【强迫症患者必备】SpringBoot项目中Mybatis使用mybatis-redis开启三级缓存必须创建redis.properties优化方案

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前言

Springboot项目中mybatis使用mybatis-redis开启三级缓存需要创建redis.properties优化方案，如何开启三级缓存详见 十分钟带你了解Mybatis一、二、三级缓存，赶紧用起来！。
本文主要解决在使用mybatis-redis开启三级缓存时候，必须强制创建redis.properties文件，这样导致redis配置在多个地方存在，强迫症患者是无法忍受的，下面开始我们的优化改造。

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下载mybatis-redis源码分析

发现mybatis-redis也是实现Cache接口实现三级缓存

RedisCache 代码

public final class RedisCache implements Cache {

  private final ReadWriteLock readWriteLock = new DummyReadWriteLock();

  private String id;

  private static JedisPool pool;

  public RedisCache(final String id) {
    if (id == null) {
      throw new IllegalArgumentException("Cache instances require an ID");
    }
    this.id = id;
    RedisConfig redisConfig = RedisConfigurationBuilder.getInstance().parseConfiguration();
	pool = new JedisPool(redisConfig, redisConfig.getHost(), redisConfig.getPort(),
			redisConfig.getConnectionTimeout(), redisConfig.getSoTimeout(), redisConfig.getPassword(),
			redisConfig.getDatabase(), redisConfig.getClientName());
  }
  。。。。
  略
}

可以看到底层采用jedis做缓存框架，通过RedisConfigurationBuilder.getInstance().parseConfiguration()去获取redis配置

RedisConfigurationBuilder的parseConfiguration方法

public RedisConfig parseConfiguration(ClassLoader classLoader) {
	Properties config = new Properties();

	InputStream input = classLoader.getResourceAsStream(redisPropertiesFilename);
	if (input != null) {
		try {
			config.load(input);
		} catch (IOException e) {
			throw new RuntimeException(
					"An error occurred while reading classpath property '"
							+ redisPropertiesFilename
							+ "', see nested exceptions", e);
		} finally {
			try {
				input.close();
			} catch (IOException e) {
				// close quietly
			}
		}
	}

	RedisConfig jedisConfig = new RedisConfig();
	setConfigProperties(config, jedisConfig);
	return jedisConfig;
}

可以看到这边读取是redisPropertiesFilename文件

上图可以看到默认是redis.properties文件，也可以通过system参数指定，且RedisConfigurationBuilder类是一个final类，基本上没用方法可以处理。因为源码内部只支持properties文件解析，没兼容springboot配置。

优化改造

1.创建JedisConfig类

代码如下：

package com.uhu.redis.cache;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;

import java.time.Duration;

/**
 * @author liujunjie
 * @description
 * @create 2023-11-29 11:54
 **/
@Configuration
@Slf4j
public class JedisConfig {
    @Value("${spring.redis.host}")
    private String host;
    @Value("${spring.redis.port}")
    private int port;
    @Value("${spring.redis.password}")
    private String password;
    @Value("${spring.redis.timeout}")
    private Duration timeout;
    @Value("${spring.redis.jedis.pool.max-active}")
    private int maxActive;
    @Value("${spring.redis.jedis.pool.max-idle}")
    private int maxIdle;
    @Value("${spring.redis.jedis.pool.min-idle}")
    private int minIdle;

    @Bean
    public JedisPool jedisPool() {
        JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
        jedisPoolConfig.setMaxIdle(maxIdle);
        jedisPoolConfig.setMinIdle(minIdle);
        jedisPoolConfig.setMaxTotal(maxActive);
        // 是否启用pool的jmx管理功能, 默认true
        jedisPoolConfig.setJmxEnabled(true);

        JedisPool jedisPool = new JedisPool(jedisPoolConfig, host, port, Integer.parseInt(String.valueOf(timeout.toMillis())), password);
        log.info("JedisPool连接成功:" + host + ":" + port);
        return jedisPool;
    }
}

2.复制RedisCache代码创建自定义的MyRedisCache

代码如下：

/**
 * Copyright 2015 the original author or authors.
 * 

 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 

 * http://www.apache.org/licenses/LICENSE-2.0
 * 

 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.uhu.cache;

import cn.hutool.extra.spring.SpringUtil;
import org.apache.ibatis.cache.Cache;
import org.mybatis.caches.redis.RedisCallback;
import org.mybatis.caches.redis.SerializeUtil;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;

import java.util.Map;

/**
 * Cache adapter for Redis.
 *
 * @author Eduardo Macarron
 */
public class MyRedisCache implements Cache {

    private String id;

    private static JedisPool pool;

    public MyRedisCache(final String id) {
        if (id == null) {
            throw new IllegalArgumentException("Cache instances require an ID");
        }
        this.id = id;
        pool = SpringUtil.getBean(JedisPool.class);
    }

    private Object execute(RedisCallback callback) {

        Jedis jedis = pool.getResource();
        try {
            return callback.doWithRedis(jedis);
        } finally {
            jedis.close();
        }
    }

    @Override
    public String getId() {
        return this.id;
    }

    @Override
    public int getSize() {
        return (Integer) execute(new RedisCallback() {
            @Override
            public Object doWithRedis(Jedis jedis) {
                Map<byte[], byte[]> result = jedis.hgetAll(id.toString().getBytes());
                return result.size();
            }
        });
    }

    @Override
    public void putObject(final Object key, final Object value) {
        execute(new RedisCallback() {
            @Override
            public Object doWithRedis(Jedis jedis) {
                jedis.hset(id.toString().getBytes(), key.toString().getBytes(), SerializeUtil.serialize(value));
                return null;
            }
        });
    }

    @Override
    public Object getObject(final Object key) {
        return execute(new RedisCallback() {
            @Override
            public Object doWithRedis(Jedis jedis) {
                return SerializeUtil.unserialize(jedis.hget(id.toString().getBytes(), key.toString().getBytes()));
            }
        });
    }

    @Override
    public Object removeObject(final Object key) {
        return execute(new RedisCallback() {
            @Override
            public Object doWithRedis(Jedis jedis) {
                return jedis.hdel(id.toString(), key.toString());
            }
        });
    }

    @Override
    public void clear() {
        execute(new RedisCallback() {
            @Override
            public Object doWithRedis(Jedis jedis) {
                jedis.del(id.toString());
                return null;
            }
        });

    }


    @Override
    public String toString() {
        return "Redis {" + id + "}";
    }

}

3.指定缓存实现类为自己的类

xml方式

<mapper namespace="xxx">
     <cache type="com.uhu.redis.cache.MyRedisCache"/>
     
     <select id="findAll" resultType="xxx" useCache="false">
     select>
mapper>

注解方式

@CacheNamespace(implementation = MyRedisCache.class)
@Mapper
public interface XxxDao {
}

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总结

以上就是SpringBoot项目中Mybatis使用mybatis-redis开启三级缓存必须创建redis.properties优化方案，通过简单的源码改造，就可以让许多强迫症患者心情舒畅。