SpringBoot学习10：springboot整合mybatis

需求：通过使用 SpringBoot+SpringMVC+MyBatis 整合实现一个对数据库中的 t_user 表的 CRUD 的操作

1、创建maven项目，添加项目所需依赖

<!--springboot项目依赖的父项目-->

    <parent>

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

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

        <version>2.0.0.RELEASE</version>

    </parent>

    <dependencies>

        <!--注入springboot启动器-->

        <dependency>

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

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

        </dependency>

        <!--注入springboot对thymeleaf视图技术的支持-->

        <dependency>

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

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

        </dependency>

        <!--mybaits启动器，注入springboot对mybatis的支持-->

        <dependency>

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

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

            <version>1.1.1</version>

        </dependency>

        <!-- mysql 数据库驱动 -->

        <dependency>

            <groupId>mysql</groupId>

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

        </dependency>

        <!-- 阿里巴巴druid数据库连接池 -->

        <dependency>

            <groupId>com.alibaba</groupId>

            <artifactId>druid</artifactId>

            <version>1.0.9</version>

        </dependency>

        <!-- jpa实体类规范 -->

        <dependency>

            <groupId>javax.persistence</groupId>

            <artifactId>persistence-api</artifactId>

            <version>1.0</version>

        </dependency>

    </dependencies>

2、在resource文件夹下添加application.properties全局配置文件

#数据库连接信息

spring.datasource.driverClassName=com.mysql.jdbc.Driver

spring.datasource.url=jdbc:mysql://127.0.0.1:3306/springboot

spring.datasource.username=root

spring.datasource.password=duan

#数据库连接池

spring.datasource.type=com.alibaba.druid.pool.DruidDataSource

#配置mybatis中实体类xml配置文件中实体类所在文件夹，如果配置了，在xml配置文件中参数、返回值实体类可以不写包名

mybatis.type-aliases-package=com.bjsxt.pojo

#mapper接口xml文件所在位置

mybatis.mapper-locations=classpath:mapping/*.xml

3、数据库设计

创建数据库

DROP TABLE IF EXISTS `t_user`;

CREATE TABLE `t_user` (

  `id` bigint(10) NOT NULL AUTO_INCREMENT,

  `name` varchar(255) DEFAULT NULL,

  `age` smallint(3) DEFAULT NULL,

  `hobby` varchar(255) DEFAULT NULL,

  PRIMARY KEY (`id`)

) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;

添加数据

INSERT INTO `t_user` VALUES ('1', '张三', '22', '羽毛球');

INSERT INTO `t_user` VALUES ('2', '李四', '20', '篮球');

INSERT INTO `t_user` VALUES ('3', '王五', '24', '排球');

4、创建实体类User

package com.bjsxt.pojo;

import javax.persistence.*;

/**

 * Created by Administrator on 2019/2/10.

 */

@Entity

@Table(name = "t_user")

public class User {

    @Id

    @GeneratedValue(strategy = GenerationType.IDENTITY)

    @Column(name = "id")

    private Long id;

    @Column(name = "name")

    private String name;

    @Column(name = "age")

    private int age;

    @Column(name = "hobby")

    private String hobby;

    public Long getId() {

        return id;

    }

    public void setId(Long id) {

        this.id = id;

    }

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public int getAge() {

        return age;

    }

    public void setAge(int age) {

        this.age = age;

    }

    public String getHobby() {

        return hobby;

    }

    public void setHobby(String hobby) {

        this.hobby = hobby;

    }

}

5、创建mapper接口以及接口映射的配置文件

package com.bjsxt.mapper;

import com.bjsxt.pojo.User;

import org.apache.ibatis.annotations.Mapper;

import java.util.List;

/**

 * Created by Administrator on 2019/2/10.

 */

public interface UserMapper {

    /**

     * 查询所有的用户

     * @return

     */

    List<User> selectAllUser();

    /**

     * 查询单个用户

     */

    User selectUserById(Integer id);

    /**

     * 添加用户

     */

    void addUser(User user);

    /**

     * 修改用户

     */

    void updateUser(User user);

    /**

     * 删除用户

     */

    void deleteUser(Integer id);

}

<?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.bjsxt.mapper.UserMapper">

    <select id="selectAllUser" resultType="User">

        select * from t_user;

    </select>

    <select id="selectUserById" parameterType="java.lang.Integer" resultType="User">

        select * from t_user where id=#{id};

    </select>

    <insert id="addUser" parameterType="User">

        insert into t_user(name,age,hobby) values(#{name},#{age},#{hobby});

    </insert>

    <update id="updateUser" parameterType="User">

        update t_user set name=#{name},age=#{age},hobby=#{hobby} where id=#{id};

    </update>

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

        delete from t_user where id=#{id};

    </delete>

</mapper>

6、创建业务层

接口：

package com.bjsxt.service;

import com.bjsxt.pojo.User;

import java.util.List;

/**

 * Created by Administrator on 2019/2/10.

