Issue #4121 - Tests for ThreadFactory support in QTP

Signed-off-by: Joakim Erdfelt <joakim.erdfelt@gmail.com>

jetty-util/src/test/java/org/eclipse/jetty/util/thread/ThreadFactoryTest.java

@@ -0,0 +1,104 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2019 Mort Bay Consulting Pty. Ltd.
+//  ------------------------------------------------------------------------
+//  All rights reserved. This program and the accompanying materials
+//  are made available under the terms of the Eclipse Public License v1.0
+//  and Apache License v2.0 which accompanies this distribution.
+//
+//      The Eclipse Public License is available at
+//      http://www.eclipse.org/legal/epl-v10.html
+//
+//      The Apache License v2.0 is available at
+//      http://www.opensource.org/licenses/apache2.0.php
+//
+//  You may elect to redistribute this code under either of these licenses.
+//  ========================================================================
+//
+
+package org.eclipse.jetty.util.thread;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.ThreadLocalRandom;
+import java.util.concurrent.TimeUnit;
+
+import org.eclipse.jetty.util.MultiException;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class ThreadFactoryTest
+{
+    @Test
+    public void testThreadFactory() throws Exception
+    {
+        ThreadGroup threadGroup = new ThreadGroup("my-group");
+        MyThreadFactory threadFactory = new MyThreadFactory(threadGroup);
+
+        QueuedThreadPool qtp = new QueuedThreadPool(200, 10, 2000, 0, null, threadGroup, threadFactory);
+        try
+        {
+            qtp.start();
+
+            int testThreads = 2000;
+            CountDownLatch threadsLatch = new CountDownLatch(testThreads);
+            MultiException mex = new MultiException();
+
+            for (int i = 0; i < testThreads; i++)
+            {
+                qtp.execute(() ->
+                {
+                    try
+                    {
+                        TimeUnit.MILLISECONDS.sleep(ThreadLocalRandom.current().nextInt(20, 500));
+                        Thread thread = Thread.currentThread();
+
+                        if (!thread.getName().startsWith("My-"))
+                        {
+                            mex.add(new AssertionError("Thread " + thread.getName() + " does not start with 'My-'"));
+                        }
+
+                        if (!thread.getThreadGroup().getName().equalsIgnoreCase("my-group"))
+                        {
+                            mex.add(new AssertionError("Thread Group " + thread.getThreadGroup().getName() + " is not 'my-group'"));
+                        }
+
+                        threadsLatch.countDown();
+                    }
+                    catch (InterruptedException e)
+                    {
+                        e.printStackTrace();
+                    }
+                });
+            }
+
+            assertTrue(threadsLatch.await(5, TimeUnit.SECONDS), "Did not see all tasks finish");
+            mex.ifExceptionThrow();
+        }
+        finally
+        {
+            qtp.stop();
+        }
+    }
+
+    public static class MyThreadFactory implements ThreadFactory
+    {
+        private final ThreadGroup threadGroup;
+
+        public MyThreadFactory(ThreadGroup threadGroup)
+        {
+            this.threadGroup = threadGroup;
+        }
+
+        @Override
+        public Thread newThread(Runnable runnable)
+        {
+            Thread thread = new Thread(threadGroup, runnable);
+            thread.setDaemon(false);
+            thread.setPriority(Thread.MIN_PRIORITY);
+            thread.setName("My-" + thread.getId());
+            return thread;
+        }
+    }
+}