redis锁，redis分布式锁: RedisLock

最近在做一个项目，类型增减库存的，但是发现我的springboot版本太低，springboot1.5.9版本的，redis是2.9.0的。springboot2.x，redis3.x好的东西用不了。

首先确定你的springboot版本，redis版本。

1.如果不想考虑springboot，redis版本，那么用：Redisson分布式锁。

Redisson分布式锁

引入依赖：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<dependency>
    <groupId>org.redisson</groupId>
    <artifactId>redisson</artifactId>
    <version>3.7.5</version>
</dependency>

　　

application.properties中的相关配置

# Redis服务器地址（默认session使用）
spring.redis.host=192.168.1.201
# Redis服务器连接密码（默认为空）
spring.redis.password=
# Redis服务器连接端口
spring.redis.port=6390

　　

定义一个Loker接口，用于分布式锁的一些操作

import java.util.concurrent.TimeUnit;

/**
 * 锁接口
 * @author jie.zhao
 */
public interface Locker {

    /**
     * 获取锁，如果锁不可用，则当前线程处于休眠状态，直到获得锁为止。
     *
     * @param lockKey
     */
    void lock(String lockKey);

    /**
     * 释放锁
     *
     * @param lockKey
     */
    void unlock(String lockKey);

    /**
     * 获取锁,如果锁不可用，则当前线程处于休眠状态，直到获得锁为止。如果获取到锁后，执行结束后解锁或达到超时时间后会自动释放锁
     *
     * @param lockKey
     * @param timeout
     */
    void lock(String lockKey, int timeout);

    /**
     * 获取锁,如果锁不可用，则当前线程处于休眠状态，直到获得锁为止。如果获取到锁后，执行结束后解锁或达到超时时间后会自动释放锁
     *
     * @param lockKey
     * @param unit
     * @param timeout
     */
    void lock(String lockKey, TimeUnit unit, int timeout);

    /**
     * 尝试获取锁，获取到立即返回true,未获取到立即返回false
     *
     * @param lockKey
     * @return
     */
    boolean tryLock(String lockKey);

    /**
     * 尝试获取锁，在等待时间内获取到锁则返回true,否则返回false,如果获取到锁，则要么执行完后程序释放锁，
     * 要么在给定的超时时间leaseTime后释放锁
     *
     * @param lockKey
     * @param waitTime
     * @param leaseTime
     * @param unit
     * @return
     */
    boolean tryLock(String lockKey, long waitTime, long leaseTime, TimeUnit unit)
            throws InterruptedException;

    /**
     * 锁是否被任意一个线程锁持有
     *
     * @param lockKey
     * @return
     */
    boolean isLocked(String lockKey);

}

　　

实现类RedissonLocker，实现Locker中的方法

import java.util.concurrent.TimeUnit;

import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;

/**
 * 基于Redisson的分布式锁
 * @author jie.zhao
 */
public class RedissonLocker implements Locker {

    private RedissonClient redissonClient;

    public RedissonLocker(RedissonClient redissonClient) {
        super();
        this.redissonClient = redissonClient;
    }

    @Override
    public void lock(String lockKey) {
        RLock lock = redissonClient.getLock(lockKey);
        lock.lock();
    }

    @Override
    public void unlock(String lockKey) {
        RLock lock = redissonClient.getLock(lockKey);
        lock.unlock();
    }

    @Override
    public void lock(String lockKey, int leaseTime) {
        RLock lock = redissonClient.getLock(lockKey);
        lock.lock(leaseTime, TimeUnit.SECONDS);
    }

    @Override
    public void lock(String lockKey, TimeUnit unit, int timeout) {
        RLock lock = redissonClient.getLock(lockKey);
        lock.lock(timeout, unit);
    }

    public void setRedissonClient(RedissonClient redissonClient) {
        this.redissonClient = redissonClient;
    }

    @Override
    public boolean tryLock(String lockKey) {
        RLock lock = redissonClient.getLock(lockKey);
        return lock.tryLock();
    }

