SpringBoot（五） SpringBoot整合mybatis

一：项目结构：

SpringBoot（五） SpringBoot整合mybatis-LMLPHP

二：pom文件如下：

<parent>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-parent</artifactId>

       <version>2.0.4.RELEASE</version>

    </parent>

    <dependencies>

        <!-- Spring-Mybatis -->

        <dependency>

            <groupId>org.mybatis.spring.boot</groupId>

            <artifactId>mybatis-spring-boot-starter</artifactId>

            <version>1.3.0</version>

            </dependency>

        <!-- jdbcTemplate -->

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-jdbc</artifactId>

        </dependency>

        <!-- MySQL连接 -->

        <dependency>

            <groupId>mysql</groupId>

            <artifactId>mysql-connector-java</artifactId>

            <scope>runtime</scope>

        </dependency>

        <!-- Add typical dependencies for a web application -->

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web</artifactId>

        </dependency>

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-test</artifactId>

            <scope>test</scope>

        </dependency>

  </dependencies>

三：数据库配置：

spring:

  datasource:

    driver-class-name: com.mysql.jdbc.Driver

    url: jdbc:mysql://192.168.1.20:3306/test

    username: root

    password: root123

四：代码说明：

最开始使用mybati比较麻烦，各种配置文件、实体类、dao层映射关联、还有一大推其它配置。当然mybatis也发现了这种弊端，初期开发了generator可以根据表结果自动生产实体类、配置文件和dao层代码，可以减轻一部分开发量；后期也进行了大量的优化可以使用注解了。

于是两种使用方式都介绍一下，一、无配置注解版二、配置文件版

1.无配置文件注解版
加入配置文件
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实体类User.class

package cn.saytime.bean;

import java.util.Date;

/**

 * @ClassName cn.saytime.bean.User

 * @Description

 * @date 2017-07-04 22:47:28

 */

public class User {

    private int id;

    private String username;

    private int age;

    private Date ctm;

    public User() {

    }

    public User(String username, int age) {

        this.username = username;

        this.age = age;

        this.ctm = new Date();

    }

    // Getter、Setter

package cn.saytime.mapper;

import cn.saytime.bean.User;

import org.apache.ibatis.annotations.Delete;

import org.apache.ibatis.annotations.Insert;

import org.apache.ibatis.annotations.Param;

import org.apache.ibatis.annotations.Select;

import org.apache.ibatis.annotations.Update;

import java.util.List;

// @Mapper 这里可以使用@Mapper注解，但是每个mapper都加注解比较麻烦，所以统一配置@MapperScan在扫描路径在application类中

public interface UserMapper {

    @Select("SELECT * FROM tb_user WHERE id = #{id}")

    User getUserById(Integer id);

    @Select("SELECT * FROM tb_user")

    public List<User> getUserList();

    @Insert("insert into tb_user(username, age, ctm) values(#{username}, #{age}, now())")

    public int add(User user);

    @Update("UPDATE tb_user SET username = #{user.username} , age = #{user.age} WHERE id = #{id}")

    public int update(@Param("id") Integer id, @Param("user") User user);

    @Delete("DELETE from tb_user where id = #{id} ")

    public int delete(Integer id);

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UserService.class

package cn.saytime.service;

import cn.saytime.bean.User;

import org.springframework.stereotype.Service;

import java.util.List;

/**

 * @ClassName cn.saytime.service.UserService

 * @Description

 */

public interface UserService {

    User getUserById(Integer id);

    public List<User> getUserList();

    public int add(User user);

    public int update(Integer id, User user);

    public int delete(Integer id);

UserServiceimpl.class

package cn.saytime.service.impl;

import cn.saytime.bean.User;

import cn.saytime.mapper.UserMapper;

import cn.saytime.service.UserService;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

import java.util.List;

/**

 * @ClassName cn.saytime.service.impl.UserServiceImpl

 * @Description

 */

@Service

public class UserServiceImpl implements UserService {

    @Autowired

    private UserMapper userMapper;

    @Override

    public User getUserById(Integer id) {

        return userMapper.getUserById(id);

