这几天因为需要测试mongodb读写分离的问题，因此写了个定时查询程序，并且用到了多线程，以达到定时启动多个线程查询数据库的效果，下边代码记录备忘：

package timmer;

import java.util.Timer;
import java.util.TimerTask;

import mongoService.mongoServiceImp.AlarmServiceImpl;

import com.mongodb.DBObject;

public class StartTim {

  // 从这里开始测试定时查询
  public static void main(String[] args) {
    Timer timer1 = new Timer();
    // 在1秒后执行此任务,每次间隔5秒执行一次,
    timer1.schedule(new MyTask(), 1000, 5000);
  }

  // java定时器要继承timerTask类
  static class MyTask extends TimerTask {
    AlarmServiceImpl alarmService = new AlarmServiceImpl();

    // 调用定时器需要处理的业务
    public void run() {
      for (int i = 0; i < 3; i++) {
        new Thread(new MyThread(alarmService)).start();
      }
    }
  }

  static class MyThread implements Runnable {
    AlarmServiceImpl alarmService;

    public MyThread(AlarmServiceImpl alarmService) {
      super();
      this.alarmService = alarmService;
    }

    public void run() {
      System.out.println(Thread.currentThread().getName());
      test();
    }

    public void test() {
      System.out.println("定时器");
      DBObject list = alarmService.findAlarm();
      System.out.println(list);
    }
  }
}