ReentrantReadWriteLock读写锁

代码：

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

//写，原子独占
class MyCache {
    private volatile Map<String, Object> map=new HashMap<>();
    //private Lock lock = new ReentrantLock();//写的时候一个线程，读的时候多个线程
    private ReentrantReadWriteLock rwLock=new ReentrantReadWriteLock();

    public void put(String key,Object value){
        rwLock.writeLock().lock();
        try {
            System.out.println(Thread.currentThread().getName()+"	 正在写入："+key);
            try {
                TimeUnit.MILLISECONDS.sleep(300);
            }catch (InterruptedException e){
                e.printStackTrace();
            }
            map.put(key,value);
            System.out.println(Thread.currentThread().getName()+"	 写入："+key);
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            rwLock.writeLock().unlock();
        }
    }

    public void get(String key){
        rwLock.readLock().lock();
        try {
            System.out.println(Thread.currentThread().getName()+"	 正在读取："+key);
            try {
                TimeUnit.MILLISECONDS.sleep(300);
            }catch (InterruptedException e){
                e.printStackTrace();
            }
            Object result=map.get(key);
            System.out.println(Thread.currentThread().getName()+"	 读取完成："+result);
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            rwLock.readLock().unlock();
        }
    }
}
public class ReadWriteLockDemo {
    public static void main(String[] args) {
        MyCache myCache=new MyCache();
        for (int i=0;i<=5;i++){
            final int tempInt=i;
            new Thread(()->{
                myCache.put(tempInt+"",tempInt+"");
            },String.valueOf(i)).start();
        }
        for(int i=1;i<=5;i++){
            final int tempInt=i;
            new Thread(()->{
                myCache.get(tempInt+"");
            },String.valueOf(i)).start();
        }
    }
}