@Test
public void testCreateConstraints() {

	try {
		JobVertexID id1 = new JobVertexID();
		JobVertexID id2 = new JobVertexID();
		JobVertex vertex1 = new JobVertex("vertex1", id1);
		vertex1.setParallelism(2);
		
		JobVertex vertex2 = new JobVertex("vertex2", id2);
		vertex2.setParallelism(3);
		
		CoLocationGroup group = new CoLocationGroup(vertex1, vertex2);
		
		AbstractID groupId = group.getId();
		assertNotNull(groupId);
		
		CoLocationConstraint constraint1 = group.getLocationConstraint(0);
		CoLocationConstraint constraint2 = group.getLocationConstraint(1);
		CoLocationConstraint constraint3 = group.getLocationConstraint(2);
		
		assertFalse(constraint1 == constraint2);
		assertFalse(constraint1 == constraint3);
		assertFalse(constraint2 == constraint3);
		
		assertEquals(groupId, constraint1.getGroupId());
		assertEquals(groupId, constraint2.getGroupId());
		assertEquals(groupId, constraint3.getGroupId());
	}
	catch (Exception e) {
		e.printStackTrace();
		fail(e.getMessage());
	}
}