3. Thread Group

3. Thread Group
	Chapter 7. Threads

Every Java thread is a member of a thread group.

Default Group: The same as the thread that created it.

Start up Group: the Java runtime system creates a ThreadGroup named "main".

The ThreadGroup class manages groups of threads for Java applications.

Figure 7.2. ThreadGroup Class

The ThreadGroup class has methods that can be categorized as follows:

Collection Management Methods - methods that manage the collection of threads and subgroups contained in the thread group;
Methods that Operate on the Group - these methods set or get attributes of the ThreadGroup object;
Methods that Operate on All Threads within a Group - this is a set of methods that perform some operation on all the threads and subgroups within the ThreadGroup;
resume();
stop();
suspend():
Access Restriction Methods - ThreadGroup and Thread allow the security manager to restrict access to threads based on group membership.


2. Thread Attributes		4. Synchronizing Threads