I believe that the OP is asking for the equivalent to NetBean's "show javadoc" command, where in the IDE, you can just right-click on a library, and it will fire up your browser with the applicable section displayed. Its very nice.
David Newton wrote:Oh. Shift-F2 does that on a referenced library in the package explorer if the Javadoc location has been specified.
The JavaDoc generator is the "Projects/Generate JavaDoc" menu selection.
As David mentioned, you can do a key sequence to display a known javadoc. However, merely hovering the pointer over the item in question is sufficient to activate the pop-up display. Further instructions on how to use that feature appear within the display window.
An IDE is no substitute for an Intelligent Developer.
Shift-F2 opens up the external Javadocs for the entire library (in the package explorer). Hover in a Java editor shows the docs for item, clicking on it shows the Javadoc for that item in the Javadoc tab/view.