package net.jcip.examples; import java.util.concurrent.*; import java.util.concurrent.atomic.*; import junit.framework.TestCase; /** * TestingThreadFactory *
* Testing thread pool expansion * * @author Brian Goetz and Tim Peierls */ public class TestThreadPool extends TestCase { private final TestingThreadFactory threadFactory = new TestingThreadFactory(); public void testPoolExpansion() throws InterruptedException { int MAX_SIZE = 10; ExecutorService exec = Executors.newFixedThreadPool(MAX_SIZE); for (int i = 0; i < 10 * MAX_SIZE; i++) exec.execute(new Runnable() { public void run() { try { Thread.sleep(Long.MAX_VALUE); } catch (InterruptedException e) { Thread.currentThread().interrupt(); } } }); for (int i = 0; i < 20 && threadFactory.numCreated.get() < MAX_SIZE; i++) Thread.sleep(100); assertEquals(threadFactory.numCreated.get(), MAX_SIZE); exec.shutdownNow(); } } class TestingThreadFactory implements ThreadFactory { public final AtomicInteger numCreated = new AtomicInteger(); private final ThreadFactory factory = Executors.defaultThreadFactory(); public Thread newThread(Runnable r) { numCreated.incrementAndGet(); return factory.newThread(r); } }