Spring boot Mybatis 整合（完整版）

 

 

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SpringBoot系列目录

正题
本项目使用的环境：

开发工具：Intellij IDEA 2017.1.3
springboot: 1.5.6
jdk：1.8.0_161
maven:3.3.9
额外功能

PageHelper 分页插件
mybatis generator 自动生成代码插件
步骤：
1.创建一个springboot项目：

2.创建项目的文件结构以及jdk的版本 

3.选择项目所需要的依赖 

然后点击finish

5.看一下文件的结构： 

6.查看一下pom.xml：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.winter</groupId>
    <artifactId>springboot-mybatis-demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>springboot-mybatis-demo</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.7</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <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>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.35</version>
        </dependency>


        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.datatype</groupId>
            <artifactId>jackson-datatype-joda</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.module</groupId>
            <artifactId>jackson-module-parameter-names</artifactId>
        </dependency>
        <!-- 分页插件 -->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>1.1.2</version>
        </dependency>
        <!-- alibaba的druid数据库连接池 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.0</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <!-- mybatis generator 自动生成代码插件 -->
            <plugin>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-maven-plugin</artifactId>
                <version>1.3.2</version>
                <configuration>
                    <configurationFile>${basedir}/src/main/resources/generator/generatorConfig.xml</configurationFile>
                    <overwrite>true</overwrite>
                    <verbose>true</verbose>
                </configuration>
            </plugin>
        </plugins>
    </build>


</project>

7.项目不使用application.properties文件 而使用更加简洁的application.yml文件： 
将原有的resource文件夹下的application.properties文件删除，创建一个新的application.yml配置文件， 
文件的内容如下：

server:
  port: 8080

spring:
    datasource:
        name: test
        url: jdbc:mysql://127.0.0.1:3306/depot
        username: root
        password: root
        # 使用druid数据源
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.jdbc.Driver
        filters: stat
        maxActive: 20
        initialSize: 1
        maxWait: 60000
        minIdle: 1
        timeBetweenEvictionRunsMillis: 60000
        minEvictableIdleTimeMillis: 300000
        validationQuery: select 'x'
        testWhileIdle: true
        testOnBorrow: false
        testOnReturn: false
        poolPreparedStatements: true
        maxOpenPreparedStatements: 20

## 该配置节点为独立的节点，有很多同学容易将这个配置放在spring的节点下，导致配置无法被识别
mybatis:
  mapper-locations: classpath:mapping/*.xml  #注意：一定要对应mapper映射xml文件的所在路径
  type-aliases-package: com.winter.model  # 注意：对应实体类的路径

#pagehelper分页插件
pagehelper:
    helperDialect: mysql
    reasonable: true
    supportMethodsArguments: true
    params: count=countSql

8.创建数据库：

CREATE DATABASE mytest;

CREATE TABLE t_user(
  user_id INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
  user_name VARCHAR(255) NOT NULL ,
  password VARCHAR(255) NOT NULL ,
  phone VARCHAR(255) NOT NULL
) ENGINE=INNODB AUTO_INCREMENT=1000 DEFAULT CHARSET=utf8;

9.使用mybatis generator 自动生成代码：

• 配置pom.xml中generator 插件所对应的配置文件 ${basedir}/src/main/resources/generator/generatorConfig.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration
        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">
<generatorConfiguration>
    <!-- 数据库驱动:选择你的本地硬盘上面的数据库驱动包-->
    <classPathEntry  location="E:\developer\mybatis-generator-core-1.3.2\lib\mysql-connector-java-5.1.25-bin.jar"/>
    <context id="DB2Tables"  targetRuntime="MyBatis3">
        <commentGenerator>
            <property name="suppressDate" value="true"/>
            <!-- 是否去除自动生成的注释 true：是 ： false:否 -->
            <property name="suppressAllComments" value="true"/>
        </commentGenerator>
        <!--数据库链接URL，用户名、密码 -->
        <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://127.0.0.1/mytest" userId="root" password="root">
        </jdbcConnection>
        <javaTypeResolver>
            <property name="forceBigDecimals" value="false"/>
        </javaTypeResolver>
        <!-- 生成模型的包名和位置-->
        <javaModelGenerator targetPackage="com.winter.model" targetProject="src/main/java">
            <property name="enableSubPackages" value="true"/>
            <property name="trimStrings" value="true"/>
        </javaModelGenerator>
        <!-- 生成映射文件的包名和位置-->
        <sqlMapGenerator targetPackage="mapping" targetProject="src/main/resources">
            <property name="enableSubPackages" value="true"/>
        </sqlMapGenerator>
        <!-- 生成DAO的包名和位置-->
        <javaClientGenerator type="XMLMAPPER" targetPackage="com.winter.mapper" targetProject="src/main/java">
            <property name="enableSubPackages" value="true"/>
        </javaClientGenerator>
        <!-- 要生成的表 tableName是数据库中的表名或视图名 domainObjectName是实体类名-->
        <table tableName="t_user" domainObjectName="User" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"></table>
    </context>
</generatorConfiguration>