    @Override
    public boolean tryLock(String lockKey, long waitTime, long leaseTime,
                           TimeUnit unit) throws InterruptedException {
        RLock lock = redissonClient.getLock(lockKey);
        return lock.tryLock(waitTime, leaseTime, unit);
    }

    @Override
    public boolean isLocked(String lockKey) {
        RLock lock = redissonClient.getLock(lockKey);
        return lock.isLocked();
    }

}

　　

工具类LockUtil

import java.util.concurrent.TimeUnit;

/**
 * redis分布式锁工具类
 * @author jie.zhao
 */
public final class LockUtil {

    private static Locker locker;

    /**
     * 设置工具类使用的locker
     *
     * @param locker
     */
    public static void setLocker(Locker locker) {
        LockUtil.locker = locker;
    }

    /**
     * 获取锁
     *
     * @param lockKey
     */
    public static void lock(String lockKey) {
        locker.lock(lockKey);
    }

    /**
     * 释放锁
     *
     * @param lockKey
     */
    public static void unlock(String lockKey) {
        locker.unlock(lockKey);
    }

    /**
     * 获取锁，超时释放
     *
     * @param lockKey
     * @param timeout
     */
    public static void lock(String lockKey, int timeout) {
        locker.lock(lockKey, timeout);
    }

    /**
     * 获取锁，超时释放，指定时间单位
     *
     * @param lockKey
     * @param unit
     * @param timeout
     */
    public static void lock(String lockKey, TimeUnit unit, int timeout) {
        locker.lock(lockKey, unit, timeout);
    }

    /**
     * 尝试获取锁，获取到立即返回true,获取失败立即返回false
     *
     * @param lockKey
     * @return
     */
    public static boolean tryLock(String lockKey) {
        return locker.tryLock(lockKey);
    }

    /**
     * 尝试获取锁，在给定的waitTime时间内尝试，获取到返回true,获取失败返回false,获取到后再给定的leaseTime时间超时释放
     *
     * @param lockKey
     * @param waitTime
     * @param leaseTime
     * @param unit
     * @return
     * @throws InterruptedException
     */
    public static boolean tryLock(String lockKey, long waitTime, long leaseTime,
                                  TimeUnit unit) throws InterruptedException {
        return locker.tryLock(lockKey, waitTime, leaseTime, unit);
    }

    /**
     * 锁释放被任意一个线程持有
     *
     * @param lockKey
     * @return
     */
    public static boolean isLocked(String lockKey) {
        return locker.isLocked(lockKey);
    }
}

　　

redisson的配置类RedissonConfig

import java.io.IOException;

import com.rxjy.common.redissonlock.LockUtil;
import com.rxjy.common.redissonlock.RedissonLocker;
import org.redisson.Redisson;
import org.redisson.api.RedissonClient;
import org.redisson.config.Config;
import org.redisson.config.SingleServerConfig;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;


@Configuration
public class RedissonConfig {

    @Value("${spring.redis.database}")
    private int database;
    @Value("${spring.redis.host}")
    private String host;
    @Value("${spring.redis.port}")
    private String port;
    @Value("${spring.redis.password}")
    private String password;
    @Value("${spring.redis.timeout}")
    private int timeout;

    /**
     * RedissonClient,单机模式
     *
     * @return
     * @throws IOException
     */
    @Bean(destroyMethod = "shutdown")
    public RedissonClient redisson() {
        Config config = new Config();
        SingleServerConfig singleServerConfig = config.useSingleServer();
        singleServerConfig.setAddress("redis://" + host + ":" + port);
        singleServerConfig.setTimeout(timeout);
        singleServerConfig.setDatabase(database);
        if (password != null && !"".equals(password)) { //有密码
            singleServerConfig.setPassword(password);
        }
        return Redisson.create(config);
    }

    @Bean
    public RedissonLocker redissonLocker(RedissonClient redissonClient) {
        RedissonLocker locker = new RedissonLocker(redissonClient);
        //设置LockUtil的锁处理对象
        LockUtil.setLocker(locker);
        return locker;
    }
}