    }

    @Override

    public List<User> getUserList() {

        return userMapper.getUserList();

    }

    @Override

    public int add(User user) {

        return userMapper.add(user);

    }

    @Override

    public int update(Integer id, User user) {

        return userMapper.update(id, user);

    }

    @Override

    public int delete(Integer id) {

        return userMapper.delete(id);

    }

}

JsonResult.class 通用json返回类：

package cn.saytime.bean;

public class JsonResult {

    private String status = null;

    private Object result = null;

    public JsonResult status(String status) {

        this.status = status;

        return this;

    }

    // Getter Setter

UserController.class（Restful风格）

package cn.saytime.web;

import cn.saytime.bean.JsonResult;

import cn.saytime.bean.User;

import cn.saytime.service.UserService;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.http.HttpStatus;

import org.springframework.http.ResponseEntity;

import org.springframework.web.bind.annotation.PathVariable;

import org.springframework.web.bind.annotation.RequestBody;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.RequestParam;

import org.springframework.web.bind.annotation.RestController;

import java.util.List;

/**

 * @ClassName cn.saytime.web.UserController

 * @Description

 * @date 2017-07-04 22:46:14

 */

@RestController

public class UserController {

    @Autowired

    private UserService userService;

    /**

     * 根据ID查询用户

     * @param id

     * @return

     */

    @RequestMapping(value = "user/{id}", method = RequestMethod.GET)

    public ResponseEntity<JsonResult> getUserById (@PathVariable(value = "id") Integer id){

        JsonResult r = new JsonResult();

        try {

            User user = userService.getUserById(id);

            r.setResult(user);

            r.setStatus("ok");

        } catch (Exception e) {

            r.setResult(e.getClass().getName() + ":" + e.getMessage());

            r.setStatus("error");

            e.printStackTrace();

        }

        return ResponseEntity.ok(r);

    }

    /**

     * 查询用户列表

     * @return

     */

    @RequestMapping(value = "users", method = RequestMethod.GET)

    public ResponseEntity<JsonResult> getUserList (){

        JsonResult r = new JsonResult();

        try {

            List<User> users = userService.getUserList();

            r.setResult(users);

            r.setStatus("ok");

        } catch (Exception e) {

            r.setResult(e.getClass().getName() + ":" + e.getMessage());

            r.setStatus("error");

            e.printStackTrace();

        }

        return ResponseEntity.ok(r);

    }

    /**

     * 添加用户

     * @param user

     * @return

     */

    @RequestMapping(value = "user", method = RequestMethod.POST)

    public ResponseEntity<JsonResult> add (@RequestBody User user){

        JsonResult r = new JsonResult();

        try {

            int orderId = userService.add(user);

            if (orderId < 0) {

                r.setResult(orderId);

                r.setStatus("fail");

            } else {

                r.setResult(orderId);

                r.setStatus("ok");

            }

        } catch (Exception e) {

            r.setResult(e.getClass().getName() + ":" + e.getMessage());

            r.setStatus("error");

            e.printStackTrace();

        }

        return ResponseEntity.ok(r);

    }

    /**

     * 根据id删除用户

     * @param id

     * @return

     */

    @RequestMapping(value = "user/{id}", method = RequestMethod.DELETE)

    public ResponseEntity<JsonResult> delete (@PathVariable(value = "id") Integer id){

        JsonResult r = new JsonResult();

        try {

            int ret = userService.delete(id);

            if (ret < 0) {

                r.setResult(ret);

                r.setStatus("fail");

            } else {

                r.setResult(ret);

                r.setStatus("ok");

            }

        } catch (Exception e) {

            r.setResult(e.getClass().getName() + ":" + e.getMessage());

            r.setStatus("error");

            e.printStackTrace();

        }

        return ResponseEntity.ok(r);

    }

    /**

     * 根据id修改用户信息

     * @param user

     * @return

     */

    @RequestMapping(value = "user/{id}", method = RequestMethod.PUT)

    public ResponseEntity<JsonResult> update (@PathVariable("id") Integer id, @RequestBody User user){

        JsonResult r = new JsonResult();

        try {

            int ret = userService.update(id, user);

            if (ret < 0) {

                r.setResult(ret);

                r.setStatus("fail");