• 点击run-Edit Configurations

• 添加配置

• 运行 
  注意！！！同一张表一定不要运行多次，因为mapper的映射文件中会生成多次的代码，导致报错，切记 
  

  最后生成的文件以及结构：

10. 生成的文件

UserMapper.java

package com.winter.mapper;

import com.winter.model.User;

public interface UserMapper {
    int deleteByPrimaryKey(Integer userId);

    int insert(User record);

    int insertSelective(User record);

    User selectByPrimaryKey(Integer userId);

    int updateByPrimaryKeySelective(User record);

    int updateByPrimaryKey(User record);
    //这个方式我自己加的
    List<User> selectAllUser();
}

User.java

package com.winter.model;

public class User {
    private Integer userId;

    private String userName;

    private String password;

    private String phone;

    public Integer getUserId() {
        return userId;
    }

    public void setUserId(Integer userId) {
        this.userId = userId;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName == null ? null : userName.trim();
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password == null ? null : password.trim();
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone == null ? null : phone.trim();
    }
}

对于sql语句这种黄色的背景，真心是看不下去了（解决方案）： 

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="com.winter.mapper.UserMapper" >
  <resultMap id="BaseResultMap" type="com.winter.model.User" >
    <id column="user_id" property="userId" jdbcType="INTEGER" />
    <result column="user_name" property="userName" jdbcType="VARCHAR" />
    <result column="password" property="password" jdbcType="VARCHAR" />
    <result column="phone" property="phone" jdbcType="VARCHAR" />
  </resultMap>
  <sql id="Base_Column_List" >
    user_id, user_name, password, phone
  </sql>
  <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
    select 
    <include refid="Base_Column_List" />
    from t_user
    where user_id = #{userId,jdbcType=INTEGER}
  </select>
  <!-- 这个方法是我自己加的 -->
  <select id="selectAllUser" resultMap="BaseResultMap">
    select
    <include refid="Base_Column_List" />
    from t_user
  </select>
  <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
    delete from t_user
    where user_id = #{userId,jdbcType=INTEGER}
  </delete>
  <insert id="insert" parameterType="com.winter.model.User" >
    insert into t_user (user_id, user_name, password, 
      phone)
    values (#{userId,jdbcType=INTEGER}, #{userName,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR}, 
      #{phone,jdbcType=VARCHAR})
  </insert>
  <insert id="insertSelective" parameterType="com.winter.model.User" >
    insert into t_user
    <trim prefix="(" suffix=")" suffixOverrides="," >
      <if test="userId != null" >
        user_id,
      </if>
      <if test="userName != null" >
        user_name,
      </if>
      <if test="password != null" >
        password,
      </if>
      <if test="phone != null" >
        phone,
      </if>
    </trim>
    <trim prefix="values (" suffix=")" suffixOverrides="," >
      <if test="userId != null" >
        #{userId,jdbcType=INTEGER},
      </if>
      <if test="userName != null" >
        #{userName,jdbcType=VARCHAR},
      </if>
      <if test="password != null" >
        #{password,jdbcType=VARCHAR},
      </if>
      <if test="phone != null" >
        #{phone,jdbcType=VARCHAR},
      </if>
    </trim>
  </insert>
  <update id="updateByPrimaryKeySelective" parameterType="com.winter.model.User" >
    update t_user
    <set >
      <if test="userName != null" >
        user_name = #{userName,jdbcType=VARCHAR},
      </if>
      <if test="password != null" >
        password = #{password,jdbcType=VARCHAR},
      </if>
      <if test="phone != null" >
        phone = #{phone,jdbcType=VARCHAR},
      </if>
    </set>
    where user_id = #{userId,jdbcType=INTEGER}
  </update>
  <update id="updateByPrimaryKey" parameterType="com.winter.model.User" >
    update t_user
    set user_name = #{userName,jdbcType=VARCHAR},
      password = #{password,jdbcType=VARCHAR},
      phone = #{phone,jdbcType=VARCHAR}
    where user_id = #{userId,jdbcType=INTEGER}
  </update>
</mapper>