　　

测试：

import com.rxjy.common.redissonlock.LockUtil;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class RedissonLockTest {

    static final String KEY = "LOCK_KEY";

    @GetMapping("/test")
    public Object test(){
        //加锁
        LockUtil.lock(KEY);
        try {
            //TODO 处理业务
            System.out.println(" 处理业务。。。");
        } catch (Exception e) {
            //异常处理
        }finally{
            //释放锁
            LockUtil.unlock(KEY);
        }

        return "SUCCESS";
    }
}

　　

注意：Redisson中的key,不能有数字，分号，冒号等特殊字符。

可以是这样：test-lock

2.springboot2.x, redis3.x 自己编写RedisLock

RedisLock

VariableKeyLock.java

import java.util.concurrent.locks.Lock;

/**
 * 可变key锁
 *
 */
public interface VariableKeyLock extends Lock {

    boolean tryLock(String key);

    void lock(String key);

    void unlock(String key);
}

　　

RedisLock.java

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.connection.RedisConnection;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.stereotype.Component;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisCluster;

import java.util.Arrays;
import java.util.Random;
import java.util.UUID;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Condition;

/**
 * redis锁
 *
 */
@Component
@Slf4j
public class RedisLock implements VariableKeyLock {

    public static final String LOCK = "LOCK";

    @Autowired
    private RedisConnectionFactory factory;

    private ThreadLocal<String> localValue = new ThreadLocal<String>();

    /**
     * 解锁lua脚本
     */
    private static final String UNLOCK_LUA =
        "if redis.call("get",KEYS[1]) == ARGV[1] then return redis.call("del",KEYS[1]) else return 0 end";

    @Override
    public void lock() {
        if (!tryLock()) {
            try {
                Thread.sleep(new Random().nextInt(10) + 1);
            } catch (InterruptedException e) {
                log.error(e.getMessage(), e);
            }
            lock();
        }
    }

    @Override
    public void lock(String key) {
        if (!tryLock(key)) {
            try {
                Thread.sleep(new Random().nextInt(10) + 1);
            } catch (InterruptedException e) {
                log.error(e.getMessage(), e);
            }
            lock(key);
        }
    }

    @Override
    public boolean tryLock() {
        RedisConnection connection = null;
        try {
            connection = factory.getConnection();
            Jedis jedis = (Jedis)connection.getNativeConnection();
            String value = UUID.randomUUID().toString();
            localValue.set(value);
            String ret = jedis.set(LOCK, value, "NX", "PX", 10000);
            return ret != null && "OK".equals(ret);
        } catch (Exception e) {
            log.error(e.getMessage(), e);
        } finally {
            if (connection != null) {
                connection.close();
            }
        }
        return false;
    }

    @Override
    public boolean tryLock(String key) {
        RedisConnection connection = null;
        try {
            connection = factory.getConnection();
            Jedis jedis = (Jedis)connection.getNativeConnection();
            String value = UUID.randomUUID().toString();
            localValue.set(value);
            String ret = jedis.set(key, value, "NX", "PX", 10000);
            return ret != null && "OK".equals(ret);
        } catch (Exception e) {
            log.error(e.getMessage(), e);
        } finally {
            if (connection != null) {
                connection.close();
            }
        }
        return false;
    }

    @Override
    public void unlock() {
        String script = UNLOCK_LUA;
        RedisConnection connection = null;
        try {
            connection = factory.getConnection();
            Object jedis = connection.getNativeConnection();
            if (jedis instanceof Jedis) {
                ((Jedis)jedis).eval(script, Arrays.asList(LOCK), Arrays.asList(localValue.get()));
            } else if (jedis instanceof JedisCluster) {
                ((JedisCluster)jedis).eval(script, Arrays.asList(LOCK), Arrays.asList(localValue.get()));
            }

        } catch (Exception e) {
            log.error(e.getMessage(), e);
        } finally {
            if (connection != null) {
                connection.close();
            }
        }

