import java.util.Timer;
import java.util.TimerTask;
import java.util.concurrent.ConcurrentHashMap;


public class ConcurrentHashMapTest {
	
	private static ConcurrentHashMap<String,Timer> timerMap = new ConcurrentHashMap<String,Timer>();
	
	public static void main(String[] args) {
		 for(int i=0;i<100;i++){
	        	new Thread(new Runnable() {
					@Override
					public void run() {
						// TODO Auto-generated method stub
						addTimerTask("1",new TimerTask() {
							@Override
							public void run() {
								// TODO Auto-generated method stub
								System.out.println(Thread.currentThread().getName()+"===="+timerMap.size());
							}
						}, 1000, 1000);
					}
				}).start();;
	        }
	}
	
	
	public static void addTimerTask(String ObjectKey,TimerTask timerTask,long delay, long period){
		if(!timerMap.containsKey(ObjectKey)){
			Timer timer = new Timer();  
			Timer timerOld = timerMap.putIfAbsent(ObjectKey, timer);
			if(timerOld==null){
				System.out.println("我被初始化了>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>");
				timer.schedule(timerTask, delay,period);
			}
		}
	}

}

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