jdk-24/test/jdk/java/lang/management/ThreadMXBean/AllThreadIds.java
2020-06-08 09:47:21 -07:00

319 lines
11 KiB
Java

/*
* Copyright (c) 2003, 2020, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @bug 4530538
* @key intermittent
* @summary Basic unit test of ThreadMXBean.getAllThreadIds()
* @author Alexei Guibadoulline and Mandy Chung
*
* @run main/othervm AllThreadIds
*/
import java.lang.management.*;
import java.text.MessageFormat;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.Phaser;
import java.util.function.Supplier;
public class AllThreadIds {
/**
* A supplier wrapper for the delayed format printing.
* The supplied value will have to be formatted as <em>$s</em>
* @param <T> The wrapped type
*/
private static final class ArgWrapper<T> {
private final Supplier<T> val;
public ArgWrapper(Supplier<T> val) {
this.val = val;
}
@Override
public String toString() {
T resolved = val.get();
return resolved != null ? resolved.toString() : null;
}
}
static final int DAEMON_THREADS = 20;
static final int USER_THREADS = 5;
static final int ALL_THREADS = DAEMON_THREADS + USER_THREADS;
private static final boolean live[] = new boolean[ALL_THREADS];
private static final Thread allThreads[] = new Thread[ALL_THREADS];
private static final Set<Long> allThreadIds = new HashSet<>();
private static final ThreadMXBean mbean = ManagementFactory.getThreadMXBean();
private static boolean testFailed = false;
private static boolean trace = false;
private static long prevTotalThreadCount = 0;
private static long prevLiveTestThreadCount = 0;
private static int prevPeakThreadCount = 0;
private static final Phaser startupCheck = new Phaser(ALL_THREADS + 1);
private static void printThreadList() {
long[] list = mbean.getAllThreadIds();
for (int i = 1; i <= list.length; i++) {
System.out.println(i + ": Thread id = " + list[i-1]);
}
for (int i = 0; i < ALL_THREADS; i++) {
Thread t = allThreads[i];
System.out.println(t.getName() + " Id = " + t.getId() +
" die = " + live[i] +
" alive = " + t.isAlive());
}
}
private static void checkInitialState() throws Exception {
updateCounters();
checkThreadCount(0, 0);
}
private static void checkAllThreadsAlive() throws Exception {
updateCounters();
// Start all threads and wait to be sure they all are alive
for (int i = 0; i < ALL_THREADS; i++) {
setLive(i, true);
Thread thread = new MyThread(i);
thread.setDaemon(i < DAEMON_THREADS);
thread.start();
allThreadIds.add(thread.getId());
allThreads[i] = thread;
}
// wait until all threads are started.
startupCheck.arriveAndAwaitAdvance();
checkThreadCount(ALL_THREADS, 0);
if (trace) {
printThreadList();
}
// Check mbean now. All threads must appear in getAllThreadIds() list
Set<Long> currentThreadIds = new HashSet<>();
Arrays.stream(mbean.getAllThreadIds()).forEach(currentThreadIds::add);
if (!currentThreadIds.containsAll(allThreadIds)) {
testFailed = true;
if (trace) {
System.out.print(". TEST FAILED.");
}
}
if (trace) {
System.out.println();
}
}
private static void checkDaemonThreadsDead() throws Exception {
updateCounters();
// Stop daemon threads, wait to be sure they all are dead, and check
// that they disappeared from getAllThreadIds() list
for (int i = 0; i < DAEMON_THREADS; i++) {
setLive(i, false);
}
// make sure the daemon threads are completely dead
joinDaemonThreads();
// and check the reported thread count
checkThreadCount(0, DAEMON_THREADS);
// Check mbean now
long[] list = mbean.getAllThreadIds();
for (int i = 0; i < ALL_THREADS; i++) {
long expectedId = allThreads[i].getId();
boolean found = false;
boolean alive = (i >= DAEMON_THREADS);
if (trace) {
System.out.print("Looking for thread with id " + expectedId +
(alive ? " expected alive." : " expected terminated."));
}
for (int j = 0; j < list.length; j++) {
if (expectedId == list[j]) {
found = true;
break;
}
}
if (alive != found) {
testFailed = true;
}
if (trace) {
if (alive != found) {
System.out.println(" TEST FAILED.");
} else {
System.out.println();
}
}
}
}
private static void checkAllThreadsDead() throws Exception {
