5'
if not dq.testDottedQuad():
    throwWarning();

dqt = ''.join(['127','.','0','.','0','.','1']).testDottedQuad()
if dqt:
    print 'well, that was fun'

The preprocessor eats that, spits out normal Python without monkeypatching, and Python does what I intended it to do.

Just as a c preprocessor adds functionality to c, so too can a Python preprocessor add functionality to Python.

My preprocessor implementation is too large for a stack overflow answer, but for those who might be interested, it is here on GitHub.

What do I need to do to get Internet Explorer 8 to accept a self signed certificate?

I had the same issue while working with web services. Here Microsoft has a (long) walk-thru showing you how to install stuff on the client to basically say that your self-signed cert is ok. In the end, I just spent the $30 and bought a full certificate from Godaddy.com.

P.S. I know that you can code around the error message but we didn't want to do that for testing reasons.

Proper way to initialize a C# dictionary with values?

I can't reproduce this issue in a simple .NET 4.0 console application:

static class Program
{
    static void Main(string[] args)
    {
        var myDict = new Dictionary<string, string>
        {
            { "key1", "value1" },
            { "key2", "value2" }
        };

        Console.ReadKey();
    }
}

Can you try to reproduce it in a simple Console application and go from there? It seems likely that you're targeting .NET 2.0 (which doesn't support it) or client profile framework, rather than a version of .NET that supports initialization syntax.

How to access the contents of a vector from a pointer to the vector in C++?

There are a lot of solutions. For example you can use at() method.

*I assumed that you a looking for equivalent to [] operator.

how to return a char array from a function in C

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
char *substring(int i,int j,char *ch)
{
    int n,k=0;
    char *ch1;
    ch1=(char*)malloc((j-i+1)*1);
    n=j-i+1;

    while(k<n)
    {
        ch1[k]=ch[i];
        i++;k++;
    }

    return (char *)ch1;
}

int main()
{
    int i=0,j=2;
    char s[]="String";
    char *test;

    test=substring(i,j,s);
    printf("%s",test);
    free(test); //free the test 
    return 0;
}

This will compile fine without any warning

  1. #include stdlib.h
  2. pass test=substring(i,j,s);
  3. remove m as it is unused
  4. either declare char substring(int i,int j,char *ch) or define it before main

Sending email with attachments from C#, attachments arrive as Part 1.2 in Thunderbird

Simple code to send email with attachement.

source: http://www.coding-issues.com/2012/11/sending-email-with-attachments-from-c.html

using System.Net;
using System.Net.Mail;

public void email_send()
{
    MailMessage mail = new MailMessage();
    SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");
    mail.From = new MailAddress("your [email protected]");
    mail.To.Add("[email protected]");
    mail.Subject = "Test Mail - 1";
    mail.Body = "mail with attachment";

    System.Net.Mail.Attachment attachment;
    attachment = new System.Net.Mail.Attachment("c:/textfile.txt");
    mail.Attachments.Add(attachment);

    SmtpServer.Port = 587;
    SmtpServer.Credentials = new System.Net.NetworkCredential("your [email protected]", "your password");
    SmtpServer.EnableSsl = true;

    SmtpServer.Send(mail);

}

How to convert a Datetime string to a current culture datetime string

DateTimeFormatInfo usDtfi = new CultureInfo("en-US", false).DateTimeFormat;
DateTimeFormatInfo ukDtfi = new CultureInfo("en-GB", false).DateTimeFormat;
string result = Convert.ToDateTime("12/01/2011", usDtfi).ToString(ukDtfi.ShortDatePattern);

This will do the trick ^^

In Python try until no error

Here is a short piece of code I use to capture the error as a string. Will retry till it succeeds. This catches all exceptions but you can change this as you wish.

start = 0
str_error = "Not executed yet."
while str_error:
    try:
        # replace line below with your logic , i.e. time out, max attempts
        start = raw_input("enter a number, 0 for fail, last was {0}: ".format(start))
        new_val = 5/int(start)
        str_error=None
    except Exception as str_error:
         pass

WARNING: This code will be stuck in a forever loop until no exception occurs. This is just a simple example and MIGHT require you to break out of the loop sooner or sleep between retries.

