Spring集成redis下如何获取访问redis服务端的Jedis实例

爱被打了一巴掌 2023-07-09 11:25 54阅读 0赞

##### 1.RedisTemplate介绍 #####

Spring为了更加方便操作redis，对redis操作进行封装，maven依赖如下：

<dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-redis</artifactId>
        <version>1.8.18.RELEASE</version>
    </dependency>

RedisTemplate是Spring封装用来操作redis的模板工具类，封装了我们常用的redis操作，例如：set、get、hset、hget等

##### 2.如何获取Jedis实例 #####

###### 2.1 背景 ######

redis实现分布式锁，其中需要Jedis实例，其中核心用到的Jedis\#set()方法如下：

/** * Set the string value as value of the key. The string can't be longer than 1073741824 bytes (1 * GB). * @param key * @param value * @param nxxx NX|XX, NX -- Only set the key if it does not already exist. XX -- Only set the key * if it already exist. * @param expx EX|PX, expire time units: EX = seconds; PX = milliseconds * @param time expire time in the units of <code>expx</code> * @return Status code reply */
    public String set(final String key, final String value, final String nxxx, final String expx,
                      final long time) { 
        checkIsInMultiOrPipeline();
        client.set(key, value, nxxx, expx, time);
        return client.getStatusCodeReply();
    }

##### 2.2 Spring集成redis配置文件 #####

> 1.单机部署

redis-config.xml文件如下 ：

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd">
    
        
        <bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig">
            <property name="minIdle" value="${jedis.pool.minIdle}"/>
            <property name="maxIdle" value="${jedis.pool.maxIdle}"/>
            <property name="maxTotal" value="${jedis.pool.maxTotal}"/>
            <property name="maxWaitMillis" value="${jedis.pool.maxWaitMillis}"/>
            <property name="testOnBorrow" value="${jedis.pool.testOnBorrow}"/>
        </bean>
    
        
        <bean id="jedisConnectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory" destroy-method="destroy">
            <property name="poolConfig" ref="poolConfig"/>
            <property name="port" value="${redis.port}"/>
            <property name="hostName" value="${redis.host}"/>
            <property name="password" value="${redis.password}"/>
            <property name="database" value="${redis.database}"/>
            <property name="timeout" value="${redis.timeout}"/>
        </bean>
    
        <bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate">
            <property name="connectionFactory" ref="jedisConnectionFactory"/>
            <property name="keySerializer" >
                <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" />
            </property>
            <property name="hashKeySerializer">
                <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" />
            </property>
            <property name="valueSerializer" >
                <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" />
            </property>
            <property name="hashValueSerializer">
                <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" />
            </property>
        </bean>
    </beans>

> 2.多机部署（redis集群，多节点）

redis-cluster-config.xml 如下：

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd">
    
        
        <bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig">
            <property name="minIdle" value="${jedis.pool.minIdle}"/>
            <property name="maxIdle" value="${jedis.pool.maxIdle}"/>
            <property name="maxTotal" value="${jedis.pool.maxTotal}"/>
            <property name="maxWaitMillis" value="${jedis.pool.maxWaitMillis}"/>
            <property name="testOnBorrow" value="${jedis.pool.testOnBorrow}"/>
        </bean>
    
        
        <bean id="resourcePropertySource" class="org.springframework.core.io.support.ResourcePropertySource">
            <constructor-arg name="name" value="redis.properties"/>
            <constructor-arg name="resource" value="classpath:/profile/run/redis.properties"/>
        </bean>
    
        
        <bean id="redisClusterConfiguration" class="org.springframework.data.redis.connection.RedisClusterConfiguration">
            <constructor-arg name="propertySource" ref="resourcePropertySource"/>
        </bean>
    
        
        <bean id="jedisConnectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory" destroy-method="destroy">
            <constructor-arg name="clusterConfig" ref="redisClusterConfiguration"/>
            <constructor-arg name="poolConfig" ref="poolConfig"/>
            <property name="password" value="${spring.redis.password}"/>
            <property name="timeout" value="${spring.redis.timeout}"/>
        </bean>
    
        <bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate">
            <property name="connectionFactory" ref="jedisConnectionFactory"/>
            <property name="keySerializer" >
                <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" />
            </property>
            <property name="hashKeySerializer">
                <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" />
            </property>
            <property name="valueSerializer" >
                <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" />
            </property>
            <property name="hashValueSerializer">
                <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" />
            </property>
        </bean>
    </beans>

**注意：**

*  单机部署和多机部署都需要配置JedisConnectionFactory（Jedis连接工厂），我们通过JedisConnectionFactory获取Jedis实例

###### 2.3 获取Jedis实例 ######

根据Jedis连接工厂获取Jedis连接池，然后从连接池中获取Jedis实例，代码如下：

@Component
    public class RedisTool implements InitializingBean { 
    
        private static final Long RELEASE_SUCCESS = 1L;
        private static final String LOCK_SUCCESS = "OK";
        private static final String SET_IF_NOT_EXIST = "NX";
        // EX|PX, expire time units: EX = seconds; PX = milliseconds
        private static final String SET_WITH_EXPIRE_TIME = "PX";
    
        @Autowired
        JedisConnectionFactory jedisConnectionFactory;
    
        private JedisPool jedisPool;;
    
        /** * 从JedisPool中获取Jedis实例。注意：Jedis实例用完以后需要回收至JedisPool * * @return * @throws Exception */
        public Jedis getJedis() throws Exception { 
            if (jedisPool == null) { 
                afterPropertiesSet();
            }
            return jedisPool.getResource();
        }
    
        @Override
        public void afterPropertiesSet() throws Exception { 
            Field pool = ReflectionUtils.findField(JedisConnectionFactory.class, "pool");
            ReflectionUtils.makeAccessible(pool);
            jedisPool = (JedisPool) ReflectionUtils.getField(pool, jedisConnectionFactory);
        }
    
    }