Redis分布式锁的超时机制实现的方法示例

<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
    <version>4.0.1</version>
</dependency>

import redis.clients.jedis.Jedis;
import redis.clients.jedis.params.SetParams;

public class RedisDistributedLock {
    private Jedis jedis;
    private String lockKey;
    private String lockValue;
    private int expireTime;

    public RedisDistributedLock(Jedis jedis, String lockKey, int expireTime) {
        this.jedis = jedis;
        this.lockKey = lockKey;
        this.expireTime = expireTime;
        this.lockValue = String.valueOf(Thread.currentThread().getId());
    }

    public boolean acquireLock() {
        SetParams params = new SetParams();
        params.nx().px(expireTime);
        String result = jedis.set(lockKey, lockValue, params);
        return "OK".equals(result);
    }

    public boolean releaseLock() {
        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 result.equals(1L);
    }
}

public class TestDistributedLock {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("localhost", 6379);
        String lockKey = "distributed_lock";
        RedisDistributedLock lock = new RedisDistributedLock(jedis, lockKey, 10000); // 10秒超时

        if (lock.acquireLock()) {
            try {
                System.out.println("Lock acquired, performing critical operations.");
                // 执行需要同步的操作
                Thread.sleep(5000); // 例如：模拟业务逻辑处理
            } catch (InterruptedException e) {
                e.printStackTrace();
            } finally {
                boolean released = lock.releaseLock();
                if (released) {
                    System.out.println("Lock released.");
                } else {
                    System.out.println("Failed to release lock.");
                }
            }
        } else {
            System.out.println("Failed to acquire lock.");
        }

        jedis.close();
    }
}