How to modify a text file?

The fileinput module of the Python standard library will rewrite a file inplace if you use the inplace=1 parameter:

import sys
import fileinput

# replace all occurrences of 'sit' with 'SIT' and insert a line after the 5th
for i, line in enumerate(fileinput.input('lorem_ipsum.txt', inplace=1)):
    sys.stdout.write(line.replace('sit', 'SIT'))  # replace 'sit' and write
    if i == 4: sys.stdout.write('\n')  # write a blank line after the 5th line

Downgrade npm to an older version

Before doing that Download Node Js 8.11.3 from the URL: download

Open command prompt and run this:

npm install -g [email protected]

use this version this is the stable version which works along with cordova 7.1.0

for installing cordova use : • npm install -g [email protected]

• Run command

• Cordova platform remove android (if you have old android code or code is having some issue)

• Cordova platform add android : for building android app in cordova Running: Corodva run android

Parse Json string in C#

json:
[{"ew":"vehicles","hws":["car","van","bike","plane","bus"]},{"ew":"countries","hws":["America","India","France","Japan","South Africa"]}]

c# code: to take only a single value, for example the word "bike".

//res=[{"ew":"vehicles","hws":["car","van","bike","plane","bus"]},{"ew":"countries","hws":["America","India","France","Japan","South Africa"]}]

         dynamic stuff1 = Newtonsoft.Json.JsonConvert.DeserializeObject(res);
         string Text = stuff1[0].hws[2];
         Console.WriteLine(Text);

output:

bike

How to create python bytes object from long hex string?

Try the binascii module

from binascii import unhexlify
b = unhexlify(myhexstr)

Git in Visual Studio - add existing project?

Here is how to do it in Visual Studio 2015.

  1. Open the project and go to Tools >> Options >> "Source Control" tab and select "Git" as your source control. enter image description here

  2. Go to File Menu and select "Add to source control".

What this does is essentially execute "git init" by visual studio creating all the bells and whistles (setup ignore files accordingly like ignore user specific files, temporary files, directory etc).

Essentially your git repository has been created correct locally (this is the major step with VS project since this folder contains a lot of files that we want to ignore).

Now you can connect this git repository to any other git like GitHub, BitBucket etc in git bash (outside Visual Studio).

I start Git Bash session now in this working directory and since I use BitBucket, I follow the instructions given there (just copy the lines below from there).

git remote add origin https://[email protected]/yourusername/hookdemo.git

git push -u origin master

That's it.

Afterwards you can manage the repository on git command line itself since its setup properly now.

Why maven? What are the benefits?

This should have been a comment, but it wasn't fitting in a comment length, so I posted it as an answer.

All the benefits mentioned in other answers are achievable by simpler means than using maven. If, for-example, you are new to a project, you'll anyway spend more time creating project architecture, joining components, coding than downloading jars and copying them to lib folder. If you are experienced in your domain, then you already know how to start off the project with what libraries. I don't see any benefit of using maven, especially when it poses a lot of problems while automatically doing the "dependency management".

I only have intermediate level knowledge of maven, but I tell you, I have done large projects(like ERPs) without using maven.

How to convert Strings to and from UTF8 byte arrays in Java

For decoding a series of bytes to a normal string message I finally got it working with UTF-8 encoding with this code:

/* Convert a list of UTF-8 numbers to a normal String
 * Usefull for decoding a jms message that is delivered as a sequence of bytes instead of plain text
 */
public String convertUtf8NumbersToString(String[] numbers){
    int length = numbers.length;
    byte[] data = new byte[length];

    for(int i = 0; i< length; i++){
        data[i] = Byte.parseByte(numbers[i]);
    }
    return new String(data, Charset.forName("UTF-8"));
}

MongoDB inserts float when trying to insert integer

db.data.update({'name': 'zero'}, {'$set': {'value': NumberInt(0)}})

You can also use NumberLong.

