springboot2整合mybatis

项目使用环境

开发工具：Intellij IDEA 2017.1.3

springboot: 2.0.3

jdk：1.8.0_45

maven:3.0.5

额外增加功能

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

4、点击finish

5、查看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.nan</groupId>
<artifactId>blogs</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>

<name>blogs</name>
<description>Demo project for Spring Boot</description>

<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.3.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>1.8</java.version>
</properties>

<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>

<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>1.3.2</version>
</dependency>

<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>

<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.8.0</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.8.8</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.8.8</version>
</dependency>

<!-- 分页插件 -->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>1.2.3</version>
</dependency>
<!-- alibaba的druid数据库连接池 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.0</version>
</dependency>

<dependency> <!--添加通用Mapper依赖 -->
<groupId>tk.mybatis</groupId>
<artifactId>mapper-spring-boot-starter</artifactId>
<version>1.1.4</version>
</dependency>


<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</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>

6、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：

#默认使用配置
spring:
profiles:
active: dev

#公共配置与profiles选择无关 mapperLocations指的路径是src/main/resources
mybatis:
typeAliasesPackage: com.nan.blogs.model
mapperLocations: classpath:mapping/*.xml


---

#开发配置
spring:
profiles: dev

datasource:
url: jdbc:mysql://localhost:3306/blogs
username: root
password: root
driver-class-name: com.mysql.jdbc.Driver
# 使用druid数据源
type: com.alibaba.druid.pool.DruidDataSource


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

7、使用mybatis generator 自动生成代码：

a、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="D:\mavenLib\mysql\mysql-connector-java\5.1.34\mysql-connector-java-5.1.34.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/blogs" 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.nan.blogs.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.nan.blogs.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="user" domainObjectName="User" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"></table>
</context>
</generatorConfiguration>

此处注意可能会报URI IS NOT REGISTER,此时需要将DTD的信息添加到配置中即可

a、打开File—settings ,即可

b、点击run-Edit Configurations

c、添加配置

d、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

8、生成的文件如下：

UserMapper.java

package com.nan.blogs.mapper;

import com.nan.blogs.model.User;

import java.util.List;

public interface UserMapper {
int deleteByPrimaryKey(String id);

int insert(User record);

int insertSelective(User record);

User selectByPrimaryKey(String id);

int updateByPrimaryKeySelective(User record);

int updateByPrimaryKey(User record);
//自己加的
List<User> selectAllUser();
}

user.java

package com.nan.blogs.model;

import java.util.Date;

public class User {
private String id;

private String account;

private Date createddate;

private String email;

private String password;

private String username;

private Integer status;

private Integer blogsstatus;

public String getId() {
return id;
}

public void setId(String id) {
this.id = id == null ? null : id.trim();
}

public String getAccount() {
return account;
}

public void setAccount(String account) {
this.account = account == null ? null : account.trim();
}

public Date getCreateddate() {
return createddate;
}

public void setCreateddate(Date createddate) {
this.createddate = createddate;
}

public String getEmail() {
return email;
}

public void setEmail(String email) {
this.email = email == null ? null : email.trim();
}

public String getPassword() {
return password;
}

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

public String getUsername() {
return username;
}

public void setUsername(String username) {
this.username = username == null ? null : username.trim();
}

public Integer getStatus() {
return status;
}

public void setStatus(Integer status) {
this.status = status;
}

public Integer getBlogsstatus() {
return blogsstatus;
}

public void setBlogsstatus(Integer blogsstatus) {
this.blogsstatus = blogsstatus;
}
}

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.nan.blogs.mapper.UserMapper" >
<resultMap id="BaseResultMap" type="com.nan.blogs.model.User" >
<id column="id" property="id" jdbcType="VARCHAR" />
<result column="account" property="account" jdbcType="VARCHAR" />
<result column="createdDate" property="createddate" jdbcType="TIMESTAMP" />
<result column="email" property="email" jdbcType="VARCHAR" />
<result column="password" property="password" jdbcType="VARCHAR" />
<result column="username" property="username" jdbcType="VARCHAR" />
<result column="status" property="status" jdbcType="INTEGER" />
<result column="blogsStatus" property="blogsstatus" jdbcType="INTEGER" />
</resultMap>
<sql id="Base_Column_List" >
id, account, createdDate, email, password, username, status, blogsStatus
</sql>
<select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.String" >
select 
<include refid="Base_Column_List" />
from user
where id = #{id,jdbcType=VARCHAR}
</select>
<delete id="deleteByPrimaryKey" parameterType="java.lang.String" >
delete from user
where id = #{id,jdbcType=VARCHAR}
</delete>
<insert id="insert" parameterType="com.nan.blogs.model.User" >
insert into user (id, account, createdDate, 
email, password, username, 
status, blogsStatus)
values (#{id,jdbcType=VARCHAR}, #{account,jdbcType=VARCHAR}, #{createddate,jdbcType=TIMESTAMP}, 
#{email,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR}, #{username,jdbcType=VARCHAR}, 
#{status,jdbcType=INTEGER}, #{blogsstatus,jdbcType=INTEGER})
</insert>
<insert id="insertSelective" parameterType="com.nan.blogs.model.User" >
insert into user
<trim prefix="(" suffix=")" suffixOverrides="," >
<if test="id != null" >
id,
</if>
<if test="account != null" >
account,
</if>
<if test="createddate != null" >
createdDate,
</if>
<if test="email != null" >
email,
</if>
<if test="password != null" >
password,
</if>
<if test="username != null" >
username,
</if>
<if test="status != null" >
status,
</if>
<if test="blogsstatus != null" >
blogsStatus,
</if>
</trim>
<trim prefix="values (" suffix=")" suffixOverrides="," >
<if test="id != null" >
#{id,jdbcType=VARCHAR},
</if>
<if test="account != null" >
#{account,jdbcType=VARCHAR},
</if>
<if test="createddate != null" >
#{createddate,jdbcType=TIMESTAMP},
</if>
<if test="email != null" >
#{email,jdbcType=VARCHAR},
</if>
<if test="password != null" >
#{password,jdbcType=VARCHAR},
</if>
<if test="username != null" >
#{username,jdbcType=VARCHAR},
</if>
<if test="status != null" >
#{status,jdbcType=INTEGER},
</if>
<if test="blogsstatus != null" >
#{blogsstatus,jdbcType=INTEGER},
</if>
</trim>
</insert>

