Dave Astels, Test-Driven Development: A Practical Guide (Prentice Hall PTR, 2003). This is the first TDD-related book we have seen that uses a Swing application as its central example, rather than yet another web application. This is an excellent tour through all the basics of TDD, some JUnit-related tools, Mock Objects, and a fully developed example, test by test.
Johannes Link, Unit Tests with Java: How the Tests Drive the Code (Morgan Kauf-mann, 2003). This is another fine look at test-driven development using JUnit.
Vincent Massol and Ted Husted, JUnit in Action (Manning, 2004). This is a tutorial approach to JUnit with advice on testing a wide range of Java applications and components.
Andrew Hunt ...