One of the problems with standard class reference documentation such as that produced by javadoc is that it concentrates on what classes are available and what methods they have but omits to tell you how or where you might expect to use them. Although very simplistic in its approach, the output produced by jxref can sometimes be a useful additon to javadoc documentation.
See here for an example of the output of jxref, when applied to the JDK 1.0.2 source files. The following command line was used:
May the source be with you!