spring-data-redis用配置类连接时,抛异常Cannot get Jedis connection; nested exception is

时间:2025-03-22 09:28:40

前提:redis服务器已经运行,且端口号,服务器地址都已经配置正常,但任然抛出无法获取连接异常

原来的代码如下:

 @Bean
    public JedisConnectionFactory connectionFactory(){
        JedisConnectionFactory jedisConnectionFactory = new JedisConnectionFactory();
        (true);
        (jedisPoolConfig());
        ((""));
        ((("")));
        return jedisConnectionFactory;
    }

其他配置都很正常,但是运行后会抛出空指针异常。

Request processing failed; nested exception is : Cannot get Jedis connection; nested exception is 

解决方法如下,在return前添加如下代码

 ();
看源码便知原因:看jedis如何获取到连接的:

public JedisConnection getConnection() {
		Jedis jedis = fetchJedisConnector();
		JedisConnection connection = (usePool ? new JedisConnection(jedis, pool, dbIndex) : new JedisConnection(jedis,
				null, dbIndex));
		(convertPipelineAndTxResults);
		return postProcessConnection(connection);
	}
我们看fetchJedisConnector()方法:

protected Jedis fetchJedisConnector() {
		try {
			if (usePool && pool != null) {
				return ();
			}
			Jedis jedis = new Jedis(getShardInfo());
			// force initialization (see Jedis issue #82)
			();
			return jedis;
		} catch (Exception ex) {
			throw new RedisConnectionFailureException("Cannot get Jedis connection", ex);
		}
	}

如果没用用pool的话,需要用到getShardInfo()方法,而这个方法就是返回一个JedisShardInfo shardInfo。那么这个JedisShardInfo shardInfo在什么时候初始化呢?查看后发现,哈哈在这:

public void afterPropertiesSet() {
		if (shardInfo == null) {
			shardInfo = new JedisShardInfo(hostName, port);

			if ((password)) {
				(password);
			}

			if (timeout > 0) {
				setTimeoutOn(shardInfo, timeout);
			}
		}

		if (usePool) {
			 = createPool();
		}
	}

这个方法将在所有的属性被初始化后调用。但是会在init前调用。是spring中InitializingBean接口的方法。spring-data-redis里面实现了它。在这里对shardIndo类进行了初始化。所以,我们只要在代码中添加:

 ();
这句就可以啦。再运行一次,连接成功!