import redis.clients.jedis.Jedis;
import java.util.UUID;
 
public class RedisDistributedLock {
    private static final String LOCK_KEY = "lock:resource";  // 鎖的唯一標(biāo)識(shí)
    private static final int EXPIRE_TIME = 10;  // 鎖的超時(shí)時(shí)間，單位：秒
    private static final String REDIS_HOST = "localhost";
    private static final int REDIS_PORT = 6379;
 
    private Jedis jedis;
 
    public RedisDistributedLock() {
        jedis = new Jedis(REDIS_HOST, REDIS_PORT);
    }
 
    // 獲取鎖
    public boolean acquireLock() {
        String lockValue = UUID.randomUUID().toString();  // 唯一的鎖值，防止鎖被誤釋放
 
        // 使用 SETNX 命令獲取鎖
        Long result = jedis.setnx(LOCK_KEY, lockValue);
        
        if (result == 1) {
            // 鎖獲取成功，設(shè)置過期時(shí)間
            jedis.expire(LOCK_KEY, EXPIRE_TIME);
            return true;
        }
 
        // 鎖未獲取成功
        return false;
    }
 
    // 釋放鎖
    public boolean releaseLock() {
        String lockValue = jedis.get(LOCK_KEY);
 
        if (lockValue != null && lockValue.equals(jedis.get(LOCK_KEY))) {
            // 確保當(dāng)前鎖是自己持有的
            jedis.del(LOCK_KEY);
            return true;
        }
 
        return false;
    }
 
    // 關(guān)閉連接
    public void close() {
        jedis.close();
    }
 
    public static void main(String[] args) {
        RedisDistributedLock lock = new RedisDistributedLock();
        
        // 嘗試獲取鎖
        if (lock.acquireLock()) {
            try {
                System.out.println("Lock acquired, performing task.");
                // 執(zhí)行任務(wù)...
                Thread.sleep(5000);  // 模擬任務(wù)處理時(shí)間
            } catch (InterruptedException e) {
                e.printStackTrace();
            } finally {
                lock.releaseLock();  // 完成任務(wù)后釋放鎖
                System.out.println("Lock released.");
            }
        } else {
            System.out.println("Failed to acquire lock, try again later.");
        }
 
        lock.close();
    }
}

import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.redisson.api.Redisson;
import org.redisson.config.Config;
 
public class RedissonLockExample {
    public static void main(String[] args) {
        // 配置 Redisson 客戶端
        Config config = new Config();
        config.useSingleServer().setAddress("redis://127.0.0.1:6379"); // 設(shè)置 Redis 地址
        RedissonClient redisson = Redisson.create(config);  // 創(chuàng)建 Redisson 客戶端
 
        // 獲取分布式鎖
        RLock lock = redisson.getLock("lock:resource");
 
        try {
            // 嘗試獲取鎖
            if (lock.tryLock()) {
                System.out.println("Lock acquired, performing task.");
                // 執(zhí)行任務(wù)...
                Thread.sleep(5000);  // 模擬任務(wù)處理
            } else {
                System.out.println("Failed to acquire lock, try again later.");
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            // 釋放鎖
            lock.unlock();
            redisson.shutdown();  // 關(guān)閉 Redisson 客戶端
            System.out.println("Lock released.");
        }
    }
}

import redis.clients.jedis.Jedis;
 
public class RedisDistributedLockWithLua {
    private static final String LOCK_KEY = "lock:resource";
    private static final int EXPIRE_TIME = 10;  // 鎖的超時(shí)時(shí)間，單位：秒
    private static final String REDIS_HOST = "localhost";
    private static final int REDIS_PORT = 6379;
 
    private Jedis jedis;
 
    public RedisDistributedLockWithLua() {
        jedis = new Jedis(REDIS_HOST, REDIS_PORT);
    }
 
    // 獲取鎖
    public boolean acquireLock(String lockValue) {
        // Lua 腳本：嘗試獲取鎖，如果成功則設(shè)置鎖的過期時(shí)間
        String script = 
            "if redis.call('SETNX', KEYS[1], ARGV[1]) == 1 then " +
            "   redis.call('EXPIRE', KEYS[1], ARGV[2]) " +
            "   return 1 " +
            "else " +
            "   return 0 " +
            "end";
 
        // 使用 EVAL 命令執(zhí)行 Lua 腳本
        Object result = jedis.eval(script, 1, LOCK_KEY, lockValue, String.valueOf(EXPIRE_TIME));
 
        return "1".equals(result.toString());
    }
 
    // 釋放鎖
    public boolean releaseLock(String lockValue) {
        // Lua 腳本：確保當(dāng)前鎖的持有者才會(huì)釋放鎖
        String script = 
            "if redis.call('GET', KEYS[1]) == ARGV[1] then " +
            "   return redis.call('DEL', KEYS[1]) " +
            "else " +
            "   return 0 " +
            "end";
 
        // 使用 EVAL 命令執(zhí)行 Lua 腳本
        Object result = jedis.eval(script, 1, LOCK_KEY, lockValue);
        
        return "1".equals(result.toString());
    }
 
    // 關(guān)閉連接
    public void close() {
        jedis.close();
    }
 
    public static void main(String[] args) {
        RedisDistributedLockWithLua lock = new RedisDistributedLockWithLua();
        String lockValue = "unique-lock-value";  // 唯一的鎖值，用于標(biāo)識(shí)當(dāng)前鎖的擁有者
 
        // 嘗試獲取鎖
        if (lock.acquireLock(lockValue)) {
            try {
                System.out.println("Lock acquired, performing task.");
                // 執(zhí)行任務(wù)...
                Thread.sleep(5000);  // 模擬任務(wù)處理
            } catch (InterruptedException e) {
                e.printStackTrace();
            } finally {
                lock.releaseLock(lockValue);  // 完成任務(wù)后釋放鎖
                System.out.println("Lock released.");
            }
        } else {
            System.out.println("Failed to acquire lock, try again later.");
        }
 
        lock.close();
    }
}