Eclipse - An open-source, platform-independent software framework.

Eclipse is an open source community whose projects are focused on building an 
open development platform comprised of extensible frameworks, tools, and 
runtimes for building, deploying, and managing software across the lifecycle.

The classic Eclipse package contains: the Eclipse Platform, Java Development 
Tools, and Plug-in Development Environment, including source and both user 
and programmer documentation. 

If you get an error when trying to start eclipse (from the command line) or 
trying to use its internal web browser (which depends on xulrunner), please 
check these threads:
  http://lists.slackbuilds.org/pipermail/slackbuilds-users/2010-June/005979.html
  http://www.mail-archive.com/slackbuilds-users@slackbuilds.org/msg03436.html