NoSQL Use Case Scenarios or WHEN to use NoSQL

It really is an "it depends" kinda question. Some general points:

  • NoSQL is typically good for unstructured/"schemaless" data - usually, you don't need to explicitly define your schema up front and can just include new fields without any ceremony
  • NoSQL typically favours a denormalised schema due to no support for JOINs per the RDBMS world. So you would usually have a flattened, denormalized representation of your data.
  • Using NoSQL doesn't mean you could lose data. Different DBs have different strategies. e.g. MongoDB - you can essentially choose what level to trade off performance vs potential for data loss - best performance = greater scope for data loss.
  • It's often very easy to scale out NoSQL solutions. Adding more nodes to replicate data to is one way to a) offer more scalability and b) offer more protection against data loss if one node goes down. But again, depends on the NoSQL DB/configuration. NoSQL does not necessarily mean "data loss" like you infer.
  • IMHO, complex/dynamic queries/reporting are best served from an RDBMS. Often the query functionality for a NoSQL DB is limited.
  • It doesn't have to be a 1 or the other choice. My experience has been using RDBMS in conjunction with NoSQL for certain use cases.
  • NoSQL DBs often lack the ability to perform atomic operations across multiple "tables".

You really need to look at and understand what the various types of NoSQL stores are, and how they go about providing scalability/data security etc. It's difficult to give an across-the-board answer as they really are all different and tackle things differently.

For MongoDb as an example, check out their Use Cases to see what they suggest as being "well suited" and "less well suited" uses of MongoDb.

How to enable explicit_defaults_for_timestamp?

For me it worked to add the phrase "explicit_defaults_for_timestamp = ON" without quotes into the config file my.ini.

Make sure you add this phrase right underneath the [mysqld] statement in the config file.

You will find my.ini under C:\ProgramData\MySQL\MySQL Server 5.7 if you had conducted the default installation of MySQL.

Distribution certificate / private key not installed

In my case Xcode was not accessing certificates from the keychain, I followed these steps:

  1. delete certificates from the keychain.
  2. restart the mac.
  3. generate new certificates.
  4. install new certificates.
  5. clean build folder.
  6. build project.
  7. again clean build folder.
  8. archive now. It works That's it.

How to download and save a file from Internet using Java?

It's an old question but here is a concise, readable, JDK-only solution with properly closed resources:

static long download(String sourceUrl, String targetFileName) throws Exception {
    try (InputStream in = URI.create(sourceUrl).toURL().openStream()) {
        return Files.copy(in, Paths.get(targetFileName));
    }
}

Two lines of code and no dependencies.

Here's a complete file downloader example program with output, error checking, and command line argument checks:

package so.downloader;

import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URI;
import java.nio.file.Files;
import java.nio.file.Paths;

public class Application {
    public static void main(String[] args) throws MalformedURLException, IOException {
        if (2 != args.length) {
            System.out.println(String.format("USAGE: java -jar so-downloader.jar <source-URL> <target-filename>"));
            System.exit(1);
        }

        String sourceUrl = args[0];
        String targetFilename = args[1];

        long bytesDownloaded = download(sourceUrl, targetFilename);

        System.out.println(String.format("Downloaded %d bytes from %s to %s.", bytesDownloaded, sourceUrl, targetFilename));
    }

    static long download(String sourceUrl, String targetFileName) throws MalformedURLException, IOException {
        try (InputStream in = URI.create(sourceUrl).toURL().openStream()) {
            return Files.copy(in, Paths.get(targetFileName));
        }
    }

}

As noted in the so-downloader repository README:

To run file download program:

java -jar so-downloader.jar <source-URL> <target-filename>

for example:

java -jar so-downloader.jar https://github.com/JanStureNielsen/so-downloader/archive/main.zip so-downloader-source.zip

How do I commit case-sensitive only filename changes in Git?

Git has a configuration setting that tells it whether to be case sensitive or insensitive: core.ignorecase. To tell Git to be case-senstive, simply set this setting to false. (Be careful if you have already pushed the files, then you should first move them given the other answers).

git config core.ignorecase false

Documentation

From the git config documentation:

core.ignorecase

If true, this option enables various workarounds to enable git to work better on filesystems that are not case sensitive, like FAT. For example, if a directory listing finds makefile when git expects Makefile, git will assume it is really the same file, and continue to remember it as Makefile.

The default is false, except git-clone(1) or git-init(1) will probe and set core.ignorecase true if appropriate when the repository is created.

