读写锁的使用个例

public class Test {    static Lock lock = new ReentrantLock();    static ReentrantReadWriteLock readWriteLock = new ReentrantReadWriteLock();    static Lock readLock = readWriteLock.readLock();    static Lock writeLock = readWriteLock.writeLock();    static int value = 0;    static class ReadWriteLockDemo {        public Object handleRead() {            try {                readLock.lock();                Thread.sleep(1000);                System.out.println(System.currentTimeMillis()+" read : "+value);            } catch (InterruptedException e) {                e.printStackTrace();            } finally {                readLock.unlock();            }            return value;        }        public void handleWrite(int val) {            try {                writeLock.lock();                Thread.sleep(1000);                value = val;                System.out.println(System.currentTimeMillis()+" write : "+value);            } catch (InterruptedException e) {                e.printStackTrace();            } finally {                writeLock.unlock();            }        }    }    public static void main(String[] args) throws InterruptedException {        System.out.println(System.currentTimeMillis()+" : "+value);        ReadWriteLockDemo demo = new ReadWriteLockDemo();        Runnable r1 = new Runnable() {            @Override            public void run() {                demo.handleRead();            }        };        Runnable r2 = new Runnable() {                        @Override            public void run() {                demo.handleWrite(new Random().nextInt(100));            }        };        for(int i=0;i<10;i++){            new Thread(r2).start();            new Thread(r1).start();        }    }}