I recently came across a great example of JavaDoc. It was regarding the AssertJ SoftAssertions class.
It's in the references1.
In short, we have a dinner party hosted at a mansion.
And we're going to use a UnitTest with Assertions to determine if one of the guests has been murdered and who dun it.
It made me smile.
I don't really like Softly Asserts, and I notice that a lot of developers at work seem to use it all the time.
And since it's Christmas today (Merry Christmas!), let's get into the spirit of the season by testing if there is a Miracle on 34th Street.
We are going to use SoftlyAssertions with the following test written below:
And it looks fine if the tests run properly.
But when the tests fail, likely as not we see NullPointerExceptions instead of useful asserts.
Let's try to fail the test, by removing the town.
And lo and behold, we get this:
I really would like for SoftAssertions to only be used during checking of simple properties within an object, thanks!
And not this cross-boundary stuff.
I was talking with a colleague on the way home, when we started talking about his troubles with his bike.
In short, he could turn the pedals like crazy, and the bike was not moving an inch.
That's when I realized that this is a perfect example of the difference between Unit Testing and Integration Testing.
In short:
write a unit test, to see if we can properly turn the pedals in the proper direction.
Conclusion: Success! Software works fine. In fact it works extremely well. We achieved a performance increase of over 500%! Yay!
write an integration test, to see if when we turn the pedals, the bicycle will move.
Conclusion: Failure! Pedals turn fine, but the bicycle doesn't move.
It turns out the integration between the component "pedals" and the component "wheels" was busted.
It totally shows that though Unit tests may all pass, it is not a guarantee that your software is actually doing what it should.
Lesson learned.
I recently was wondering if it was possible and a good idea to test resource bundles in Unit Tests.
Most likely it is not, but in our case we were checking the layout of log messages. To see if the messages lined up properly.
It only works if the properties file is available in the resources of the project. (in our case the properties files are all in an unrelated project (parent project), so it was either moving the unit test to a bad place, or moving the property files.)
