udf.initialize(arguments);
DeferredObject valueObj1 = new DeferredJavaObject(new DateWritable(new Date(109, 06, 20)));
DeferredObject valueObj2 = new DeferredJavaObject(new Integer("4"));
DeferredObject[] args = {valueObj1, valueObj2};
Text output = (Text) udf.evaluate(args);
assertEquals("date_sub() test for DATEWRITABLE failed ", "2009-07-16", output.toString());
// Test with null args
args = new DeferredObject[] { new DeferredJavaObject(null), valueObj2 };