@Test
public void testSingleFieldExtraction() throws InstantiationException, IllegalAccessException {

	// extract single fields
	for (int i = 0; i < Tuple.MAX_ARITY; i++) {
		Tuple current = (Tuple) CLASSES[i].newInstance();
		for (int j = 0; j < i; j++) {
			current.setField(testStrings[j], j);
		}
		for (int j = 0; j < i; j++) {
			assertEquals(testStrings[j], new FieldFromTuple<String>(j).extract(current));
		}
	}
}