@Test
public void getTileRelativeFilenameString() {

    final MapTile tile = new MapTile(1, 13, 12);
    doReturn(tile.getY()).when(toTest).getYinTMSFormat(anyInt(), anyInt());
    final String result = toTest.getTileRelativeFilenameString(tile);
    assertEquals(
            tileName + "/" + tile.getZoomLevel() + "/" +
                    tile.getX() + "/" + toTest.getYinTMSFormat(tile.getZoomLevel(), tile.getY()) + fileEnding,
            result);
}