Application keeps stoping due to locationManager

I am new in android development and creating an app to place my live location on map...but I don't know why this application keeps stopping. I think this is due to the locationManager because when I commented that part..then the app didn't stop.

please help me regarding this error.....

Below is the code for the project>>

package com.example.thefinalapplication;

import ...

import java.util.Arrays;

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {

private GoogleMap mMap;
private LocationListener locationListener;
private LocationManager locationManager=null;
private final int MIN_TIME = 2000;
private final int MIN_DIST = 5;

private DatabaseReference databaseReference;
private EditText editTextLongitude;
private EditText editTextLatitude;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_maps);
    // Obtain the SupportMapFragment and get notified when the map is ready to be used.
    SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.map);
    mapFragment.getMapAsync(this);


    ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, PackageManager.PERMISSION_GRANTED);
    ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, PackageManager.PERMISSION_GRANTED);

    editTextLatitude = (EditText) findViewById(R.id.editText);
    editTextLongitude = (EditText) findViewById(R.id.editText2);


    databaseReference = FirebaseDatabase.getInstance().getReference("Location");
    databaseReference.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot snapshot) {
            try {

                String databaseLatitudeString=snapshot.child("Latitude").getValue().toString().substring(1,snapshot.child("Latitude").getValue().toString().length()-1);
                String databaseLongitudeString=snapshot.child("Longitude").getValue().toString().substring(1,snapshot.child("Longitude").getValue().toString().length()-1);

                String[] stringLat = databaseLatitudeString.split(", ");
                Arrays.sort(stringLat);
                String latitude = stringLat[stringLat.length-1].split("=")[1];

                String[] stringLong = databaseLongitudeString.split(", ");
                Arrays.sort(stringLong);
                String longitude = stringLong[stringLong.length-1].split("=")[1];

                for (DataSnapshot LSnapshot: snapshot.getChildren()) {
                    LSnapshot.getRef().removeValue();
                }



                mMap.clear();
                float zoomLevel = 16.0f; //This goes up to 21

                LatLng latLng = new LatLng(Double.parseDouble(latitude), Double.parseDouble(longitude));

                mMap.addMarker(new MarkerOptions().position(latLng).title(latitude + " , " + longitude));

                mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng, zoomLevel));

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

        }

        @Override
        public void onCancelled(@NonNull DatabaseError error) {

        }
    });


}


@Override
public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;

    // Add a marker in Sydney and move the camera
    //      LatLng sydney = new LatLng(-34, 151);
    //      mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));
    //      mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));


    locationListener = new LocationListener() {
        @Override
        public void onLocationChanged(@NonNull Location location) {
            try {
                editTextLatitude.setText(Double.toString(location.getLatitude()));
                editTextLongitude.setText(Double.toString(location.getLongitude()));


                databaseReference.child("Latitude").push().setValue(editTextLatitude.getText().toString());
                databaseReference.child("Longitude").push().setValue(editTextLongitude.getText().toString());



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

    locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        // TODO: Consider calling
        //    ActivityCompat#requestPermissions
        // here to request the missing permissions, and then overriding
        //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
        //                                          int[] grantResults)
        // to handle the case where the user grants the permission. See the documentation
        // for ActivityCompat#requestPermissions for more details.
        return;
    }
    try {
        locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME, MIN_DIST, locationListener);
        locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,MIN_TIME,MIN_DIST,locationListener);
    }
    catch(Exception e){
        e.printStackTrace();
    }


}

}

even when I am implementing a basic live location app without database. Then it is also keeps stopping..

Help !!