Case-insensitive file-systems

The two most popular operating systems that have case-insensitive file systems that I know of are

  • Windows
  • OS X

Curl setting Content-Type incorrectly

I think you want to specify

-H "Content-Type:text/xml"

with a colon, not an equals.

How do I find the index of a character within a string in C?

void myFunc(char* str, char c)
{
    char* ptr;
    int index;

    ptr = strchr(str, c);
    if (ptr == NULL)
    {
        printf("Character not found\n");
        return;
    }

    index = ptr - str;

    printf("The index is %d\n", index);
    ASSERT(str[index] == c);  // Verify that the character at index is the one we want.
}

This code is currently untested, but it demonstrates the proper concept.

How to open a page in a new window or tab from code-behind

You can use scriptmanager.registerstartupscript to call a JavaScript function.

Inside that function, you can open a new window.

Jmeter - get current date and time

it seems to be the java SimpleDateFormat : http://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html

here are some tests i did around 11:30pm on the 20th of May 2015

${__time(dd-mmm-yyyy HHmmss)} 20-032-2015 233224
${__time(d-MMM-yyyy hhmmss)}  20-May-2015 113224
${__time(dd-m-yyyy hhmmss)}   20-32-2015 113224
${__time(D-M-yyyy hhmmss)}    140-5-2015 113224
${__time(DD-MM-yyyy)}         140-05-2015

Run react-native on android emulator

Try

  • brew cask install android-platform-tools
  • adb reverse tcp:9090 tcp:9090
  • run the app

Text inset for UITextField?

Swift 5 version of Christopher's answer with extra usage sample

import UIKit

private class InsetTextField: UITextField {
    var insets: UIEdgeInsets

    init(insets: UIEdgeInsets) {
        self.insets = insets
        super.init(frame: .zero)
    }

    required init(coder aDecoder: NSCoder) {
        fatalError("not intended for use from a NIB")
    }

    // placeholder position
    override func textRect(forBounds bounds: CGRect) -> CGRect {
         return super.textRect(forBounds: bounds.inset(by: insets))
    }
 
    // text position
    override func editingRect(forBounds bounds: CGRect) -> CGRect {
         return super.editingRect(forBounds: bounds.inset(by: insets))
    }
}

extension UITextField {

    class func textFieldWithInsets(insets: UIEdgeInsets) -> UITextField {
        return InsetTextField(insets: insets)
    }

}

Usage: -

class ViewController: UIViewController {

  private let passwordTextField: UITextField = {

        let textField = UITextField.textFieldWithInsets(insets: UIEdgeInsets(top: 10, left: 15, bottom: 10, right: 15))
     // ---
   
        return textField
    }()

}

Which icon sizes should my Windows application's icon include?

The Microsoft UX icon guideline says:

"Application icons and Control Panel items: The full set includes 16x16, 32x32, 48x48, and 256x256 (code scales between 32 and 256)."

To me this implies (but does not explicitly state, unfortunately) that you should supply those 4 sizes.

Additional details regarding color formats, which you may also find useful:

  • "Icon files require 8-bit and 4-bit palette versions as well, to support the default setting in a remote desktop."

  • "Only a 32-bit copy of the 256x256 pixel image should be included, and only the 256x256 pixel image should be compressed [as PNG] to keep the file size down."

How to handle change text of span

You could use the function that changes the text of span1 to change the text of the others.

As a work around, if you really want it to have a change event, then don't asign text to span 1. Instead asign an input variable in jQuery, write a change event to it, and whever ur changing the text of span1 .. instead change the value of your input variable, thus firing change event, like so:

var spanChange = $("<input />");
function someFuncToCalculateAndSetTextForSpan1() {
    //  do work
    spanChange.val($newText).change();
};

$(function() {
    spanChange.change(function(e) {
        var $val = $(this).val(),
            $newVal = some*calc-$val;
        $("#span1").text($val);
        $("#spanWhatever").text($newVal);
    });
});

Though I really feel this "work-around", while useful in some aspects of creating a simple change event, is very overextended, and you'd best be making the changes to other spans at the same time you change span1.

