Hello feniger
Try looking in the program's menus for a "step in" or "step over" command and remember its shortcut key. If you use "step in" the debugger will run into each method it encounters, while "step over" will run the method and continue to the next line of code. Most IDEs have this functionality. You must be in debug mode though.
It is also useful to use break points in your program. The program will execute normally while you are in debug mode and when it encounters a break point, it will stop and then you can take a look at your variables by using adding watch.
I have never used eclipse, but I think it should, at least, have these debugging features available.

If it does not, consider using Netbeans.