Generic version of swing classes.

Adapted from

  commit 46ef5b488a
  Author: Paul Phillips <paulp@improving.org>
  Date:   3 years ago

      scala trunk modified to build with java 7.

      At this time a common source base is not possible due to java7
      "generifying" some swing classes, such that they exist with no type
      parameter in java6 but with one in java7.