When writing JUnit tests developers often add log statements that can help provide information on test failures. During the initial attempt to find a failure a simple System.out.println() statement is usually the first resort of most developers.
Replacing these System.out.println() statements with log statements is the first improvement on this technique. Using SLF4J (Simple Logging Facade for Java) provides some neat improvements using parameterized messages. Combining SLF4J with JUnit 4 rule implementations can provide more efficient test class logging techniques.