 */

public interface UserService {

    /**

     * 查询所有的用户

     * @return

     */

    List<User> selectAllUser();

    /**

     * 查询单个用户

     */

    User selectUserById(Integer id);

    /**

     * 添加用户

     */

    void addUser(User user);

    /**

     * 修改用户

     */

    void updateUser(User user);

    /**

     * 删除用户

     */

    void deleteUser(Integer id);

}

实现类

package com.bjsxt.service.impl;

        import com.bjsxt.mapper.UserMapper;

        import com.bjsxt.pojo.User;

        import com.bjsxt.service.UserService;

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

        import org.springframework.stereotype.Service;

        import org.springframework.transaction.annotation.Transactional;

        import java.util.List;

/**

 * Created by Administrator on 2019/2/10.

 */

@Service

@Transactional //service层打开事务

public class UserServiceImpl implements UserService {

    @Autowired

    private UserMapper userMapper;

    @Override

    public List<User> selectAllUser() {

        return userMapper.selectAllUser();

    }

    @Override

    public User selectUserById(Integer id) {

        return userMapper.selectUserById(id);

    }

    @Override

    public void addUser(User user) {

        userMapper.addUser(user);

    }

    @Override

    public void updateUser(User user) {

        userMapper.updateUser(user);

    }

    @Override

    public void deleteUser(Integer id) {

        userMapper.deleteUser(id);

    }

}

7、创建controller

package com.bjsxt.controller;

import com.bjsxt.pojo.User;

import com.bjsxt.service.UserService;

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

import org.springframework.stereotype.Controller;

import org.springframework.ui.Model;

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

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

import javax.servlet.http.HttpServletRequest;

/**

 * Created by Administrator on 2019/2/10.

 */

@Controller

@RequestMapping("user")

public class UserController {

    @Autowired

    private UserService userService;

    /**

     * 去用户列表页面

     * @param model

     * @return

     */

    @RequestMapping("toUserList")

    public String toUserList(Model model){

        model.addAttribute("userList",userService.selectAllUser());

        return "user_list";

    }

    /**

     * 去用户编辑添加页面

     */

    @RequestMapping("toUserEdit")

    public String toUserEdit(HttpServletRequest request,Model model){

        String id=request.getParameter("id");

        if(null!=id&&!"".equals(id)){   //编辑

            User user=userService.selectUserById(Integer.parseInt(id));

            model.addAttribute("user",user);

        }

        return "user_edit";

    }

    /**

     * 用户添加或编辑

     */

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

    public String userEdit(HttpServletRequest request,User user){

        if(null!=user.getId()&&!"".equals(user.getId())){   //编辑

            userService.updateUser(user);

        }else{  //添加

            userService.addUser(user);

        }

        return "redirect:/user/toUserList";

    }

    /**

     * 用户删除

     */

    @RequestMapping("deleteUser")

    public String deleteUser(Integer id){

        userService.deleteUser(id);

        return "redirect:/user/toUserList";

    }

}

8、编写页面，视图层采用thymeleaf技术

用户列表页面user_list.html

<!DOCTYPE html >

<html lang="en" xmlns:th="http://www.thymeleaf.org">

<head>

    <meta charset="UTF-8">

    <title>用户列表</title>

</head>

<body>

    <div>

        <div><a href="toUserEdit">添加</a></div>

        <table>

            <tr>

                <th>用户id</th>

                <th>用户姓名</th>

                <th>用户年龄</th>

                <th>用户爱好</th>

                <th>操作</th>

            </tr>

            <tr th:each="user:${userList}">

                <td th:text="${user.id}"></td>

                <td th:text="${user.name}"></td>

                <td th:text="${user.age}"></td>

                <td th:text="${user.hobby}"></td>

                <td>

                    <a th:href="@{/user/toUserEdit(id=${user.id})}">编辑</a>

                    <a th:href="@{/user/deleteUser(id=${user.id})}">删除</a>

                </td>

            </tr>

        </table>

    </div>

</body>

</html>

用户添加编辑页面user_edit.html

<!DOCTYPE html>

<html lang="en" xmlns:th="http://www.thymeleaf.org">

<head>

    <meta charset="UTF-8">

    <title>用户编辑添加</title>

</head>

<body>

    <form action="/user/userEdit" method="post">

        <input type="hidden" name="id" th:field="${user.id}">

        用户姓名：<input type="text" name="name" th:field="${user.name}"><br />

        用户年龄：<input type="text" name="age" th:field="${user.age}"><br />

        用户爱好：<input type="text" name="hobby" th:field="${user.hobby}"><br />

        <input type="submit" value="提交">

    </form>

</body>

</html>

9、编写启动类

package com.bjsxt;

import org.mybatis.spring.annotation.MapperScan;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

/**

 * Created by Administrator on 2019/2/10.

 */

@SpringBootApplication

@MapperScan("com.bjsxt.mapper") //指定mapper接口所在的位置

public class App {

    public static void main(String[] args){

        SpringApplication.run(App.class,args);

    }

}

在浏览器中访问即可http://localhost:8080/user/toUserList

10、最后目录结构