Spring Boot集成Mybatis

1. 配置pom.xml

引入mybatis-spring-boot-starter。

<parent>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-parent</artifactId>    <version>1.3.5.RELEASE</version>    <relativePath /></parent><properties>    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>    <java.version>1.8</java.version></properties><dependencies>    <dependency>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-web</artifactId>    </dependency>    <dependency>        <groupId>org.mybatis.spring.boot</groupId>        <artifactId>mybatis-spring-boot-starter</artifactId>        <version>1.1.1</version>    </dependency>    <dependency>        <groupId>com.alibaba</groupId>        <artifactId>druid</artifactId>        <version>1.0.20</version>    </dependency>    <dependency>        <groupId>org.postgresql</groupId>        <artifactId>postgresql</artifactId>        <scope>runtime</scope>    </dependency></dependencies>

2. 在application.properties中增加mybatis配置

#mybatis#entity扫描的包名mybatis.type-aliases-package=com.xiaolyuh.domain.model#Mapper.xml所在的位置mybatis.mapper-locations=classpath*:/META-INF/mybaits/*Mapper.xml

3. 代码

3.1 User实体

根据application.properties中的定义，包名为com.example.entity

public class User {    private Integer id;    private String username;    //省略了setters & getters}

3.2 UserMapper接口

注意不要忘记写@Mapper。

@Mapperpublic interface UserMapper {    User selectUser(Integer id);    User selectAllUsers();    void insertUser(User user);    void updateUser(User user);    void deleteUser(User user);}

3.3 UserMapper.xml

根据application.properties中的定义，UserMapper.xml位于src/main/resources/mappers目录下。

<?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.example.dao.UserMapper">    <resultMap type="User" id="userResultMap">        <id property="id" column="id" />        <result property="username" column="username" />    </resultMap>    <select id="selectUser" resultType="User" resultMap="userResultMap">        select id, username from t_user where id = #{id}    </select>    <select id="selectAllUsers" resultType="User" resultMap="userResultMap">        select id, username from t_user    </select>    <insert id="insertUser" parameterType="User">        insert into t_user (id, username ) values (#{id},#{username})    </insert>    <update id="updateUser" parameterType="User">        update t_user        <set>            <if test="username != null ">                username = #{username},            </if>        </set>        where id = #{id}    </update>    <delete id="deleteUser" parameterType="User">        delete from t_user where id = #{id}    </delete></mapper>

3.4 UserController

@RestController@RequestMapping("/user")public class UserController {    @Autowired    UserMapper userMapper;    @RequestMapping(value = "/add.do", method = RequestMethod.POST)    public User add(@RequestParam(value = "id", required = true) Integer id,            @RequestParam(value = "username", required = true) String username) {        User user = new User();        user.setId(id);        user.setUsername(username);        userMapper.insertUser(user);        return user;    }    @RequestMapping(value = "/query.do", method = RequestMethod.GET)    public User query(@RequestParam(value = "id", required = true) Integer id) {        return  userMapper.selectUser(id);    }}