The last know location could be null. So you need a further check for this, then ask for a quick update:

   if(location == null){
            String provider = locationManager.getBestProvider(criteria, true);
            if (provider != null){
                locationManager.requestLocationUpdates(provider, 0, 0, singeUpdateListener, context.getMainLooper()); 
            }else {
                Log.e("TAG", No location set");             
            }
    }

class variable:

protected LocationListener singeUpdateListener = new LocationListener() {
        public void onLocationChanged(Location location) {
            String lati = Double.toString(location.getLatitude());
            String longi = Double.toString(location.getLongitude());
            locationManager.removeUpdates(singeUpdateListener);
        }

        public void onStatusChanged(String provider, int status, Bundle extras) {}
        public void onProviderEnabled(String provider) {}
        public void onProviderDisabled(String provider) {}
      };

First you need to define a LocationListener to handle location changes.

int LOCATION_REFRESH_TIME = 15000; // 15 seconds to update
int LOCATION_REFRESH_DISTANCE = 500; // 500 meters to update

....

private final LocationListener mLocationListener = new LocationListener() {
    @Override
    public void onLocationChanged(final Location location) {
        //your code here
    }
};

Then get the LocationManager and ask for location updates

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

    mLocationManager = (LocationManager) getSystemService(LOCATION_SERVICE);

    mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, LOCATION_REFRESH_TIME,
            LOCATION_REFRESH_DISTANCE, mLocationListener);
}

And finally make sure that you have added the permission on the Manifest,

For using only network based location use this one

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

For GPS based location, this one

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

There is one other way to achieve it using java only.

You can use selenium+PhantomJS to hit "https://mycurrentlocation.net/". This website by default will load you current location and you can read the data on this website using Selenium API.

PhantomJS is an invisible browser, it can open any website in invisible mode and read data from the same.

Hope this helps.

Create a data member of Location class.

  public static Location mLocation;

use OnMyLocationChangeListener on Map

   mMap.setOnMyLocationChangeListener(new   GoogleMap.OnMyLocationChangeListener() {
        @Override
        public void onMyLocationChange(Location location) {
            mLocation = location;
                displayCurrentLocation();
        }
    });

      public  void displayCurrentLocation(){
    CameraPosition cameraPosition = new CameraPosition.Builder().
            target(new LatLng(mLocation.getLatitude(), mLocation.getLongitude())).
            tilt(60).
            zoom(15).
            bearing(0).
            build();
       mMap.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
}

hope it will works.

You should use the last Google API to location. First, you connect with this API like this:

GoogleApiClient googleApiClient = new GoogleApiClient.Builder(this)
                    .addApi(LocationServices.API)
                    .addConnectionCallbacks(locationClientCallback)
                    .addOnConnectionFailedListener(locationClientCallback)
                    .build();

if (!(googleApiClient.isConnected() || googleApiClient.isConnecting())) {
       googleApiClient.connect();
}

Now, in your locationClientCallback you receive if the API is connected or not.

private class LocationClientCallback implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {

        @Override
        public void onLocationChanged(Location location) {
            if (location == null) {
                return;
            }

            // YOU HAVE YOUR POSITION

        }

        @Override
        public void onConnectionFailed(ConnectionResult arg0) {
            // CONNECTION FAILED
        }

        @Override
        public void onConnected(Bundle arg0) {
            // GOOGLE API CONNECTED 


            // MAKE A REQUEST FOR LOCATIONS
            LocationRequest request = LocationRequest.create();
            request.setSmallestDisplacement(0);
            request.setInterval(5000);
            request.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
            LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient, request, this);

        }

        @Override
        public void onConnectionSuspended(int i) {
            // CONNECTION SUSPENDED

        }


    }

And in the callbacks you receive the positions and other events. In onConnected event you should request for locations to Google API Client.

Hope it helps you!!

getSystemService() is a method of the Context class. Your class does not subclass Context. Generally you would use getSystemService() in an Activity (which is a subclass of Context).

The biggest DB with WiFi-to-location is Skyhook wireless. You can get the SDK from here : Skyhook Location SDK

It has not fully coverage, but it's the best in my opinion(Google and Apple use it).