    }

    @Override
    public void unlock(String key) {
        String script = UNLOCK_LUA;
        RedisConnection connection = null;
        try {
            connection = factory.getConnection();
            Object jedis = connection.getNativeConnection();
            if (jedis instanceof Jedis) {
                ((Jedis)jedis).eval(script, Arrays.asList(key), Arrays.asList(localValue.get()));
            } else if (jedis instanceof JedisCluster) {
                ((JedisCluster)jedis).eval(script, Arrays.asList(key), Arrays.asList(localValue.get()));
            }
        } catch (Exception e) {
            log.error(e.getMessage(), e);
        } finally {
            if (connection != null) {
                connection.close();
            }
        }
    }

    // -------------------------------------

    @Override
    public void lockInterruptibly() throws InterruptedException {
    }

    @Override
    public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
        return false;
    }

    @Override
    public Condition newCondition() {
        return null;
    }

}

　　

RedisConfig.java配置文件

import com.alibaba.fastjson.parser.ParserConfig;
import com.xxx.common.support.FastJsonSerializationRedisSerializer;
import com.xxx.common.support.log.LogRedisReceiver;
import org.apache.commons.collections.CollectionUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.autoconfigure.data.redis.RedisProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisClusterConfiguration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.connection.RedisPassword;
import org.springframework.data.redis.connection.RedisStandaloneConfiguration;
import org.springframework.data.redis.connection.jedis.JedisClientConfiguration;
import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
import org.springframework.data.redis.core.*;
import org.springframework.data.redis.listener.PatternTopic;
import org.springframework.data.redis.listener.RedisMessageListenerContainer;
import org.springframework.data.redis.listener.adapter.MessageListenerAdapter;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import redis.clients.jedis.JedisPoolConfig;

import java.time.Duration;
import java.util.Optional;

@Configuration
public class RedisConfig {

    @Autowired
    private RedisProperties redisProperties;

    @Value("${spring.application.name}")
    private String applicationName;

    /**
     * 实例化 RedisTemplate 对象
     *
     * @return
     */
    @Bean
    public RedisTemplate<String, Object> functionDomainRedisTemplate() {
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
        initDomainRedisTemplate(redisTemplate, connectionFactory());
        return redisTemplate;
    }

    /**
     * 设置数据存入 redis 的序列化方式
     *
     * @param redisTemplate
     * @param factory
     */
    private void initDomainRedisTemplate(RedisTemplate<String, Object> redisTemplate, RedisConnectionFactory factory) {
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        redisTemplate.setValueSerializer(new FastJsonSerializationRedisSerializer(Object.class));
        //		redisTemplate.setValueSerializer(new JdkSerializationRedisSerializer());
        redisTemplate.setHashKeySerializer(new StringRedisSerializer());
        //		redisTemplate.setHashValueSerializer(new JdkSerializationRedisSerializer());
        redisTemplate.setHashValueSerializer(new FastJsonSerializationRedisSerializer(Object.class));

        ParserConfig.getGlobalInstance().setAutoTypeSupport(true);

        redisTemplate.setConnectionFactory(factory);
    }

    /**
     * 实例化 HashOperations 对象,可以使用 Hash 类型操作
     *
     * @param redisTemplate
     * @return
     */
    @Bean
    public HashOperations<String, String, Object> hashOperations(RedisTemplate<String, Object> redisTemplate) {
        return redisTemplate.opsForHash();
    }

    /**
     * 实例化 ValueOperations 对象,可以使用 String 操作
     *
     * @param redisTemplate
     * @return
     */
    @Bean
    public ValueOperations<String, Object> valueOperations(RedisTemplate<String, Object> redisTemplate) {
        return redisTemplate.opsForValue();
    }

    /**
     * 实例化 ListOperations 对象,可以使用 List 操作
     *
     * @param redisTemplate
     * @return
     */
    @Bean
    public ListOperations<String, Object> listOperations(RedisTemplate<String, Object> redisTemplate) {
        return redisTemplate.opsForList();
    }

