@Test(expectedExceptions = SpecException.class)
  public void testSpecExceptions() throws IOException {
    String testPath = "/json/cardinality/failCardinalityType";
    Map<String, Object> testUnit = JsonUtils.classpathToMap(testPath + ".json");

    Object spec = testUnit.get("spec");

    // Should throw exception
    new CardinalityTransform(spec);
  }
  @Test(dataProvider = "getTestCaseUnits")
  public void runTestUnits(String testCaseName) throws IOException {

    String testPath = "/json/cardinality/" + testCaseName;
    Map<String, Object> testUnit = JsonUtils.classpathToMap(testPath + ".json");

    Object input = testUnit.get("input");
    Object spec = testUnit.get("spec");
    Object expected = testUnit.get("expected");

    CardinalityTransform cardinalityTransform = new CardinalityTransform(spec);
    Object actual = cardinalityTransform.transform(input);

    JoltTestUtil.runDiffy("failed case " + testPath, expected, actual);
  }