Thread Groups
When a number of threads are to be handled in the same manner, they can be put in a thread group.
ThreadGroup tg = new ThreadGroup("my sprites");
There’s a Thread constructor that takes a group as an arg.
public Thread(ThreadGroup g,
Runnable target, String name);
There are many methods for ThreadGroup objects such as getMaxPriority, destroy, etc.
ThreadGroups can contain ThreadGroups. Trees of ThreadGroups are therefore possible.