java thread worker thread 小例

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import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class WorkThread extends Thread {

    static Log log = LogFactory.getLog(WorkThread.class);

    private Runnable work;

    private boolean exitFlag = false; //是否应该退出

    private ThreadPool tp;

    private boolean isWorkFlag = false;   //是否在"工作",即是否在运行executeContent过程中

    private int threadId;    //ID

    public WorkThread( int threadId ) {
        this.threadId = threadId;
        super.setName( "Thread-" + threadId );
        start();
    }

    public WorkThread( int threadId, ThreadPool tp ) {
        this.threadId = threadId;
        super.setName( "Thread-" + threadId );
        this.tp = tp;
        start();
    }

    public synchronized void run() {

        log.info(this.getName() + " run begin, This worker thread will accept work now.");
        while( true ) {
            try {
                this.wait();
            } catch(Exception e) {
            }
            log.debug("Not wait be notified!!!");
            if( isWorkFlag ) {
                if( work != null) {
                    work.run();
                }
                isWorkFlag = false;
            }
            if( exitFlag ) {
                break;
            }
        }
        log.info(this.getName() + " run end. This worker thread will not accept work now.");

    }

    public synchronized void doAWork(Runnable work) {
        log.debug("###########begin to do work");
        this.isWorkFlag = true;
        this.work = work;
        this.notify();
    }

    /**
     * 工作线程退出
     *
     */
    public synchronized void exit() {
        log.info( this.getName() + " receive exit command, will exit..." );
        this.exitFlag = true;
        this.notify();
    }

    public Runnable getWork() {
        return work;
    }

    public void setWork(Runnable executeContent) {
        this.work = executeContent;
    }

    public boolean isExitFlag() {
        return exitFlag;
    }

    public void setExitFlag(boolean exitFlag) {
        this.exitFlag = exitFlag;
    }

    public boolean isWorkFlag() {
        return isWorkFlag;
    }

    public void setWorkFlag(boolean isWorkFlag) {
        this.isWorkFlag = isWorkFlag;
    }

    public int getThreadId() {
        return threadId;
    }

    public void setThreadId(int threadId) {
        this.threadId = threadId;
    }

    public ThreadPool getTp() {
        return tp;
    }

    public void setTp(ThreadPool tp) {
        this.tp = tp;
    }


    public static void main( String[] args ) {
        Thread t1 = new Thread() {
            public void run() {
                int count = 0;
                while(true) {
                    System.out.println(this.getName() + " running......");
                    try {
                        Thread.sleep(100);
                    } catch(Exception e) {
                    }
                    ++count;
                    if(count >= 10) {
                        break;
                    }
                }
            }
        };


        Thread t2 = new Thread() {
            public void run() {
                int count = 0;
                while(true) {

                    System.out.println(this.getName() + " running......");
                    try {
                        Thread.sleep(100);
                    } catch(Exception e) {
                    }
                    ++count;
                    if(count >= 10) {
                        break;
                    }
                }
            }
        };

        Thread t3 = new Thread() {
            public void run() {
                int count = 0;
                while(true) {

                    System.out.println(this.getName() + " running......");
                    try {
                        Thread.sleep(100);
                    } catch(Exception e) {
                    }
                    ++count;
                    if(count >= 10) {
                        break;
                    }
                }
            }
        };


        WorkThread wt = new WorkThread(999);
        try{
            //Thread.sleep( 1000 );
        } catch(Exception e) {

        }

        wt.doAWork( t1 );
        wt.doAWork( t2 );
        wt.doAWork( t3 );
        wt.doAWork( t3 );
        wt.doAWork( t3 );
        wt.doAWork( t3 );
        wt.doAWork( t2 );
        wt.exit();

    }
}

两个问题:

1. WorkThread wt = new WorkThread(999);
new了之后如果不sleep一点时间,马上就调用doAWork 方法,则可能不执行,因为 wt自身还没有start好的

2. wt.doAWork( t1 ); ....wt.doAWork( t2 );
连续调用这些语句,从第2个开始阻塞,等到第1个work执行完毕, 第2个notify的时候,wt没有马上从sleep状态跳出,也不会去执行第2个,第3个....的内容, 跳过去了. 直到主程序的调用到的一句wt.doAWork( tn )和WorkThread的wait解锁同时发生时,才会到执行那个内容