Understand Eclipse classes by class diagram

Nowadays I working more and more with Eclipse, especially I'm writing some plug-ins to make it suit my needs, and I'm finding hard to understand all the relationships and dependencies that exists between all Eclipse's packages I am using.

One (hard) way is to dig into Eclipse help, but it's hard to believe that you will get somewhere very soon. Another (easy/convenient) way I found to be the usage of a Java class generator that is hosted online and which knows already over 70000 classes from different open-source Java well-known packages, such as Eclipse, Android, Open JDK, Squirrel SQL, JBoss, etc.

So here I am, looking up for some IDocumentSetupParticipant interface and not knowing what else in Eclipse it's using this. But there is a easy/convenient way to work out this, right?

The tool I'm talking about is AgileJ StructureView and if it's happening that you need to get the big picture of a class within those open-source packages that I have already mentioned earlier, then you can just point your browser at ttp://www.agilej.com then search for your open-source project and click that link that will give you a page where you can search for a package or class name, member, whatever. It will present you the found class and its relationships (dependency/inheritance) with other classes.

It really has helped me understand Eclipse class diagram with easy.

Smooth and nice...