code: private AssertionError createComparisonFailure(String className, String expected, String actual) throws Exception {
  		Class<?> clazz = Class.forName(className);
  		Constructor<?> constructor = clazz.getConstructor(String.class, String.class, String.class);
  		return (AssertionError) constructor.newInstance("", expected, actual);
  	}
docs: Attempts to create an instance of junit's ComparisonFailure exception using reflection.