            } else {

                r.setResult(ret);

                r.setStatus("ok");

            }

        } catch (Exception e) {

            r.setResult(e.getClass().getName() + ":" + e.getMessage());

            r.setStatus("error");

            e.printStackTrace();

        }

        return ResponseEntity.ok(r);

    }

}

Application.java

package cn.saytime;

import org.mybatis.spring.annotation.MapperScan;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication

@MapperScan("cn.saytime.mapper")

public class SpringbootMybaitsApplication {

    public static void main(String[] args) {

        SpringApplication.run(SpringbootMybaitsApplication.class, args);

    }

测试：

使用PostMan通过测试： http://localhost:8080/user/1

2.配置文件版

加入配置文件

SpringBoot（五） SpringBoot整合mybatis-LMLPHP

代码部分，相比于上面那种方式，改变的只有配置文件以及下面几个部分UserMapper.class

package cn.saytime.mapper;

import cn.saytime.bean.User;

import org.apache.ibatis.annotations.Delete;

import org.apache.ibatis.annotations.Insert;

import org.apache.ibatis.annotations.Param;

import org.apache.ibatis.annotations.Select;

import org.apache.ibatis.annotations.Update;

import org.springframework.stereotype.Repository;

import java.util.List;

/**

 * @ClassName cn.saytime.mapper.UesrMapper

 * @Description

 */

@Repository

public interface UserMapper {

    User getUserById(Integer id);

    public List<User> getUserList();

    public int add(User user);

    public int update(@Param("id") Integer id, @Param("user") User user);

    public int delete(Integer id);

}

UserServiceImpl类：

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

import com.demo.dao.UserDao;
import com.demo.mapper.User;
import com.demo.mapper.UserMapper1;
import com.demo.service.UserService;

@Service
public class UserServiceImpl implements UserService{

@Autowired
private UserDao userDao;

@Autowired
private UserMapper1 userMapper;

@Override
public User getUserById(Integer id) {
return userMapper.getUserById(id);
}

@Override
public List<User> getUserList() {
return userMapper.getUserList();
}

}

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>

userMapper.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="cn.saytime.mapper.UserMapper" >

    <resultMap id="BaseResultMap" type="cn.saytime.bean.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>

    <sql id="Base_Column_List" >

        id, username, age, ctm

    </sql>

    <select id="getUserList" resultMap="BaseResultMap"  >

        SELECT

        <include refid="Base_Column_List" />

        FROM tb_user

    </select>

    <select id="getUserById" parameterType="java.lang.Integer" resultMap="BaseResultMap" >

        SELECT

        <include refid="Base_Column_List" />

        FROM tb_user

        WHERE id = #{id}

    </select>

    <insert id="add" parameterType="cn.saytime.bean.User" >

        INSERT INTO

        tb_user

        (username,age,ctm)

        VALUES

        (#{username}, #{age}, now())

    </insert>

    <update id="update" parameterType="java.util.Map" >

        UPDATE

        tb_user

        SET

        username = #{user.username},age = #{user.age}

        WHERE

        id = #{id}

    </update>

    <delete id="delete" parameterType="java.lang.Integer" >

        DELETE FROM

        tb_user

        WHERE

        id = #{id}

    </delete>

</mapper>

测试方法同上：http://localhost:8080/user/1

五、简要说明：
不知道大家有没有注意到一点，就是引入Springboot-mybatis依赖的时候，并不是spring官方的starter，往常的springboot集成的依赖，比如web，redis等，groupId以及artifactId的地址如下：

<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
而这里是mybatis为spring提供的starter依赖，所以依赖地址是：

<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.0</version>
</dependency>
而且值得注意的是，这里必须要指定版本号，往常我们使用springboot之所以不需要指定版本号，是因为我们引入的Maven Parent 中指定了SpringBoot的依赖，SpringBoot官方依赖Pom文件中已经指定了它自己集成的第三方依赖的版本号，对于Mybatis，Spring官方并没有提供自己的starter，所以必须跟正常的maven依赖一样，要加版本号。
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