<select id="selectAllUser" resultMap="BaseResultMap">
select
<include refid="Base_Column_List" />
form user
</select>

<update id="updateByPrimaryKeySelective" parameterType="com.nan.blogs.model.User" >
update user
<set >
<if test="account != null" >
account = #{account,jdbcType=VARCHAR},
</if>
<if test="createddate != null" >
createdDate = #{createddate,jdbcType=TIMESTAMP},
</if>
<if test="email != null" >
email = #{email,jdbcType=VARCHAR},
</if>
<if test="password != null" >
password = #{password,jdbcType=VARCHAR},
</if>
<if test="username != null" >
username = #{username,jdbcType=VARCHAR},
</if>
<if test="status != null" >
status = #{status,jdbcType=INTEGER},
</if>
<if test="blogsstatus != null" >
blogsStatus = #{blogsstatus,jdbcType=INTEGER},
</if>
</set>
where id = #{id,jdbcType=VARCHAR}
</update>
<update id="updateByPrimaryKey" parameterType="com.nan.blogs.model.User" >
update user
set account = #{account,jdbcType=VARCHAR},
createdDate = #{createddate,jdbcType=TIMESTAMP},
email = #{email,jdbcType=VARCHAR},
password = #{password,jdbcType=VARCHAR},
username = #{username,jdbcType=VARCHAR},
status = #{status,jdbcType=INTEGER},
blogsStatus = #{blogsstatus,jdbcType=INTEGER}
where id = #{id,jdbcType=VARCHAR}
</update>
</mapper>

打开springboot的启动类，需要添加一些东西

package com.nan.blogs;

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

@EnableAutoConfiguration
@SpringBootApplication
@ComponentScan
@MapperScan("com.nan.blogs.mapper")//项目中对应的mapper类的路径加进来就可以了
public class BlogsApplication {

public static void main(String[] args) {
SpringApplication.run(BlogsApplication.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，很多就是这里忘了加导致异常的

9、编写测试类

1、先看编写完之后的项目结构

2、把controller、service的代码写好

controller代码如下：

package com.nan.blogs.controller;

import com.nan.blogs.model.User;
import com.nan.blogs.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;

@Controller
@RequestMapping(value = "/user")
public class UserController {
@Autowired
public UserService userService;

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

/**
* 分页方法
* @param pageNum
* @param pageSize
* @return
*/
@ResponseBody
@RequestMapping(value = "/all/{pageNum}/{pageSize}",produces = {"application/json;charser=UTF-8"})
public Object findAllUser(@PathVariable("pageNum") int pageNum, @PathVariable("pathSize") int pageSize){
return userService.findAllUser(pageNum,pageSize);
}

/**
* 通过id查询用户
* @param id
* @return
*/
@ResponseBody
@RequestMapping(value = "/getId",produces = {"application/json;charser=UTF-8"})
public User getId(String id){
return userService.getId(id);
}
}

service代码

package com.nan.blogs.service;

import com.nan.blogs.model.User;

public interface UserService {
//添加用户信息
int addUser(User user);
//分页查找用户
Object findAllUser(int pageNum, int pageSize);
//通过主键查询用户信息
User getId(String id);
}

serviceImpl代码

package com.nan.blogs.service.impl;

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

@Service
public class UserServiceImpl implements UserService{
@Autowired
private UserMapper userMapper;

/**
* 添加用户信息
* @param user
* @return
*/
@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 Object findAllUser(int pageNum, int pageSize) {
PageHelper.startPage(pageNum,pageSize);
return userMapper.selectAllUser();
}

/**
* 通过主键查询用户信息
* @param id
* @return
*/
@Override
public User getId(String id) {
return userMapper.selectByPrimaryKey(id);
}
}