Just Java™ 2

Thread Groups

A Thread group is (big surprise!) a group of Threads. A Thread group can contain a set of Threads as well as a set of other Thread groups. It's a way of bundling several related threads together and doing certain housekeeping things to all of them, like starting them all with a single method invocation.

There are methods to create a Thread group and add a Thread to it. You can get a reference to your Thread group for later use:

private ThreadGroup mygroup;mygroup=Thread.currentThread().getThreadGroup();

Thread groups exist because it turned out to be a useful concept in the runtime library. There seemed no reason not to just pass it through to application programmers, as well. The designers of the new java.util.concurrency ...