spring-boot2-整合（一）Mybatis-（特别完整！）

整合Mybatis分为两种模式，一种是xml配置，一种是注解。（类似JPA）

我在这里重点放在xml配置上，因为如果想用注解的话，建议直接用jpa代替，因为Jpa有更成熟的CRUD接口更方便开发。我在后文中也会把注解方式说清楚。

大概介绍下流程：

1. 借助idea实现mybatis逆向工程

2. 用xml配置实现整合

3. 用cmd命令行实现mybatis逆向工程

4. 用mapping.xml配置实现数据交互

5. 用注解的方式实现数据交互

首先我的开发环境：

jdk1.8+maven3+IDEA

1. mybatis逆向攻城

逆向工程方式很多，我目前接触到的就两种，一种是借助于ide开发工具，一种是在cmd中执行命令。（其实二者原理都一样，都是执行maven的generator命令，具体请看下文）。

1. 完善pom文件

<?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>springboot-mybatis</groupId>
<artifactId>springboot-mybatis</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>

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

<parent>
<groupId>springboot-integration</groupId>
<artifactId>springboot-integration</artifactId>
<version>1.0-SNAPSHOT</version>
</parent>

<!-- Add typical dependencies for a web application -->
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<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>
<!-- alibaba的druid数据库连接池 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.0.11</version>
</dependency>
<!-- alibaba的d
4000
ruid数据库连接池 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.0</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<scope>test</scope>
</dependency>
<!-- 分页插件 -->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper</artifactId>
<version>5.0.4</version>
</dependency>
</dependencies>

<!-- Package as an executable jar -->
<build>
<finalName>springboot-mybatis</finalName>
<plugins>
<plugin>

<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<testFailureIgnore>true</testFailureIgnore>
</configuration>
</plugin>
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.3.2</version>
<configuration>
<verbose>true</verbose>
<overwrite>true</overwrite>
</configuration>
</plugin>
</plugins>
</build>

</project>

2. 逆向所需配置文件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:\lib\mysql_driver\mysql-connector-java-5.1.26-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/user" 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.fantj.sbmybatis.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.fantj.sbmybatis.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>

3. 利用IDE创建逆向工程启动类



4. add一个Maven configuration





5. 我的数据库和表结构



6. application配置文件

server:
port: 8080

spring:
datasource:
name: test
url: jdbc:mysql://127.0.0.1:3306/user
username: root
password: root
# druid 连接池
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

mybatis:
mapper-locations: classpath:mapping/*.xml
type-aliases-package: com.fant.model

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

运行generator工程 自动生成代码

生成的文件

User.java

package com.fantj.model;

import java.util.Date;

public class User {
private Integer id;

private String username;

private Date birthday;

private String sex;

private String address;

public Integer getId() {
return id;
}

public void setId(Integer id) {
this.id = id;
}

public String getUsername() {
return username;
}

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

public Date getBirthday() {
return birthday;
}

public void setBirthday(Date birthday) {
this.birthday = birthday;
}

public String getSex() {
return sex;
}

public void setSex(String sex) {
this.sex = sex == null ? null : sex.trim();
}

public String getAddress() {
return address;
}

public void setAddress(String address) {
this.address = address == null ? null : address.trim();
}
}

UserMapper .java

package com.fantj.mapper;

import com.fantj.model.User;

import java.util.List;

public interface UserMapper {
int deleteByPrimaryKey(Integer id);

int insert(User record);

int insertSelective(User record);

User selectByPrimaryKey(Integer id);

int updateByPrimaryKeySelective(User record);

int updateByPrimaryKey(User record);