updateCounters();
// Stop all threads and wait to be sure they all are dead
for (int i = DAEMON_THREADS; i < ALL_THREADS; i++) {
setLive(i, false);
}
// make sure the non-daemon threads are completely dead
joinNonDaemonThreads();
// and check the thread count
checkThreadCount(0, ALL_THREADS - DAEMON_THREADS);
}
private static void checkThreadCount(int numNewThreads,
int numTerminatedThreads) {
checkLiveThreads(numNewThreads, numTerminatedThreads);
checkPeakThreads(numNewThreads);
checkTotalThreads(numNewThreads);
checkThreadIds(numNewThreads, numTerminatedThreads);
}
private static void checkLiveThreads(int numNewThreads,
int numTerminatedThreads) {
int diff = numNewThreads - numTerminatedThreads;
long threadCount = mbean.getThreadCount();
long expectedThreadCount = prevLiveTestThreadCount + diff;
// Check that number of live test threads is no less
// than number of all threads returned by mbean.getThreadCount()
if (threadCount < expectedThreadCount) {
testFailed = true;
System.err.println(MessageFormat.format("Unexpected number of threads count %d." +
"The expected number is %d or greater", threadCount, expectedThreadCount));
}
}
private static void checkPeakThreads(int numNewThreads) {
long peakThreadCount = mbean.getPeakThreadCount();
long expectedThreadCount = Math.max(prevPeakThreadCount, numNewThreads);
if (peakThreadCount < expectedThreadCount) {
testFailed = true;
System.err.println(MessageFormat.format("Unexpected number of peak threads count %d." +
"The expected number is %d or greater", peakThreadCount, expectedThreadCount));
}
}
private static void checkTotalThreads(int numNewThreads) {
long totalThreadCount = mbean.getTotalStartedThreadCount();
long expectedThreadCount = prevTotalThreadCount + numNewThreads;
if (totalThreadCount < expectedThreadCount) {
testFailed = true;
System.err.println(MessageFormat.format("Unexpected number of total threads %d." +
"The expected number is %d or greater", totalThreadCount, expectedThreadCount));
}
}
private static void checkThreadIds(int numNewThreads, int numTerminatedThreads) {
int threadCount = mbean.getAllThreadIds().length;
int expectedThreadCount = numNewThreads - numTerminatedThreads;
if (threadCount < expectedThreadCount) {
testFailed = true;
System.err.println(MessageFormat.format("Unexpected number of threads %d." +
"The expected number is %d or greater", threadCount, expectedThreadCount));
}
}
private static long getTestThreadCount() {
return Thread.getAllStackTraces().keySet().stream().filter(
thread -> thread.isAlive() && allThreadIds.contains(thread.getId())).count();
}
private static void updateCounters() {
prevTotalThreadCount = mbean.getTotalStartedThreadCount();
prevLiveTestThreadCount = getTestThreadCount();
prevPeakThreadCount = mbean.getPeakThreadCount();
}
public static void main(String args[]) throws Exception {
if (args.length > 0 && args[0].equals("trace")) {
trace = true;
}
checkInitialState();
checkAllThreadsAlive();
checkDaemonThreadsDead();
checkAllThreadsDead();
if (testFailed)
throw new RuntimeException("TEST FAILED.");
System.out.println("Test passed.");
}
private static void joinDaemonThreads() throws InterruptedException {
for (int i = 0; i < DAEMON_THREADS; i++) {
allThreads[i].join();
}
}
private static void joinNonDaemonThreads() throws InterruptedException {
for (int i = DAEMON_THREADS; i < ALL_THREADS; i++) {
allThreads[i].join();
}
}
private static void setLive(int i, boolean val) {
synchronized(live) {
live[i] = val;
}
}
private static boolean isLive(int i) {
synchronized(live) {
return live[i];
}
}
// The MyThread thread lives as long as correspondent live[i] value is true
private static class MyThread extends Thread {
int id;
MyThread(int id) {
this.id = id;
}
public void run() {
// signal started
startupCheck.arrive();
while (isLive(id)) {
try {
sleep(100);
} catch (InterruptedException e) {
System.out.println("Unexpected exception is thrown.");
e.printStackTrace(System.out);
testFailed = true;
}
}
}
}
}