Eclipse opens .class instead of .java

One neat feature of Eclipse (and other IDEs) is that you can hold CTRL and click on a function or variable to go to its definition.

A problem which may occur in Eclipse is that it opens the .class file (the compiled file) instead of opening the .java file when you do this. This is probably caused by the order of the entries in the .classpath file.

Go to your project directory and open the .classpath file. Move all entires of type classpathentry with attribute kind="src" to the top of the file (or at least above any entries with kind "output").

Restart Eclipse and the problem should be fixed.