springboot搭建mybatis配置文件版----连接mysql

51 阅读 0 评论 34 点赞

我是靠谱客的博主幸福时光，最近开发中收集的这篇文章主要介绍springboot搭建mybatis配置文件版----连接mysql，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

一,创建项目

创建一个springboot项目，使用Gradle依赖，添加的依赖为：

compile('org.mybatis.spring.boot:mybatis-spring-boot-starter:1.3.2')
runtime('mysql:mysql-connector-java')
// https://mvnrepository.com/artifact/com.alibaba/druid
compile group: 'com.alibaba', name: 'druid', version: '1.1.9'

二，配置文件

yml:

server:
port: 8080
mybatis:
mapper-locations: classpath:/mybatis/mapper/*.xml
config-location: classpath:/mybatis/mybatis-config.xml
spring:
datasource:
url: jdbc:mysql://localhost:3306/db_mybatis
username: root
password: root
driver-class-name: com.mysql.jdbc.Driver
# 使用druid数据源
type: com.alibaba.druid.pool.DruidDataSource

mybatis-config.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>
<typeAliases>
</typeAliases>
</configuration>

mapper.xml：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.meng.IDAO.UserDao" >
<resultMap id="UserMap" type="com.meng.entity.User" >
<id column="id" property="id" jdbcType="INTEGER" />
<result column="username" property="username" jdbcType="VARCHAR" />
<result column="age" property="age" jdbcType="INTEGER" />
<result column="ctm" property="ctm" jdbcType="TIMESTAMP"/>
</resultMap>
<select id="getByPrimaryKey" parameterType="java.lang.Integer" resultMap="UserMap" >
SELECT *
FROM tb_user
WHERE id = #{id}
</select>
</mapper>

三，数据库设计

CREATE TABLE `tb_user` (
`id` int(11) NOT NULL AUTO_INCREMENT COMMENT 'ID',
`username` varchar(50) NOT NULL COMMENT '用户名',
`age` int(11) NOT NULL COMMENT '年龄',
`ctm` datetime NOT NULL COMMENT '创建时间',
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

四，代码书写

entity:

需要生成getter和setter方法，无参构造器和有参构造器，也可以生成toString方法

import java.util.Date;
private int id;
private String username;
private int age;
private Date ctm;

dao：

通过id来查询用户信息,需加注解@Mapper

@Mapper
public interface UserDao {
    User getByPrimaryKey(@Param("id")Integer id);
}

service：

要点：1.类上面要加@Service

import java.util.List;
import javax.annotation.Resource;
import org.springframework.stereotype.Service;
import com.meng.entity.User;
import com.meng.mapper.UserMapper;
@Service
public class UserService{
@Resource
private UserMapper userMapper;
public User getByPrimaryKey(Integer id) {
return userMapper.getUserById(id);
}
}

controller:

采用Rest风格返回json数据

@RestController
public class UserController {
@Autowired
private UserService uService;
@RequestMapping("/getUser")
public User getUser() {
User u = uService.getUserById(1);
return u;
}
}