Whenever I use the Step Into feature (F5) in Eclipse’s debugger, I’m mainly interested in stepping through code in my own classes, not the ones from external libraries or even Java classes.
For example, there’s almost no reason to ever want to step into Spring’s code or proxy classes (other than to learn more about them or maybe debug a potential bug in Spring). And normally I’m not interested in Java util classes (eg. ArrayList). This also goes for Hibernate, Apache Commons, Google and many other external libraries.
Fortunately, Eclipse makes it easy to specify which classes to skip by allowing step filters. This makes it easier to focus on your own code and also keeps your editor area clean since Eclipse won’t be opening classes in separate editors all the time.