SpringBoot集成Redis和RedisTemplate-数据库

SpringBoot对redis非常友好，不需要像传统项目那样使用Jedis，只要添加spring-boot-starter-data-redis的maven依赖dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-data-r...

SpringBoot对redis非常友好，不需要像传统项目那样使用Jedis，只要添加spring-boot-starter-data-redis的maven依赖

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

接下来是添加redis和RedisTemplate的bean

package com.example.demo.config;

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.cache.interceptor.KeyGenerator;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import java.lang.reflect.Method;

/**
 * @Description:
 * @Author: zhaowang
 * @Date: 2018/10/8 15:42
 * @Version: 1.0
 */
@Configuration
@EnableCaching
public class RedisConfig extends CachingConfigurerSupport {

    @Bean
    public KeyGenerator keyGenerator() {
        return new KeyGenerator() {
            @Override
            public Object generate(Object target, Method method, Object... params) {
                StringBuilder sb = new StringBuilder();
                sb.append(target.getClass().getName());
                sb.append(method.getName());
                for (Object obj : params) {
                    sb.append(obj.toString());
                }
                return sb.toString();
            }
        };
    }



    @Bean(name = "redisTemplate")
    public RedisTemplate<?, ?> redisTemplate(RedisConnectionFactory factory) {
        StringRedisTemplate template = new StringRedisTemplate(factory);
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
        ObjectMapper om = new ObjectMapper();
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jackson2JsonRedisSerializer.setObjectMapper(om);
        template.setValueSerializer(jackson2JsonRedisSerializer);
        template.afterPropertiesSet();
        return template;
    }

}

application.yml配置

spring:
    redis:
        #redis数据库索引(默认为0)
        database: 0
        #redis服务器地址
        host: ip
        #redis服务器连接端口
        port: 6379
        #redis连接密码
        password: 123456

接下来是使用SpringBoot注解实现redis的存取操作的实例

因为使用了Spring Data Jpa，所以这里给出repository层的代码，然后在service层调用该层方法。

package com.example.demo.dao;

import com.example.demo.entity.DatabusEntity;
import org.springframework.cache.annotation.CacheConfig;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Modifying;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.query.Param;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;
import java.util.List;
import java.util.Map;

/**
 * @Description:
 * @Author: zhaowang
 * @Date: 2018/9/21 17:22
 * @Version: 1.0
 */
@Repository
@CacheConfig(cacheNames = "databusEntity")
public interface DatabusDao extends JpaRepository<DatabusEntity, Integer> {


    @Cacheable(key = "#p0", keyGenerator = "myKeyGenerator")
    public DatabusEntity findById(int id);

    @CachePut(key = "#p0.id") // 缓存插入的结果
    @Override
    @Transactional(value="transactionManager")
    public DatabusEntity save(DatabusEntity databusEntity);

    @CacheEvict(key="#p0", allEntries=true) // 删除对应的缓存
    @Transactional(value="transactionManager")
    public void deleteById(int id);


}

注解说明

@CacheConfig(cacheNames = "databusEntity")

cacheNames 指定该类所有方法操作的缓存名称，是全局的。也可以在方法上加，但缓存名称仅对该方法生效，是局部的。

@Cacheable(key = "#p0", keyGenerator = "myKeyGenerator")

1.@Cacheable ：如果方法的第一个参数key(p0)存在于redis缓存中，则从缓存中获取value作为方法的返回结果，否则按照方法定义获取返回结果（一般是查询数据库）。

2.#p0表示第一个参数的key，即保存该方法操作的缓存的key(以HashMap的形式存储）到第一个参数，keyGenerator 定义Key生成的类。

@CachePut(key = "#p0.id"）

p0.id表示将第一个参数的id作为key缓存到redis中，value为第一个参数值。

@CacheEvict(key="#p0", allEntries=true)

1.p0表示删除key为第一个参数的redis缓存数据

2.allEntries=true表示删除缓存中的所有值（key和value）

allEntries=false表示仅删除key对应的value

测试类

package com.example.demo.controller;

import com.example.demo.dao.DatabusDao;
import com.example.demo.domain.DatabusTaskData;
import com.example.demo.entity.DatabusEntity;
import com.example.demo.service.DatabusService;
import com.example.demo.service.DatabusTaskDataService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.*;

/**
 * @Description: test
 * @Author: zhaowang
 * @Date: 2018/8/7 17:46
 * @version: 1.0
 */
@Slf4j
@RestController
@RequestMapping("demo/con")
public class TestController {

    @Autowired
    private DatabusTaskDataService databusTaskDataService;

    @Autowired
    private DatabusService databusService;

    @Autowired
    private DatabusDao databusDao;


     @RequestMapping("/cache")
    public void cache() {

        DatabusEntity databusEntity = databusDao.findById(3073);
        System.out.println("第一次执行："+databusEntity.getFile_name());
        databusEntity.setFile_name("file1");
        databusDao.save(databusEntity);

        DatabusEntity databusEntity2 = databusDao.findById(3073);
        System.out.println("第二次执行："+databusEntity2.getFile_name());

        databusDao.deleteById(3073);
        DatabusEntity databusEntity3 = databusDao.findById(3073);
        if(databusEntity3 != null)
            System.out.println("第三次执行："+databusEntity3.getFile_name());
    }
}

访问url,对比结果可以清晰地知道redis的缓存put和evict的过程。