11.打开类SpringbootMybatisDemoApplication.java，这个是springboot的启动类。我们需要添加点东西：

package com.winter;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@MapperScan("com.winter.mapper")//将项目中对应的mapper类的路径加进来就可以了
public class SpringbootMybatisDemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringbootMybatisDemoApplication.class, args);
    }
}

注意：@MapperScan("com.winter.mapper")这个注解非常的关键，这个对应了项目中mapper（dao）所对应的包路径，很多同学就是这里忘了加导致异常的

12.到这里所有的搭建工作都完成了，接下来就是测试的工作，没使用junit4进行测试：
首先看一下完成之后的文件的结构：

现在controller，service层的代码都写好：

UserController.java

package com.winter.Controller;

import com.winter.model.User;
import com.winter.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

/**
 * Created by Administrator on 2017/8/16.
 */
@Controller
@RequestMapping(value = "/user")
public class UserController {

    @Autowired
    private UserService userService;

    @ResponseBody
    @RequestMapping(value = "/add", produces = {"application/json;charset=UTF-8"})
    public int addUser(User user){
        return userService.addUser(user);
    }

    @ResponseBody
    @RequestMapping(value = "/all/{pageNum}/{pageSize}", produces = {"application/json;charset=UTF-8"})
    public Object findAllUser(@PathVariable("pageNum") int pageNum, @PathVariable("pageSize") int pageSize){

        return userService.findAllUser(pageNum,pageSize);
    }
}

UserService.java

package com.winter.service;

import com.winter.model.User;

import java.util.List;

/**
 * Created by Administrator on 2017/8/16.
 */
public interface UserService {

    int addUser(User user);

    List<User> findAllUser(int pageNum, int pageSize);
}

UserServiceImpl.java

package com.winter.service.impl;

import com.github.pagehelper.PageHelper;
import com.winter.mapper.UserMapper;
import com.winter.model.User;
import com.winter.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

/**
 * Created by Administrator on 2017/8/16.
 */
@Service(value = "userService")
public class UserServiceImpl implements UserService {

    @Autowired
    private UserMapper userMapper;//这里会报错，但是并不会影响

    @Override
    public int addUser(User user) {

        return userMapper.insertSelective(user);
    }

    /*
    * 这个方法中用到了我们开头配置依赖的分页插件pagehelper
    * 很简单，只需要在service层传入参数，然后将参数传递给一个插件的一个静态方法即可；
    * pageNum 开始页数
    * pageSize 每页显示的数据条数
    * */
    @Override
    public List<User> findAllUser(int pageNum, int pageSize) {
        //将参数传给这个方法就可以实现物理分页了，非常简单。
        PageHelper.startPage(pageNum, pageSize);
        return userMapper.selectAllUser();
    }
}

如果强迫症看不下去那个报错：（解决方法）

测试我使用了idea一个很用心的功能。
可以发http请求的插件：

点击左侧的运行按钮就可以发送请求了；
如果返回值正确 说明你已经搭建成功了！！

如果出现mapper注入不了的情况，请检查版本，当前博客的搭建方法只适合1.5.*版本的，如果你的版本是2.0以上的版本，请参照我的另一篇博客的mybatis的配置：springboot2.0整合mybatis

如果大家想使用事务控制的话，请参照Spring boot Mybatis 整合（注解版） ,这个里面就有关于事务控制的使用

源码地址：https://github.com/WinterChenS/springboot-mybatis-demo