Java中的ReentrantReadWriteLock使用详解

static ReadWriteLock lock = new ReentrantReadWriteLock();

lock.writeLock().lock();

lock.writeLock().unlock();

lock.readLock().lock();

lock.readLock().unlock();

class ReadWriteLockDemo{
    static ReadWriteLock lock = new ReentrantReadWriteLock();
    static String text = "hello";
    public static void modify(){
        lock.writeLock().lock();
        try {
            System.err.println(Thread.currentThread().getName()+"开始修改");
            text += " "+Thread.currentThread().getName();
        }catch (Exception e){
            e.printStackTrace();
        }
        finally {
            lock.writeLock().unlock();
        }
    }
    public static void readWithReadLock(){
        lock.readLock().lock();
        try {
            System.err.println(text);
            Thread.sleep(5000);
            System.err.println("5秒过去了");
        }catch (Exception e){
        }finally {
            lock.readLock().unlock();
        }
    }
    public static void main(String[] args) throws InterruptedException {
        new Thread(()->{
            readWithReadLock();
        }).start();
        Thread.sleep(1000);
        for (int i=0;i<10;i++) {
            new Thread(() -> {
                modify();
            }).start();
        }
    }
}