Java写的一个定时器，多线程：

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package javaapplication1;

import static java.lang.Thread.sleep;
import java.nio.ByteBuffer;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.HashMap;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author Qyee
 */
public class JavaApplication1 {
    private static final Object lock = new Object();
    private static Thread execTrhead;
    private static AtomicBoolean bRunning = new AtomicBoolean(false);

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws ParseException, InterruptedException {
        // TODO code application logic here

        execTrhead = new Thread(new Runnable() {
            public void run() {
                do {
                    bRunning.set(true);
                    System.out.println("doing 1");
                    synchronized (lock) {
                        try {
                            lock.wait(1000);
                        } catch (InterruptedException ex) {
                            Logger.getLogger(JavaApplication1.class.getName()).log(Level.SEVERE, null, ex);
                        }
                    }
                    System.out.println("doing 2");
                } while (bRunning.get());
            }
        });
        execTrhead.start();

        while (true) {
            System.out.println("notify");
            sleep(2000);
            synchronized (lock) {
                lock.notify();
            }
        }
    }
}