You are tired of command-line tools but not ready for an IDE.
Use a color-highlighting editor.
And speaking of Emacs, since it is so extensible, it's natural that people have built enhanced Java capabilities for it. One example is JDEE (Java Development Environment for Emacs), an Emacs "major mode" (jde-mode, based on c-mode) with a set of menu items such as Generate Getters/Setters. You could say that JDEE is in between using a Color-Highlighting Editor and an IDE. The URL for JDEE is http://jdee.sunsite.dk/.
Even without JDEE, Emacs features dabbrev-expand, which does class and method name completion. It is, however, based on what's in your current edit buffers, so it doesn't know about classes in the standard API or in external Jars. For that level of functionality, you have to turn to a full-blown IDE, such as those discussed in Recipe 1.3.