Java 自訂 線程池與任務隊列

說明：
1）使用了隊列的先進先出思想
2）在執行的時候添加線程
3）在ThreadQueue 裡實現從隊列裡取出線程

/** *  * @Project    JavaDemos * @Package    com.java.thread * @author     chenlin * @version    1.0 * @Date       2011年6月12日 */public class WorkQueue {    private int threadCounts;// 線程池的大小    private ThreadQueue[] threads;// 用數組實現線程池    private LinkedList queue;// 任務隊列    public WorkQueue(int threadCounts) {        this.threadCounts = threadCounts;        this.threads = new ThreadQueue[threadCounts];        this.queue = new LinkedList();        for (int i = 0; i < threadCounts; i++) {            threads[i] = new ThreadQueue();            threads[i].start();// 啟動所有背景工作執行緒        }    }    public void execute(Runnable r) {        synchronized (queue) {            queue.addLast(r);            queue.notify();        }    }    private class ThreadQueue extends Thread {// 背景工作執行緒類        @Override        public void run() {            Runnable r;            while (true) {                synchronized (queue) {                    //                    while (queue.isEmpty()) {                        try {                            queue.wait();                        } catch (InterruptedException e) {                            e.printStackTrace();                        }                    }                    r = (Runnable) queue.removeFirst();// 有任務時，取出任務                }                r.run();            }        }    }    /**     * 在靜態方法裡調用內部類必須是靜態     */    static class Mytask implements Runnable {// 任務介面        public void run() {            String name = Thread.currentThread().getName();            try {                Thread.sleep(100);// 類比任務執行的時間            } catch (InterruptedException e) {            }            System.out.println(name + " executed OK");        }    }    public static void main(String[] args) {        WorkQueue wq = new WorkQueue(10);// 10個背景工作執行緒          Mytask r[] = new Mytask[20];// 20個任務          for (int i = 0; i < 20; i++) {              r[i] = new Mytask();              wq.execute(r[i]);          }      }}

運行結果：
Thread-2 executed OK
Thread-6 executed OK
Thread-1 executed OK
Thread-5 executed OK
Thread-9 executed OK
Thread-7 executed OK
Thread-4 executed OK
Thread-8 executed OK
Thread-3 executed OK
Thread-0 executed OK
Thread-2 executed OK
Thread-5 executed OK
Thread-1 executed OK
Thread-9 executed OK
Thread-7 executed OK
Thread-6 executed OK
Thread-4 executed OK
Thread-8 executed OK
Thread-3 executed OK
Thread-0 executed OK