In the previous chapter, we learned how to write and run unit tests for Java applications using Eclipse and JUnit. In this chapter, we are going to learn how to use Eclipse to debug JEE applications. Debugging is an unavoidable part of application development. Unless the application is very simple, the chances are that it is not going to work as expected on the very first attempt and you will spend some time trying to find out the reasons why. In very complex applications, application developers may end up spending more time debugging than writing application code. Problems may not necessarily exist in your code, but may exist in the external system that your application depends on. Debugging a complex piece of software requires skill, which can be developed with experience. However, it also needs good support from the application runtime and IDE.
There are different ways to debug an application. You may just put System.out.println() statements in...