Unit Testing Java Concurrent Code

Concurrency has become an increasingly important topic in the Java space. Nevertheless, most Java developers do not address concurrency in their unit tests. This talk shows how to and how not to test concurrent code and introduces Thread Weaver, a library for testing concurrent code.

While software engineers can disagree on almost any concept of programming best-practice, the necessity of writing unit tests remains undisputed. With the advent of concurrent applications and the ongoing deprecation of the one-thread-per-request model, unit tests do however miss an increasing fraction of programming errors such as race conditions or dead-locking code. But is it even possible to write tests that revise such errors? In the end, a good unit test is characterized by a determined execution path what effectively prevents the use of concurrency within a single test. However, there are tools and programming principles that allow for unit tests of concurrent code. This talk reviews typical mistakes made when concurrent code is tested and introduces Thread Weaver, a test suite for writing valid unit tests that uncover concurrency-related programming errors.

Video producer: http://www.javazone.no