class StoreImage implements ICachable<StoreImage> {

  @Override
  public long getByteSize() {
    return data.length;
  }

}

class TestStoreImage {

  private static final String IMG_STRING;
  private static final String IMG_DATA;
  private static final long IMG_ID0;
  private static final long IMG_ID1;
  private BufferedImage img;
  @Mock
  private StoreImage mockedImg0;
  @Mock
  private StoreImage mockedImg1;

  @Test
  public void testGetByteSize() {

    StoreImage uut = new StoreImage(IMG_ID1, IMG_DATA.getBytes(), ImageSizePreset.ICON.getSize());
    assertEquals(IMG_DATA.getBytes().length, uut.getByteSize());
  }

}