多線程統計器

題目：設計多線程統計器。啓動N個線程,線程執行時，打印每一個線程執行的次數，和全部線程執行次數和

不對的地方，或者更好的，望指點。

package lcr;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.locks.ReentrantLock;

import com.google.common.util.concurrent.AtomicLongMap;

public class MultiThreadCounter {

	private static MultiThreadCounter pvs = null;

	private static ScheduledExecutorService service = null;

	private static ReentrantLock lock = new ReentrantLock();

	private static AtomicLongMap<String> pvCounterMap = AtomicLongMap.create();

	private static int MONITOR_INITIAL_DELAY_SECONDS = 3; // 監控初始延遲秒數
	private static int MONITOR_INTERVAL_SECONDS = 10; // 監控間隔秒數
	private static Map<String, Long> map2 = new HashMap<String, Long>();

	private static AtomicInteger atomic = new AtomicInteger(0);
	
	public long lncr(String key) {
		long result = -1;
		while (true) {
			if (!lock.isLocked()) {
				result = pvCounterMap.incrementAndGet(key);
				atomic.incrementAndGet();
				break;
			} else {
				try {
					TimeUnit.MILLISECONDS.sleep(10);
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}

		}
		return result;
	}

	public MultiThreadCounter() {
		createExecutorService();
		startMonitor();
	}

	public static MultiThreadCounter newInstance() {
		if (pvs == null) {
			synchronized (MultiThreadCounter.class) {
				if (pvs == null) {
					pvs = new MultiThreadCounter();
				}
			}
		}
		return pvs;
	}

	private void startMonitor() {
		service.scheduleWithFixedDelay(new StatMonitorRunner(), MONITOR_INITIAL_DELAY_SECONDS, MONITOR_INTERVAL_SECONDS,
				TimeUnit.SECONDS);
	}

	private void createExecutorService() {
		if (service == null) {
			service = Executors.newScheduledThreadPool(1, new ThreadFactory() {
				@Override
				public Thread newThread(Runnable r) {
					Thread thread = new Thread(r);
					thread.setDaemon(true); // 宿主線程
					return thread;
				}
			});
		}
	}

	private Map<String, Long> popCounter() {
		Map<String, Long> newMap = new HashMap<String, Long>();  
		lock.lock();  
		try {
			for (Iterator<String> it = pvCounterMap.asMap().keySet().iterator(); it.hasNext();) {
				String key = it.next();
				newMap.put(key, pvCounterMap.get(key));
			}
			pvCounterMap.clear();
		} finally{
			lock.unlock();
		}
		return newMap;
	}

	class StatMonitorRunner implements Runnable {

		@Override
		public void run() {
			Map<String, Long> map = popCounter();
			for(Iterator<String> it = map.keySet().iterator(); it.hasNext(); ){  
				String key = it.next();
				if(map2.containsKey(key)) {
					map2.put(key, new Long(map2.get(key).longValue()+map.get(key).longValue()));
				}else {
					map2.put(key, map.get(key));
				}
			}
			System.out.println("結果："+map2);
			System.out.println("總計數："+atomic.get());
		}

	}

}

package lcr;

import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

public class CounterTest {

	public static void main(String[] args) {
		ScheduledExecutorService service = Executors.newScheduledThreadPool(6);  
		for (int i = 0; i < 6; i++) {
			CounterTest t = new CounterTest();
			String name = "name"+i;
			service.scheduleWithFixedDelay(t.new MyRunner(name), 0, 1000, TimeUnit.MILLISECONDS);
		}
		
		
	}
	class MyRunner implements Runnable{
		
		private String name;
		
		public MyRunner(String name) {
			this.name = name;
		}



		@Override
		public void run() {
			long l =  MultiThreadCounter.newInstance().lncr(this.name);
			//System.out.println(this.name+" > " + l);
		}
		
	}
}