我爱Java系列---【SpringBoot整合mybatis后开启二级缓存】

1.在yml文件中加上红色部分的配置

server:
  port: 8090
  tomcat:
    uri-encoding: utf-8

spring:
  jackson:
    time-zone: GMT+8
  http:
    encoding:
      charset: UTF-8
      force: true
      enabled: true
  application:
    name: db-local

  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/test?characterEncoding=utf-8
    username: root
    password: root
    initialSize: 5
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
    useGlobalDataSourceStat: true

mybatis:
  type-aliases-package: com.aspire.bigdata.db.domain
  mapper-locations: classpath:mapper/*.xml
  config-location: classpath:config/mybatis.xml //在resource目录下建立config文件夹

2.配置mybatis.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <settings>
      <setting name="logImpl" value="STDOUT_LOGGING"/>
        <!--这个配置使全局的映射器(二级缓存)启用或禁用缓存-->
        <setting name="cacheEnabled" value="true" />
    </settings>
</configuration>

3.测试类

import com.alibaba.fastjson.JSON;
import com.aspire.bigdata.db.domain.User;
import com.aspire.bigdata.db.mapper.UserMapper;
import lombok.extern.slf4j.Slf4j;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import javax.annotation.Resource;

@RunWith(SpringRunner.class)
@SpringBootTest
@Slf4j
public class DbApplicationTests {

    @Resource
    UserMapper userMapper;

    @Test
    public void twoCacheTest() {
        User user1 = userMapper.selectByPrimaryKey(1L);
        log.info("user1:{}", JSON.toJSONString(user1));
        log.info("第一次查询");
        User user2 = userMapper.selectByPrimaryKey(1L);
        log.info("user2:{}", JSON.toJSONString(user2));
        log.info("第二次查询");
        User user3 = userMapper.selectByPrimaryKey(1L);
        log.info("user3:{}", JSON.toJSONString(user3));
        log.info("第三次查询");
        user1.setName("test1");
        userMapper.updateByPrimaryKey(user1);
        User user4 = userMapper.selectByPrimaryKey(1L);
        log.info("user4:{}", JSON.toJSONString(user4));
        log.info("第四次查询");
    }

}