下面是一个简单的基于Redis实现的分布式锁Java代码示例：
import redis.clients.jedis.Jedis;import redis.clients.jedis.params.SetParams;public class DistributedLock {private final Jedis jedis;private final String lockKey;private final String lockValue;private final int expireTime; // 锁过期时间，单位：秒public DistributedLock(Jedis jedis, String lockKey, String lockValue, int expireTime) {this.jedis = jedis;this.lockKey = lockKey;this.lockValue = lockValue;this.expireTime = expireTime;}public boolean tryLock() {SetParams params = new SetParams();params.nx(); // 只有键不存在时才设置值params.ex(expireTime); // 设置过期时间，防止死锁String result = jedis.set(lockKey, lockValue, params);return "OK".equals(result);}public boolean releaseLock() {// Redis不支持原子删除带有特定值的键，需要使用Lua脚本来实现String luaScript = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";Object result = jedis.eval(luaScript, 1, lockKey, lockValue);return (Long) result == 1L;}}
使用示例：
Jedis jedis = new Jedis("localhost", 6379); // 连接到Redis服务器DistributedLock lock = new DistributedLock(jedis, "my-lock", "my-value", 30); // 创建分布式锁if (lock.tryLock()) { // 尝试获取锁try {// 执行需要加锁的代码，同一时刻只能有一个线程执行该代码} finally {lock.releaseLock(); // 释放锁}}
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