package concurrent; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; public class TestThreadPool { public static void main(String args[]) throws InterruptedException { // only two threads ExecutorService exec = Executors.newFixedThreadPool(2); for(int index = 0; index < 100; index++) { Runnable run = new Runnable() { public void run() { long time = (long) (Math.random() * 1000); System.out.println(“Sleeping ” + time + “ms”); try { Thread.sleep(time); } catch (InterruptedException e) { } } }; exec.execute(run); } // must shutdown exec.shutdown(); } }//源代码片段来自云代码http://yuncode.net package concurrent; import static java.util.concurrent.TimeUnit.SECONDS; import java.util.Date; import java.util.concurrent.Executors; import java.util.concurrent.ScheduledExecutorService; import java.util.concurrent.ScheduledFuture; public class TestScheduledThread { public static void main(String[] args) { final ScheduledExecutorService scheduler = Executors .newScheduledThreadPool(2); final Runnable beeper = new Runnable() { int count = 0; public void run() { System.out.println(new Date() + ” beep ” + (++count)); } }; // 1秒钟后运行,并每隔2秒运行一次 final ScheduledFuture beeperHandle = scheduler.scheduleAtFixedRate( beeper, 1, 2, SECONDS); // 2秒钟后运行,并每次在上次任务运行完后等待5秒后重新运行 final ScheduledFuture beeperHandle2 = scheduler .scheduleWithFixedDelay(beeper, 2, 5, SECONDS); // 30秒后结束关闭任务,并且关闭Scheduler scheduler.schedule(new Runnable() { public void run() { beeperHandle.cancel(true); beeperHandle2.cancel(true); scheduler.shutdown(); } }, 30, SECONDS); } }//源代码片段来自云代码http://yuncode.net package concurrent; import java.text.SimpleDateFormat; import java.util.Date; import java.util.concurrent.BrokenBarrierException; import java.util.concurrent.CyclicBarrier; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; public class TestCyclicBarrier { // 徒步需要的时间: Shenzhen, Guangzhou, Shaoguan, Changsha, Wuhan private static int[] timeWalk = { 5, 8, 15, 15, 10 }; // 自驾游 private static int[] timeSelf = { 1, 3, 4, 4, 5 }; // 旅游大巴 private static int[] timeBus = { 2, 4, 6, 6, 7 }; static String now() { SimpleDateFormat sdf = new SimpleDateFormat(“HH:mm:ss”); return sdf.format(new Date()) + “: “; } static class Tour implements Runnable { private int[] times; private CyclicBarrier barrier; private String tourName; public Tour(CyclicBarrier barrier, String tourName, int[] times) { this.times = times; this.tourName = tourName; this.barrier = barrier; } public void run() { try { Thread.sleep(times[0] * 1000); System.out.println(now() + tourName + ” Reached Shenzhen”); barrier.await(); Thread.sleep(times[1] * 1000); System.out.println(now() + tourName + ” Reached Guangzhou”); barrier.await(); Thread.sleep(times[2] * 1000); System.out.println(now() + tourName + ” Reached Shaoguan”); barrier.await(); Thread.sleep(times[3] * 1000); System.out.println(now() + tourName + ” Reached Changsha”); barrier.await(); Thread.sleep(times[4] * 1000); System.out.println(now() + tourName + ” Reached Wuhan”); barrier.await(); } catch (InterruptedException e) { } catch (BrokenBarrierException e) { } } } public static void main(String[] args) { // 三个旅行团 CyclicBarrier barrier = new CyclicBarrier(3); ExecutorService exec = Executors.newFixedThreadPool(3); exec.submit(new Tour(barrier, “WalkTour”, timeWalk)); exec.submit(new Tour(barrier, “SelfTour”, timeSelf)); exec.submit(new Tour(barrier, “BusTour”, timeBus)); exec.shutdown(); } }//源代码片段来自云代码http://yuncode.net package concurrent; import java.io.File; import java.io.FileFilter; import java.util.concurrent.BlockingQueue; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.LinkedBlockingQueue; import java.util.concurrent.atomic.AtomicInteger; public class TestBlockingQueue { static long randomTime() { return (long) (Math.random() * 1000); } public static void main(String[] args) { // 能容纳100个文件 final BlockingQueue queue = new LinkedBlockingQueue(100); // 线程池 final ExecutorService exec = Executors.newFixedThreadPool(5); final File root = new File(“F:\\JavaLib”); // 完成标志 final File exitFile = new File(“”); // 读个数 final AtomicInteger rc = new AtomicInteger(); // 写个数 final AtomicInteger wc = new AtomicInteger(); // 读线程 Runnable read = new Runnable() { public void run() { scanFile(root); scanFile(exitFile); } public