@Override
  public String getName() {
    return _name;
  }
@Test
  public void testStringHammingDistanceTransformFunction() {
    ExpressionContext expression = RequestContextUtils.getExpression(
        String.format("hamming_distance(%s, %s)", STRING_ALPHANUM_SV_COLUMN, STRING_ALPHANUM_SV_COLUMN));
    TransformFunction transformFunction = TransformFunctionFactory.get(expression, _dataSourceMap);
    assertTrue(transformFunction instanceof ScalarTransformFunctionWrapper);
    assertEquals(transformFunction.getName(), "hammingDistance");
    int[] expectedValues = new int[NUM_ROWS];
    for (int i = 0; i < NUM_ROWS; i++) {
      int distance = 0;
      for (int j = 0; j < _stringAlphaNumericSVValues[i].length(); j++) {
        if (_stringAlphaNumericSVValues[i].charAt(j) != _stringAlphaNumericSVValues[i].charAt(j)) {
          distance++;
        }
      }
      expectedValues[i] = distance;
    }
    testTransformFunction(transformFunction, expectedValues);
  }