public void get() {
		rwl.readLock().lock();
		try {
			System.out.println(Thread.currentThread().getName()
					+ " be ready to read data!");
			Thread.sleep((long) (Math.random() * 1000));
			System.out.println(Thread.currentThread().getName()
					+ "have read data :" + data);
		} catch (InterruptedException e) {
			e.printStackTrace();
		} finally {
			rwl.readLock().unlock();
		}
	}