firebaseThirdExample.java

FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference myRef = database.getReference("message");
myRef.addValueEventListener(new ValueEventListener() {
  @Override
	public void onDataChange(DataSnapshot dataSnapshot) {
	  Log.i("MyApp","Data changed");
	}

	@Override
	public void onCancelled(DatabaseError databaseError) {
	  Log.i("MyApp","Data canceled");
	}
});