线程池完成加一减一作业题

package cn.everest.threadpool;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class ShareDateAndThreadPool {

	public static void main(String[] args) {

		Resource resource = new Resource();
		IncreData increData = new IncreData(resource);
		DecreData decreData = new DecreData(resource);

		ExecutorService threadPool1 = Executors.newCachedThreadPool();
		ExecutorService threadPool2 = Executors.newCachedThreadPool();
		
		for (int i = 0; i < 2; i++) {
			threadPool1.execute(increData);
		}
		for (int i = 0; i < 2; i++) {
			threadPool2.execute(decreData);
		}
	
		threadPool1.shutdown();
		threadPool2.shutdown();
	
	} // end main
	
} // end ShareDateAndThreadPool

class IncreData implements Runnable {
	private Resource resource;

	public IncreData(Resource resource) {
		this.resource = resource;
	}

	@Override
	public void run() {
		for (int i = 0; i < 50; i++) {
			resource.increment();
		}
	}
}

class DecreData implements Runnable {
	private Resource resource;

	public DecreData(Resource resource) {
		this.resource = resource;
	}

	@Override
	public void run() {
		for (int i = 0; i < 50; i++) {
			resource.decrement();
		}
	}
}

class Resource {
	private int x = 0;
	private boolean flag = false;

	public Resource() {
	}

	final Lock lock = new ReentrantLock();
	Condition increCondition = lock.newCondition();
	Condition decreCondition = lock.newCondition();

	public void increment() {
		lock.lock();
		try {
			while (flag) {
				increCondition.await();
			}
			x = x + 1;
			System.out.println(Thread.currentThread().getName() + " x +++++++++++++++++++++++: " + x);
			flag = !flag;
			decreCondition.signal();
		} catch (InterruptedException e) {
			e.printStackTrace();
		} finally {
			lock.unlock();
		}
	} // end increment

	public void decrement() {
		lock.lock();
		try {
			while (!flag) {
				decreCondition.await();
			}
			x = x - 1;
			System.out.println(Thread.currentThread().getName() + " x ------------: " + x);
			flag = !flag;
			increCondition.signal();
		} catch (InterruptedException e) {
			e.printStackTrace();
		} finally {
			lock.unlock();
		}
	} // end decrement
	
} // end Resource