Java结合redistemplate使用分布式锁案例讲解

<dependency>  
    <groupId>org.springframework.boot</groupId>  
    <artifactId>spring-boot-starter-data-redis</artifactId>  
</dependency>

# application.properties 示例  
spring.redis.host=localhost  
spring.redis.port=6379  
spring.redis.password= # 如果Redis设置了密码，请填写

import org.springframework.beans.factory.annotation.Autowired;  
import org.springframework.data.redis.core.RedisTemplate;  
import org.springframework.data.redis.core.script.DefaultRedisScript;  
import org.springframework.stereotype.Service;  
import java.util.Collections;  
import java.util.UUID;  
import java.util.concurrent.TimeUnit;  
@Service  
public class RedisLockService {  
    @Autowired  
    private RedisTemplate<String, Object> redisTemplate;  
    private static final String LOCK_PREFIX = "lock:";  
    /**  
     * 尝试获取锁  
     * @param key 锁的key  
     * @param expireTime 锁的过期时间，单位秒  
     * @return 是否获取锁成功  
     */  
    public boolean tryLock(String key, long expireTime) {  
        String requestId = UUID.randomUUID().toString();  
        String result = redisTemplate.opsForValue().setIfAbsent(LOCK_PREFIX + key, requestId, expireTime, TimeUnit.SECONDS);  
        return "OK".equals(result);  
    }  
    /**  
     * 释放锁  
     * @param key 锁的key  
     * @param requestId 请求的唯一标识  
     * @return 是否释放锁成功  
     */  
    public boolean releaseLock(String key, String requestId) {  
        String script = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";  
        Long result = redisTemplate.execute(new DefaultRedisScript<>(script, Long.class), Collections.singletonList(LOCK_PREFIX + key), requestId);  
        return result != null && result > 0;  
    }  
}

@Autowired  
private RedisLockService redisLockService;  
public void criticalSection() {  
    String lockKey = "yourLockKey";  
    try {  
        if (redisLockService.tryLock(lockKey, 10)) { // 尝试获取锁，10秒过期  
            // 执行你的关键代码  
            // ...  
        }  
    } finally {  
        redisLockService.releaseLock(lockKey, requestId); // 释放锁，requestId需要是之前尝试加锁时生成的UUID  
    }  
}