List<User> selectAll();
}

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.fantj.mapper.UserMapper" >
<resultMap id="BaseResultMap" type="com.fantj.model.User" >
<id column="id" property="id" jdbcType="INTEGER" />
<result column="username" property="username" jdbcType="VARCHAR" />
<result column="birthday" property="birthday" jdbcType="DATE" />
<result column="sex" property="sex" jdbcType="CHAR" />
<result column="address" property="address" jdbcType="VARCHAR" />
</resultMap>
<sql id="Base_Column_List" >
id, username, birthday, sex, address
</sql>
<select id="selectAll" resultMap="BaseResultMap" >
select
<include refid="Base_Column_List" />
from user
</select>
<select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
select
<include refid="Base_Column_List" />
from user
where id = #{id,jdbcType=INTEGER}
</select>
<delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
delete from user
where id = #{id,jdbcType=INTEGER}
</delete>
<insert id="insert" parameterType="com.fantj.model.User" >
insert into user (id, username, birthday,
sex, address)
values (#{id,jdbcType=INTEGER}, #{username,jdbcType=VARCHAR}, #{birthday,jdbcType=DATE},
#{sex,jdbcType=CHAR}, #{address,jdbcType=VARCHAR})
</insert>
<insert id="insertSelective" parameterType="com.fantj.model.User" >
insert into user
<trim prefix="(" suffix=")" suffixOverrides="," >
<if test="id != null" >
id,
</if>
<if test="username != null" >
username,
</if>
<if test="birthday != null" >
birthday,
</if>
<if test="sex != null" >
sex,
</if>
<if test="address != null" >
address,
</if>
</trim>
<trim prefix="values (" suffix=")" suffixOverrides="," >
<if test="id != null" >
#{id,jdbcType=INTEGER},
</if>
<if test="username != null" >
#{username,jdbcType=VARCHAR},
</if>
<if test="birthday != null" >
#{birthday,jdbcType=DATE},
</if>
<if test="sex != null" >
#{sex,jdbcType=CHAR},
</if>
<if test="address != null" >
#{address,jdbcType=VARCHAR},
</if>
</trim>
</insert>
<update id="updateByPrimaryKeySelective" parameterType="com.fantj.model.User" >
update user
<set >
<if test="username != null" >
username = #{username,jdbcType=VARCHAR},
</if>
<if test="birthday != null" >
birthday = #{birthday,jdbcType=DATE},
</if>
<if test="sex != null" >
sex = #{sex,jdbcType=CHAR},
</if>
<if test="address != null" >
address = #{address,jdbcType=VARCHAR},
</if>
</set>
where id = #{id,jdbcType=INTEGER}
</update>
<update id="updateByPrimaryKey" parameterType="com.fantj.model.User" >
update user
set username = #{username,jdbcType=VARCHAR},
birthday = #{birthday,jdbcType=DATE},
sex = #{sex,jdbcType=CHAR},
address = #{address,jdbcType=VARCHAR}
where id = #{id,jdbcType=INTEGER}
</update>
</mapper>

修改启动类

逆向生成代码后，我们还需要在启动类上添加一个

@MapperScan("com.fantj.mapper")

注解，告诉我们的Mapper需要扫描的包，这样就不用每个Mapper上都添加@Mapper注解了。

package com.fantj;

import com.fantj.util.Params;
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.Configuration;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@SpringBootApplication
@MapperScan("com.fantj.mapper")
public class MybatisApplication {

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

}

完善controller和service

UserController.java

package com.fantj.controller;

import com.fantj.model.User;
import com.fantj.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import javax.jws.soap.SOAPBinding;
import java.util.Date;
import java.util.List;

@RestController
@RequestMapping("/user")
public class UserController {

@Autowired
private UserService userService;

@RequestMapping(method = RequestMethod.GET,value = "/delete/{id}")
public void delete(@PathVariable("id")int id){
userService.delete(id);
}

@RequestMapping(method = RequestMethod.POST,value = "/insert")
public void insert(User user){
userService.insert(user);
}
@RequestMapping(method = RequestMethod.POST,value = "/update/{id}")
public void update(@RequestParam User user){
userService.update(user);
}

@RequestMapping(method = RequestMethod.GET,value = "/{id}/select")
public User select(@PathVariable("id")int id){
return userService.selectById(id);
}

@RequestMapping(method = RequestMethod.GET,value = "/selectAll/{pageNum}/{pageSize}")
public List<User> selectAll(@PathVariable("pageNum") int pageNum, @PathVariable("pageSize") int pageSize){
return userService.selectAll(pageNum,pageSize);
}

