@Test(expected=IllegalArgumentException.class)
public void testDeleteNullAssignment()
{
System.out.println("deleteNullAssignment");
assertTrue(instance.isOpen());
GradedEvent gradedEvent = new GradedEvent();
CourseDAO courseDAO = new CourseDAO(testDb.getConnection());
Course course = courseDAO.find(1L);
gradedEvent.setCourse(course);
gradedEvent.setTerm("Summer 2010");
gradedEvent.setVersion("M2");
gradedEvent.setId(new Long(3L));
courseDAO.closeConnection();
instance.delete(gradedEvent);
}