Listing All Running Threads
A thread exists in a thread group and a thread group can contain other
thread groups. This example visits all threads in all thread groups.
Here's an example of some thread groups that contain some threads:
// Find the root thread group
ThreadGroup root = Thread.currentThread().getThreadGroup().getParent();
while (root.getParent() != null) {
root = root.getParent();
}
// Visit each thread group
visit(root, 0);
// This method recursively visits all thread groups under `group'.
public static void visit(ThreadGroup group, int level) {
// Get threads in `group'
int numThreads = group.activeCount();
Thread[] threads = new Thread[numThreads*2];
numThreads = group.enumerate(threads, false);
// Enumerate each thread in `group'
for (int i=0; i<numThreads; i++) {
// Get thread
Thread thread = threads[i];
}
// Get thread subgroups of `group'
int numGroups = group.activeGroupCount();
ThreadGroup[] groups = new ThreadGroup[numGroups*2];
numGroups = group.enumerate(groups, false);
// Recursively visit each subgroup
for (int i=0; i<numGroups; i++) {
visit(groups[i], level+1);
}
}
java.lang.ThreadGroup[name=system,maxpri=10]
Thread[Reference Handler,10,system]
Thread[Finalizer,8,system]
Thread[Signal Dispatcher,10,system]
Thread[CompileThread0,10,system]
java.lang.ThreadGroup[name=main,maxpri=10]
Thread[main,5,main]
Thread[Thread-1,5,main]
was much useful