Integration testing transactions and optimistic locking with Spring and JUnit

Posted on by

I did some badness today.

I wanted an integration test to check to see if my @Transactional method actually did rollback on an optimistic lock failure. It’s a pretty business critical method so I wanted to be sure that the whole @Transactional and @Version annotation voodoo actually works.

The approach I took was to inject, what I called a “slowRepository” into the object with the @Transactional method. The slowRepository is just a mockito mock of the object which “answers” (using “thenAnswer”) to the “findBy…” with some custom code.

The idea is that at some point during the @Transactional method the slowRepository is called and the “answer” code is invoked. In the test, the answer code follows along the lines of:

1. Grab the data it requires from the (not slow) repository (the repository the slowRepository is mocking)
2. Switch back the slowRepository for the not slow repository
3. Invoke the @Transactional method again on a separate thread
4. Sleep for a bit
5. Wake up and return the data from step 1

The @Transactional call on the separate thread completes and commits before slowRepository wakes up. When it does, slowRepository returns stale data and the @Transactional method then fails accordingly.

The problem I encountered was using the setters for my @Autowired dependencies on the bean with the @Transactional method. I needed to use the setters so that I could switch in and out the slowRepository, but couldn’t because Spring AOP proxies are implementations of an interface, not subclasses (by default – yes I realise you can get Spring to proxy the target class using CGLIB). I found this blog post which explains how to get at the target object behind a Spring proxy. I converted it to Scala:

…which is pretty ninja.

11,575 thoughts on “Integration testing transactions and optimistic locking with Spring and JUnit”

  1. Its like you read my mind You appear to know a lot about this like you wrote the book in it or something. I think that you could do with some pics to drive the message home a little bit but other than that this is magnificent blog. A fantastic read. Ill certainly be back. https://share.google/HPGVH1ncbqDn48GrA

  13. Great beat ! I would like to apprentice even as you amend your site, how can i subscribe for a weblog site?
    The account aided me a appropriate deal. I had been tiny bit acquainted of this
    your broadcast provided brilliant transparent
    concept

  25. Бытовка из сэндвич-панелей с металлическим каркасом — прочность проверена. Поставили кран-балку внутри для перемещения тяжёлых деталей. Конструкция выдержала нагрузку без проблем. бытовка каркасник Москва

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>