Untrack files from git temporarily

I am assuming that you are asking how to remove ALL the files in the build folder or the bin folder, Rather than selecting each files separately.

You can use this command:

git rm -r -f /build\*

Make sure that you are in the parent directory of the build directory.
This command will, recursively "delete" all the files which are in the bin/ or build/ folders. By the word delete I mean that git will pretend that those files are "deleted" and those files will not be tracked. The git really marks those files to be in delete mode.

Do make sure that you have your .gitignore ready for upcoming commits.
Documentation : git rm

Get position/offset of element relative to a parent container?

Add the offset of the event to the parent element offset to get the absolute offset position of the event.

An example :

HTMLElement.addEventListener('mousedown',function(e){

    var offsetX = e.offsetX;
    var offsetY = e.offsetY;

    if( e.target != this ){ // 'this' is our HTMLElement

        offsetX = e.target.offsetLeft + e.offsetX;
        offsetY = e.target.offsetTop + e.offsetY;

    }
}

When the event target is not the element which the event was registered to, it adds the offset of the parent to the current event offset in order to calculate the "Absolute" offset value.

According to Mozilla Web API: "The HTMLElement.offsetLeft read-only property returns the number of pixels that the upper left corner of the current element is offset to the left within the HTMLElement.offsetParent node."

This mostly happens when you registered an event on a parent which is containing several more children, for example: a button with an inner icon or text span, an li element with inner spans. etc...

Set TextView text from html-formatted string resource in XML

I have another case when I have no chance to put CDATA into the xml as I receive the string HTML from a server.

Here is what I get from a server:

<p>The quick brown&nbsp;<br />
fox jumps&nbsp;<br />
 over the lazy dog<br />
</p>

It seems to be more complicated but the solution is much simpler.

private TextView textView;

protected void onCreate(Bundle savedInstanceState) { 
.....
textView = (TextView) findViewById(R.id.text); //need to define in your layout
String htmlFromServer = getHTMLContentFromAServer(); 
textView.setText(Html.fromHtml(htmlFromServer).toString());

}

Hope it helps!
Linh

How to compare Boolean?

.equals(false) will be slower because you are calling a virtual method on an object rather than using faster syntax and rather unexpected by most of the programmers because code standards that are generally used don't really assume you should be doing that check via .equals(false) method.

Set Memory Limit in htaccess

In your .htaccess you can add:

PHP 5.x

<IfModule mod_php5.c>
    php_value memory_limit 64M
</IfModule>

PHP 7.x

<IfModule mod_php7.c>
    php_value memory_limit 64M
</IfModule>

If page breaks again, then you are using PHP as mod_php in apache, but error is due to something else.

If page does not break, then you are using PHP as CGI module and therefore cannot use php values - in the link I've provided might be solution but I'm not sure you will be able to apply it.

Read more on http://support.tigertech.net/php-value

How to download an entire directory and subdirectories using wget?

use the command

wget -m www.ilanni.com/nexus/content/

Jquery get form field value

_x000D_
_x000D_
$("form").submit(function(event) {_x000D_
    _x000D_
      var firstfield_value  = event.currentTarget[0].value;_x000D_
     _x000D_
      var secondfield_value = event.currentTarget[1].value; _x000D_
     _x000D_
      alert(firstfield_value);_x000D_
      alert(secondfield_value);_x000D_
      event.preventDefault(); _x000D_
     });
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<form action="" method="post" >_x000D_
<input type="text" name="field1" value="value1">_x000D_
<input type="text" name="field2" value="value2">_x000D_
</form>
_x000D_
_x000D_
_x000D_

Google Chrome redirecting localhost to https

Another option would be to use something like https://github.com/rchampourlier/tunnelss

Sure it added another dependency / setup, but it also enables testing of https in dev, which could be nice.

