Sounds like you want to automate the extraction of infomoation of classss.
I won't give you a step-by-step instruction, but following the tradition
of beg, borrow, steal, then write, there's a guy who's done half of your work.
Ian F Darwin For Java CookBook 2ndEd, Ch25.7.
The idea follows like this.
For the jar file you want to inspect, extract the jar file, by unzipping it.
now we have a bunch of class, so for each class, we use the
java.lsng.Class, and java.lang.reflect
and hack out the infomation.
They allow you to obtain what the class contains, what method thay have,
what parent they are from, and anything else that the Java doc contains,
you will be able to obtain the infomation.
In a nutshell, the javadoc IS made from using these, so there isn't any suprise here.
The good thing about these, is that the code could be made for classes that are not
even existing yet. Also it it good to note, (or ovious from reading the javadoc) that
you can dianmically construct classes, and inveoke methods on the fly, and such if
the desire to do so ever arises.
The reflection class is probably what you will need.
I don't quite follow waat you mean by 'class that you can drag', but
here's my (or Ian's) $0.02 worth of note.
p.s. javadoc is your friend.
cat * | w3m -dump -T text/html |grep does wonders