If you want the full JavaDoc in a browser integrated in Eclipse (which is what NetBeans gave us) rather than the part of the JavaDoc relevant to a specific class:
Window > Show View > Other > Internal Web Browser
This gives you a browser embedded in Eclipse.
Then type the URL:
<User Home>/wpilib/java/current/javadoc/index.html
It looks like this. (I haven't updated from the beta to current yet so my URL is a tiny bit different in the screenshot than yours will be.)
