Units Tests and Bag Class (and equals() method)

jbalint · **Posted:** Thu Apr 29, 2004 11:44 pm

If equals() is not implemented on Bag, how should I do a unit test like the following:

Code:

PersistedObject p = new PersistedObject();
p.setSomeProperty("someValue");

session.save(p);

PersistedObject p2 = session.load(p.getId());

assertEquals(p, p2);

It will always fail, even when it should pass.

gavin · **Posted:** Thu Apr 29, 2004 11:50 pm

Your equals() method should certainly not include collection-valued properties. They are not part of the natural key.

jbalint · **Posted:** Fri Apr 30, 2004 12:03 am

How then do you recommend that I ensure that collections were persisted as I need them to be?

emmanuel · **Posted:** Fri Apr 30, 2004 1:29 pm

Eheh, that was the first thing I disagreed with Gavin. Not implementing bag equals properly is inconsistent but efficient.
You may be able to find a patch for that in Jira.

jbalint · **Posted:** Fri Apr 30, 2004 1:32 pm

Thanks, I don't agree or not with implementing equals() on the Bag class. I saw the older thread on this where you two talked about it.

I just need to know what the recommended way is to unit test loading classes that have collections on them? Is using equals() the wrong way? If so, then how should I go about it?

Thanks for your input.

emmanuel · **Posted:** Fri Apr 30, 2004 1:52 pm

Well your unit tests should not test Hibernate (it has its own unit test suite).
But I usually test either a particular proeprty or the natural key. I do not do object equals

rollatwork · **Posted:** Fri May 21, 2004 9:23 pm

Our continuous build server currently spends most of its time executing our Hibernate DAO unit tests. I think most of this time is due to dbunit tearing down and rebuilding the integration db.

Our department has been pretty dogmattic in writing unit tests for our domain and dao layers. It's an interesting comment because I know developers on my team would love to stop writing unit tests for this layer if given the choice.

If I'm playing devil's advocate I'd say that these unit tests have value because we are asserting that returned entities are in fact the ones that a client layer are expecting.

I hope I've been clear. Could you elaborate on your comment Emmanuel?

emmanuel · **Posted:** Sat May 29, 2004 6:32 am

Actually I do unit test my DAO because my Hibernate usage logic may be broken.
But I do not test the Hibernate capability of loading a collection.

To increase my early devs, I start with HSQLDB and SchemaExport. That's really cool, no need of DB instance, memory DB, no network usage etc... But sooner or later you have to switch to your real DB