| /* |
| * Copyright (c) 2012, 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. |
| */ |
| |
| import java.util.concurrent.atomic.AtomicInteger; |
| import java.util.function.Supplier; |
| import org.testng.annotations.Test; |
| import static org.testng.Assert.*; |
| |
| /** |
| * @test |
| * @run testng ThreadLocalSupplierTest |
| * @summary tests ThreadLocal.withInitial(<Supplier>). |
| * Adapted from java.lang.Basic functional test of ThreadLocal |
| * |
| * @author Jim Gish <jim.gish@oracle.com> |
| */ |
| @Test |
| public class ThreadLocalSupplierTest { |
| |
| static final class IntegerSupplier implements Supplier<Integer> { |
| |
| private final AtomicInteger supply = new AtomicInteger(0); |
| |
| @Override |
| public Integer get() { |
| return supply.getAndIncrement(); |
| } |
| |
| public int numCalls() { |
| return supply.intValue(); |
| } |
| } |
| |
| static IntegerSupplier theSupply = new IntegerSupplier(); |
| |
| static final class MyThreadLocal extends ThreadLocal<Integer> { |
| |
| private final ThreadLocal<Integer> delegate; |
| |
| public volatile boolean everCalled; |
| |
| public MyThreadLocal(Supplier<Integer> supplier) { |
| delegate = ThreadLocal.<Integer>withInitial(supplier); |
| } |
| |
| @Override |
| public Integer get() { |
| return delegate.get(); |
| } |
| |
| @Override |
| protected synchronized Integer initialValue() { |
| // this should never be called since we are using the factory instead |
| everCalled = true; |
| return null; |
| } |
| } |
| |
| /** |
| * Our one and only ThreadLocal from which we get thread ids using a |
| * supplier which simply increments a counter on each call of get(). |
| */ |
| static MyThreadLocal threadLocal = new MyThreadLocal(theSupply); |
| |
| public void testMultiThread() throws Exception { |
| final int threadCount = 500; |
| final Thread th[] = new Thread[threadCount]; |
| final boolean visited[] = new boolean[threadCount]; |
| |
| // Create and start the threads |
| for (int i = 0; i < threadCount; i++) { |
| th[i] = new Thread() { |
| @Override |
| public void run() { |
| final int threadId = threadLocal.get(); |
| assertFalse(visited[threadId], "visited[" + threadId + "]=" + visited[threadId]); |
| visited[threadId] = true; |
| // check the get() again |
| final int secondCheckThreadId = threadLocal.get(); |
| assertEquals(secondCheckThreadId, threadId); |
| } |
| }; |
| th[i].start(); |
| } |
| |
| // Wait for the threads to finish |
| for (int i = 0; i < threadCount; i++) { |
| th[i].join(); |
| } |
| |
| assertEquals(theSupply.numCalls(), threadCount); |
| // make sure the provided initialValue() has not been called |
| assertFalse(threadLocal.everCalled); |
| // Check results |
| for (int i = 0; i < threadCount; i++) { |
| assertTrue(visited[i], "visited[" + i + "]=" + visited[i]); |
| } |
| } |
| |
| public void testSimple() { |
| final String expected = "OneWithEverything"; |
| final ThreadLocal<String> threadLocal = ThreadLocal.<String>withInitial(() -> expected); |
| assertEquals(expected, threadLocal.get()); |
| } |
| } |