void scanFile(File file) { if (file.isDirectory()) { File[] files = file.listFiles(new FileFilter() { public boolean accept(File pathname) { return pathname.isDirectory() || pathname.getPath().endsWith(“.java”); } }); for (File one : files) scanFile(one); } else { try { int index = rc.incrementAndGet(); System.out.println(“Read0: ” + index + ” “ + file.getPath()); queue.put(file); } catch (InterruptedException e) { } } } }; exec.submit(read); // 四个写线程 for (int index = 0; index < 4; index++) { // write thread final int NO = index; Runnable write = new Runnable() { String threadName = “Write” + NO; public void run() { while (true) { try { Thread.sleep(randomTime()); int index = wc.incrementAndGet(); File file = queue.take(); // 队列已经无对象 if (file == exitFile) { // 再次添加”标志”,以让其他线程正常退出 queue.put(exitFile); break; } System.out.println(threadName + “: ” + index + ” “ + file.getPath()); } catch (InterruptedException e) { } } } }; exec.submit(write); } exec.shutdown(); } }//源代码片段来自云代码http://yuncode.net package concurrent; import java.util.concurrent.CountDownLatch; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; public class TestCountDownLatch { public static void main(String[] args) throws InterruptedException { // 开始的倒数锁 final CountDownLatch begin = new CountDownLatch(1); // 结束的倒数锁 final CountDownLatch end = new CountDownLatch(10); // 十名选手 final ExecutorService exec = Executors.newFixedThreadPool(10); for(int index = 0; index < 10; index++) { final int NO = index + 1; Runnable run = new Runnable(){ public void run() { try { begin.await(); Thread.sleep((long) (Math.random() * 10000)); System.out.println(“No.” + NO + ” arrived”); } catch (InterruptedException e) { } finally { end.countDown(); } } }; exec.submit(run); } System.out.println(“Game Start”); begin.countDown(); end.await(); System.out.println(“Game Over”); exec.shutdown(); } }//源代码片段来自云代码http://yuncode.net package concurrent; import java.util.concurrent.Callable; import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; public class TestFutureTask { public static void main(String[] args)throws InterruptedException, ExecutionException { final ExecutorService exec = Executors.newFixedThreadPool(5); Callable call = new Callable() { public String call() throws Exception { Thread.sleep(1000 * 5); return “Other less important but longtime things.”; } }; Future task = exec.submit(call); // 重要的事情 Thread.sleep(1000 * 3); System.out.println(“Let’s do important things.”); // 其他不重要的事情 String obj = task.get(); System.out.println(obj); // 关闭线程池 exec.shutdown(); } }//源代码片段来自云代码http://yuncode.net package concurrent; import java.util.concurrent.Callable; import java.util.concurrent.CompletionService; import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorCompletionService; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; public class TestCompletionService { public static void main(String[] args) throws InterruptedException, ExecutionException { ExecutorService exec = Executors.newFixedThreadPool(10); CompletionService serv = new ExecutorCompletionService(exec); for (int index = 0; index < 5; index++) { final int NO = index; Callable downImg = new Callable() { public String call() throws Exception { Thread.sleep((long) (Math.random() * 10000)); return “Downloaded Image ” + NO; } }; serv.submit(downImg); } Thread.sleep(1000 * 2); System.out.println(“Show web content”); for (int index = 0; index < 5; index++) { Future task = serv.take(); String img = task.get(); System.out.println(img); } System.out.println(“End”); // 关闭线程池 exec.shutdown(); } }//源代码片段来自云代码http://yuncode.net package concurrent; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Semaphore; public class TestSemaphore { public static void main(String[] args) { // 线程池 ExecutorService exec = Executors.newCachedThreadPool(); // 只能5个线程同时访问 final Semaphore semp = new Semaphore(5); // 模拟20个客户端访问 for (int index = 0; index < 20; index++) { final int NO = index; Runnable run = new Runnable() { public void run() { try { // 获取许可 semp.acquire(); System.out.println(“Accessing: ” + NO); Thread.sleep((long) (Math.random() * 10000)); // 访问完后,释放 semp.release(); } catch (InterruptedException e) { } } }; exec.execute(run); } // 退出线程池 exec.shutdown(); } }//源代码片段来自云代码http://yuncode.net