    /**
     * 实例化 SetOperations 对象,可以使用 Set 操作
     *
     * @param redisTemplate
     * @return
     */
    @Bean
    public SetOperations<String, Object> setOperations(RedisTemplate<String, Object> redisTemplate) {
        return redisTemplate.opsForSet();
    }

    /**
     * 实例化 ZSetOperations 对象,可以使用 ZSet 操作
     *
     * @param redisTemplate
     * @return
     */
    @Bean
    public ZSetOperations<String, Object> zSetOperations(RedisTemplate<String, Object> redisTemplate) {
        return redisTemplate.opsForZSet();
    }

    @Bean
    public RedisConnectionFactory connectionFactory() {
        JedisPoolConfig poolConfig = new JedisPoolConfig();
        if (redisProperties.getJedis().getPool() != null) {
            poolConfig.setMaxTotal(redisProperties.getJedis().getPool().getMaxActive());
            poolConfig.setMaxIdle(redisProperties.getJedis().getPool().getMaxIdle());
            poolConfig.setMaxWaitMillis(redisProperties.getJedis().getPool().getMaxWait().toMillis());
            poolConfig.setMinIdle(redisProperties.getJedis().getPool().getMinIdle());
        }
        poolConfig.setTestOnBorrow(true);
        poolConfig.setTestOnReturn(false);
        poolConfig.setTestWhileIdle(true);

        JedisClientConfiguration jedisClientConfiguration;
        jedisClientConfiguration = JedisClientConfiguration.builder().usePooling().poolConfig(poolConfig).and()
            .readTimeout(Optional.ofNullable(redisProperties.getTimeout()).orElse(Duration.ofMillis(5000))).build();
        // 如果集群配置未空，则是单机。否则是集群
        if (redisProperties.getCluster() == null || CollectionUtils.isEmpty(redisProperties.getCluster().getNodes())) {
            RedisStandaloneConfiguration redisStandaloneConfiguration = new RedisStandaloneConfiguration();
            redisStandaloneConfiguration.setDatabase(redisProperties.getDatabase());
            redisStandaloneConfiguration.setPort(redisProperties.getPort());
            redisStandaloneConfiguration.setPassword(RedisPassword.of(redisProperties.getPassword()));
            redisStandaloneConfiguration.setHostName(redisProperties.getHost());
            return new JedisConnectionFactory(redisStandaloneConfiguration, jedisClientConfiguration);
        } else {
            RedisClusterConfiguration redisClusterConfiguration =
                new RedisClusterConfiguration(redisProperties.getCluster().getNodes());
            redisClusterConfiguration.setPassword(RedisPassword.of(redisProperties.getPassword()));
            return new JedisConnectionFactory(redisClusterConfiguration, jedisClientConfiguration);
        }
    }

    @Bean
    public RedisMessageListenerContainer container(MessageListenerAdapter listenerAdapter) {
        RedisMessageListenerContainer container = new RedisMessageListenerContainer();
        container.setConnectionFactory(connectionFactory());
        container.addMessageListener(listenerAdapter, new PatternTopic(applicationName + "-log"));
        return container;
    }

    @Bean
    public MessageListenerAdapter listenerAdapter(LogRedisReceiver logRedisReceiver) {
        return new MessageListenerAdapter(logRedisReceiver, "receiveMessage");
    }
}

　　

application.propeties的redis配置，参考spring.redis.*的配置

测试：

      redisLock.lock(RedisKeyConstants.SECKILL_PREX + id );
        try{
            log.debug("increaseSeckillStock-减库存: seckillId-" + seckillId + ",id-"+id);
            try{
                maxPdfNo = seckillInventoryService.deductionInventory(id, seckillId, seckillNo, passengerNum);
            }catch (Exception e){
                e.printStackTrace();
                log.debug("deductionSeckillStock-减库存:" + e.getMessage());
            }
        }finally {
            redisLock.unlock(RedisKeyConstants.SECKILL_PREX + id);
        }