com.yahoo.concurrent.Threads Maven / Gradle / Ivy
// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package com.yahoo.concurrent;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
/**
* @author bjorncs
*/
public class Threads {
private Threads() {}
/** Returns all threads in JVM */
public static Collection getAllThreads() {
ThreadGroup root = Thread.currentThread().getThreadGroup();
ThreadGroup parent;
while ((parent = root.getParent()) != null) {
root = parent;
}
// The number of threads may increase between activeCount() and enumerate()
Thread[] threads = new Thread[root.activeCount() + 100];
int count;
while ((count = root.enumerate(threads, true)) == threads.length) {
threads = new Thread[threads.length + 1000];
}
return List.of(Arrays.copyOf(threads, count));
}
}