I use RVM however to get tunnelss working I had to use sudo gem install tunnelss and sudo tunnelss

$.focus() not working

Some of the answers here suggest using setTimeout to delay the process of focusing on the target element. One of them mentions that the target is inside a modal dialog. I cannot comment further on the correctness of the setTimeoutsolution without knowing the specific details of where it was used. However, I thought I should provide an answer here to help out people who run into this thread just as I did

The simple fact of the matter is that you cannot focus on an element which is not yet visible. If you run into this problem ensure that the target is actually visible when the attempt to focus it is made. In my own case I was doing something along these lines

$('#elementid').animate({left:0,duration:'slow'});
$('#elementid').focus();

This did not work. I only realized what was going on when I executed $('#elementid').focus()` from the console which did work. The difference - in my code above the target there is no certainty that the target will infact be visible since the animation may not be complete. And there lies the clue

$('#elementid').animate({left:0,duration:'slow',complete:focusFunction});

function focusFunction(){$('#elementid').focus();}

works just as expected. I too had initially put in a setTimeout solution and it worked too. However, an arbitrarily chosen timeout is bound to break the solution sooner or later depending on how slowly the host device goes about the process of ensuring that the target element is visible.

How to use SharedPreferences in Android to store, fetch and edit values

Singleton Shared Preferences Class. it may help for others in future.

import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;

public class SharedPref
{
    private static SharedPreferences mSharedPref;
    public static final String NAME = "NAME";
    public static final String AGE = "AGE";
    public static final String IS_SELECT = "IS_SELECT";

    private SharedPref()
    {

    }

    public static void init(Context context)
    {
        if(mSharedPref == null)
            mSharedPref = context.getSharedPreferences(context.getPackageName(), Activity.MODE_PRIVATE);
    }

    public static String read(String key, String defValue) {
        return mSharedPref.getString(key, defValue);
    }

    public static void write(String key, String value) {
        SharedPreferences.Editor prefsEditor = mSharedPref.edit();
        prefsEditor.putString(key, value);
        prefsEditor.commit();
    }

    public static boolean read(String key, boolean defValue) {
        return mSharedPref.getBoolean(key, defValue);
    }

    public static void write(String key, boolean value) {
        SharedPreferences.Editor prefsEditor = mSharedPref.edit();
        prefsEditor.putBoolean(key, value);
        prefsEditor.commit();
    }

    public static Integer read(String key, int defValue) {
        return mSharedPref.getInt(key, defValue);
    }

    public static void write(String key, Integer value) {
        SharedPreferences.Editor prefsEditor = mSharedPref.edit();
        prefsEditor.putInt(key, value).commit();
    }
}

Simply call SharedPref.init() on MainActivity once

SharedPref.init(getApplicationContext());

To Write data

SharedPref.write(SharedPref.NAME, "XXXX");//save string in shared preference.
SharedPref.write(SharedPref.AGE, 25);//save int in shared preference.
SharedPref.write(SharedPref.IS_SELECT, true);//save boolean in shared preference.

To Read Data

String name = SharedPref.read(SharedPref.NAME, null);//read string in shared preference.
int age = SharedPref.read(SharedPref.AGE, 0);//read int in shared preference.
boolean isSelect = SharedPref.read(SharedPref.IS_SELECT, false);//read boolean in shared preference.

Get bottom and right position of an element

Instead of

var bottom = $(window).height() - link.height();
bottom = offset.top - bottom;

Why aren't you doing

var bottom = $(window).height() - top - link.height();

Edit: Your mistake is that you're doing

bottom = offset.top - bottom;

instead of

bottom = bottom - offset.top; // or bottom -= offset.top;

CSS @font-face not working in ie

Change as per below

@font-face {
    font-family: "Futura";
    src: url("../fonts/Futura_Medium_BT.eot"); /* IE */
    src: local("Futura"), url( "../fonts/Futura_Medium_BT.ttf" ) format("truetype"); /* non-IE */  
}

body nav {
     font-family: "Futura";
    font-size:1.2em;
    height: 40px;
}

Select <a> which href ends with some string

$("a[href*='id=ABC']").addClass('active_jquery_menu');

initialize a numpy array

I'd suggest defining shape first. Then iterate over it to insert values.

big_array= np.zeros(shape = ( 6, 2 ))
for it in range(6):
    big_array[it] = (it,it) # For example

>>>big_array

array([[ 0.,  0.],
       [ 1.,  1.],
       [ 2.,  2.],
       [ 3.,  3.],
       [ 4.,  4.],
       [ 5.,  5.]])