RedisDistributedLock 分布式锁

设计一个简单的 RedisDistributedLock 类，实现单例模式，并包含基本的锁定机制。这个类将使用 Redis 来管理锁，确保在分布式系统中资源的同步访问

import redis.clients.jedis.Jedis;

public class RedisDistributedLock {
    private static RedisDistributedLock instance;
    private Jedis jedis;
    private final String redisHost;
    private final int redisPort;

    // 私有构造函数，防止外部实例化
    private RedisDistributedLock(String host, int port) {
        this.redisHost = host;
        this.redisPort = port;
        this.jedis = new Jedis(redisHost, redisPort);
    }

    // 公共静态方法，返回唯一实例
    public static synchronized RedisDistributedLock getSingletonInstance(String host, int port) {
        if (instance == null) {
            instance = new RedisDistributedLock(host, port);
        }
        return instance;
    }

    // 尝试获取锁
    public boolean lockTransaction(String transactionId) {
        String key = "lock:" + transactionId;
        String result = jedis.set(key, "locked", "NX", "EX", 10); // 锁超时时间为10秒
        return "OK".equals(result);
    }

    // 释放锁
    public void unlockTransaction(String transactionId) {
        String key = "lock:" + transactionId;
        jedis.del(key);
    }

    // 清理资源
    public void close() {
        jedis.close();
    }
}