@Test
public void testCompareRowKeyWrappers() {

  assertEquals(0, new RowKeyWrapper(null).compareTo(new RowKeyWrapper(null)));
  RowKeyWrapper rowKey = new RowKeyWrapper(ByteString.copyFromUtf8("a"));
  assertEquals(-1, rowKey.compareTo(new RowKeyWrapper(null)));
  assertEquals(0, rowKey.compareTo(new RowKeyWrapper(ByteString.copyFromUtf8("a"))));
  assertEquals(1, new RowKeyWrapper(null).compareTo(rowKey));
  RowKeyWrapper anotherRowKey = new RowKeyWrapper(ByteString.copyFromUtf8("b"));
  assertEquals("a".compareTo("b"), rowKey.compareTo(anotherRowKey));
  assertEquals("b".compareTo("a"), anotherRowKey.compareTo(rowKey));
}