Java读写分离锁实现与应用实践

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.locks.ReentrantReadWriteLock;

public class CacheExample {
    private final Map cache = new HashMap<>();
    private final ReentrantReadWriteLock rwLock = new ReentrantReadWriteLock();

    public Object get(String key) {
        rwLock.readLock().lock();
        try {
            return cache.get(key);
        } finally {
            rwLock.readLock().unlock();
        }
    }

    public void put(String key, Object value) {
        rwLock.writeLock().lock();
        try {
            cache.put(key, value);
        } finally {
            rwLock.writeLock().unlock();
        }
    }
}

public void processData() {
    rwLock.writeLock().lock();
    try {
        // 修改数据
        System.out.println("正在修改数据...");
        
        // 获取读锁（此时仍持有写锁）
        rwLock.readLock().lock();
    } finally {
        // 释放写锁，保留读锁
        rwLock.writeLock().unlock();
    }
    
    try {
        // 执行读操作，其他读线程可以并发进入
        System.out.println("正在读取数据...");
    } finally {
        rwLock.readLock().unlock();
    }
}