}

UserService.java

package com.fantj.service;

import com.fantj.model.User;

import java.util.List;

public interface UserService {
/** 删除 */
public void delete(int id);
/** 增加*/
public void insert(User user);
/** 更新*/
public int update(User user);
/** 查询单个*/
public User selectById(int id);
/** 查询全部列表*/
public List<User> selectAll(int pageNum, int pageSize);
}

UserServiceImpl .java

package com.fantj.service.impl;

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

import java.util.List;

@Service
public class UserServiceImpl implements UserService {

@Autowired
private UserMapper userMapper;

/**
* 删除
*
* @param id
*/
@Override
public void delete(int id) {
userMapper.deleteByPrimaryKey(id);
}

/**
* 增加
*
* @param user
*/
@Override
public void insert(User user) {
userMapper.insert(user);
}

/**
* 更新
*
* @param user
*/
@Override
public int update(User user) {
return userMapper.updateByPrimaryKey(user);
}

/**
* 查询单个
*
* @param id
*/
@Override
public User selectById(int id) {
return userMapper.selectByPrimaryKey(id);
}

/**
* 查询全部列表,并做分页
*
* @param pageNum 开始页数
* @param pageSize 每页显示的数据条数
*/
@Override
public List<User> selectAll(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.selectAll();
}
}

浏览器访问127.0.0.1/user/selectAll/0/1



说明我们成功了。

一个小甜点

有人问，get方法可以直接从浏览器地址中的url来测试，那post请求怎么测试呢？

个人建议用postman工具，也可以写测试类用代码来完成测试。也可以使用idea的一个测试工具Test RESTful Web Service

注解方式

好了，配置方式我们介绍完了，我在这里稍微聊一聊注解开发方式，个人建议如果想用注解开发，直接用jpa，可以更方便自己的开发。

mybatis java api ：http://www.mybatis.org/mybatis-3/zh/java-api.html

UserMapper.java

package com.fantj.mapper;

import com.fantj.model.User;
import org.apache.ibatis.annotations.*;

import java.util.List;

public interface UserMapper {
/*int deleteByPrimaryKey(Integer id);

int insert(User record);

int insertSelective(User record);

User selectByPrimaryKey(Integer id);

int updateByPrimaryKeySelective(User record);

int updateByPrimaryKey(User record);

List<User> selectAll();*/
//如果实例对象中的属性名和数据表中字段名不一致，用@Result注解进行说明映射关系，我在这里只是告诉你怎么写
@Select("SELECT * FROM user")
@Results({
@Result(property = "username", column = "username"),
@Result(property = "sex",  column = "sex"),
@Result(property = "address",column = "address")
})
List<User> selectAll();

@Select("SELECT * FROM user WHERE id = #{id}")
@Results({
@Result(property = "sex",  column = "sex"),
@Result(property = "username", column = "username")
})
User selectByPrimaryKey(int id);

@Insert({"INSERT INTO user(username,birthday,sex,address}) VALUES(#{userName}, #{birthday}, #{sex},#{address})"})
void insert(User user);

@Update("UPDATE user SET userName=#{userName} WHERE id =#{id}")
int updateByPrimaryKey(User user);

@Delete("DELETE FROM user WHERE id =#{id}")
int deleteByPrimaryKey(int id);
}

注解的一些解释

@Select 是查询类的注解，所有的查询均使用这个

@Result 修饰返回的结果集，关联实体类属性和数据库字段一一对应，如果实体类* 属性和数据库属性名保持一致，就不需要这个属性来修饰。

@Insert 插入数据库使用，直接传入实体类会自动解析属性到对应的值

@Update 负责修改，也可以直接传入对象

@delete 负责删除

注意将application配置文件中的mybatis.mapper-locations:属性注视掉再启动项目。否则它会报错：Mapped Statements collection already contains value for com.fantj.mapper.UserMapper.insert 。意思是mapper中方法重复。

最后一个甜点

还有一个东西忘说了 -.-,就是用cmd来逆向生成代码。



声称语句

java -jar mybatis-generator-core-1.3.2.jar -configfile generator.xml -overwrite

src目录请忽略，这是生成的目录。

好了 干货都分享了，谢谢大家。0.0