import java.util.concurrent.atomic.AtomicInteger;
import org.apache.log4j.Logger; /** * jdk1.5线程池的简单实现，可以控制任务队列的大小，也可以查看队列的剩余任务数等情况 * */ public class SimpleThreadPool extends ThreadPoolExecutor { private Logger log = Logger.getLogger( getClass());private AtomicInteger taskBalance = new AtomicInteger(0);private int queueCapacity = 100;/*** 构造线程池* @param corePoolSize 核心线程数* @param maximumPoolSize 最大线程数* @param keepAliveTime 非核心线程空闲时间* @param unit 非核心线程空闲时间单位* @param workQueue 任务队列*/public SimpleThreadPool(int corePoolSize, int maximumPoolSize, long keepAliveTime, TimeUnit unit, BlockingQueue<Runnable> workQueue) { super(corePoolSize, maximumPoolSize, keepAliveTime, unit, workQueue);}/*** 构造线程池* @param corePoolSize 核心线程数* @param maximumPoolSize 最大线程数* @param keepAliveSecond 非核心线程空闲时间（单位：秒）* @param workQueue 任务队列*/public SimpleThreadPool(int corePoolSize, int maximumPoolSize, long keepAliveSecond, BlockingQueue<Runnable> workQueue ) { super(corePoolSize, maximumPoolSize, keepAliveSecond, TimeUnit.SECONDS, workQueue );}/*** 构造线程池* @param corePoolSize 核心线程数* @param maximumPoolSize 最大线程数* @param keepAliveSecond 非核心线程空闲时间（单位：秒）*/public SimpleThreadPool(int corePoolSize, int maximumPoolSize, long keepAliveSecond ) { super(corePoolSize, maximumPoolSize, keepAliveSecond, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>() );}/*** 构造单线程的线程池* @param workQueue 任务队列*/public SimpleThreadPool(BlockingQueue<Runnable> workQueue ) { super(1, 1, 1, TimeUnit.SECONDS, workQueue );}/*** 构造单线程的线程池*/public SimpleThreadPool() { super(1, 1, 1, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>() );}/*** 构造单线程的线程池*/public static SimpleThreadPool createSingleThread() { return new SimpleThreadPool();}protected void afterExecute(Runnable r, Throwable t) { super.afterExecute(r, t);taskBalance.decrementAndGet();if( log.isDebugEnabled() )log.debug("task : " + r.getClass().getSimpleName() + " completed,Throwable:" + t + ",taskBalance:" + getTaskBalance() );synchronized(this) { notifyAll();}}public void execute( Runnable task) { taskBalance.getAndIncrement();super.execute( task );}/*** 在等待队列未满的情况下，向线程池添加一个任务* @param task 待执行的任务* @return 如果队列满，返回false，否则返回true*/public boolean addTask( Runnable task) { if (queueCapacity < getQueue().size() ) { log.warn("task Queue full!");return false;} else { execute( task );}return true;}/*** @return 未执行的任务数*/public int getTaskBalance() { return taskBalance.get();}/*** @param capacity 要设置的队列容量*/public void setQueueCapacity(int capacity) { this.queueCapacity = capacity;}public void setMaxPoolSize(int size) { super.setMaximumPoolSize(size);}/*** @param time 非核心线程可空闲的秒数*/public void setKeepAliveSecond(int time) { super.setKeepAliveTime(time, TimeUnit.SECONDS);}/*** 挂起当前线程，知道所有的任务都执行完成*/public void waitCompleted(){ try { synchronized( this ){ while( getTaskBalance() > 0 ){ wait( 500 );}}} catch (InterruptedException iex) {}log.info("taskBalance: "+ getTaskBalance() );} }