springboot学习随笔(四):Springboot整合mybatis(含generator自动生成代码)

这章我们将通过springboot整合mybatis来操作数据库

以下内容分为两部分,一部分主要介绍generator自动生成代码,生成model、dao层接口、dao接口对应的sql配置文件

第一部分:

1.修改的pom.xml,最终pom如下,添加了自动生成代码generator插件

<?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>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.20.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>Springboot</name>
<description>Demo project for Spring Boot</description> <properties>
<java.version>1.8</java.version>
</properties> <dependencies>
<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> <!-- 整合mybatis -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.0</version>
</dependency> <dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency> <!-- 分页插件 -->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>1.1.2</version>
</dependency> <!-- druid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>

2.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/mysql_test
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.example.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

3.添加generator配置文件

在src/main/resources目录下,添加generator配置文件,路径:src/main/resources/generator/generatorConfig.xml

generatorConfig.xml如下:

注意:修改部分内容:

1.<classPathEntry  location="E:\devtools\repo\mysql\mysql-connector-java\5.1.24\mysql-connector-java-5.1.24.jar"/>
  修改为实际的mysql-connect的jar包全路径(如果是本地仓库的,就写本地仓库的地址,如上就是我的本地仓库的jar包地址)
2.<jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://127.0.0.1/mysql_test" userId="root" password="root">
  修改为实际数据库ip,数据库名,账号,密码 3.<
javaModelGenerator targetPackage="com.example.model" targetProject="src/main/java">
  targetPackage修改为生成model的包名 4.<javaClientGenerator type="XMLMAPPER" targetPackage="com.example.mapper" targetProject="src/main/java">
  targetPackage修改为生成mapper的包名

<?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:\devtools\repo\mysql\mysql-connector-java\5.1.24\mysql-connector-java-5.1.24.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/mysql_test" 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.example.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.example.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>

4.在数据库中创建user表,

  springboot学习随笔(四):Springboot整合mybatis(含generator自动生成代码)

5.根据表生成model、mapper、sqlmapper

右键项目,run-as,maven-build,下图框中输入:mybatis-generator:generate ,  执行run

springboot学习随笔(四):Springboot整合mybatis(含generator自动生成代码)

6.执行成功后刷新项目,会发现自动生成了model、mapper、mapper.xml(如接着上章的操作,则删除之前的main\User.java),最终目录如下

springboot学习随笔(四):Springboot整合mybatis(含generator自动生成代码)

User.java对应了数据库中的user表

package com.example.model;

import java.io.Serializable;

public class User implements Serializable{
/**
*
*/
private static final long serialVersionUID = 6308154504229603370L; private Long id; private String name; private Integer age; 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 == null ? null : name.trim();
} public Integer getAge() {
return age;
} public void setAge(Integer age) {
this.age = age;
}
}

UserMapper.java 自动生成了dao层的增删改查接口

package com.example.mapper;

import com.example.model.User;

public interface UserMapper {
int deleteByPrimaryKey(Long id); int insert(User record); int insertSelective(User record); User selectByPrimaryKey(Long id); int updateByPrimaryKeySelective(User record); int updateByPrimaryKey(User record);
}

UserMapper.xml则自动生成了UserMapper.java中接口对应的sql

<?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.example.mapper.UserMapper" >
<resultMap id="BaseResultMap" type="com.example.model.User" >
<id column="id" property="id" jdbcType="BIGINT" />
<result column="name" property="name" jdbcType="VARCHAR" />
<result column="age" property="age" jdbcType="INTEGER" />
</resultMap>
<sql id="Base_Column_List" >
id, name, age
</sql>
<select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Long" >
select
<include refid="Base_Column_List" />
from user
where id = #{id,jdbcType=BIGINT}
</select>
<delete id="deleteByPrimaryKey" parameterType="java.lang.Long" >
delete from user
where id = #{id,jdbcType=BIGINT}
</delete>
<insert id="insert" parameterType="com.example.model.User" >
insert into user (id, name, age)
values (#{id,jdbcType=BIGINT}, #{name,jdbcType=VARCHAR}, #{age,jdbcType=INTEGER})
</insert>
<insert id="insertSelective" parameterType="com.example.model.User" >
insert into user
<trim prefix="(" suffix=")" suffixOverrides="," >
<if test="id != null" >
id,
</if>
<if test="name != null" >
name,
</if>
<if test="age != null" >
age,
</if>
</trim>
<trim prefix="values (" suffix=")" suffixOverrides="," >
<if test="id != null" >
#{id,jdbcType=BIGINT},
</if>
<if test="name != null" >
#{name,jdbcType=VARCHAR},
</if>
<if test="age != null" >
#{age,jdbcType=INTEGER},
</if>
</trim>
</insert>
<update id="updateByPrimaryKeySelective" parameterType="com.example.model.User" >
update user
<set >
<if test="name != null" >
name = #{name,jdbcType=VARCHAR},
</if>
<if test="age != null" >
age = #{age,jdbcType=INTEGER},
</if>
</set>
where id = #{id,jdbcType=BIGINT}
</update>
<update id="updateByPrimaryKey" parameterType="com.example.model.User" >
update user
set name = #{name,jdbcType=VARCHAR},
age = #{age,jdbcType=INTEGER}
where id = #{id,jdbcType=BIGINT}
</update>
</mapper>

以上是通过generator自动生成代码。是不是可以少些很多代码呀。。

接下来我们进入第二部分,开始操作数据库

第二部分:

1.修改SpringbootApplication.java启动类,添加mapper扫描包

springboot学习随笔(四):Springboot整合mybatis(含generator自动生成代码)

2.编写通用返回类ResultModel

package com.example.demo.base;

import java.io.Serializable;

public class ResultModel<T> implements Serializable {

    /**
*
*/
private static final long serialVersionUID = -3045412214539024289L;
private String resultCode;
private String resultMsg;
private T t; public String getResultCode() {
return resultCode;
} public void setResultCode(String resultCode) {
this.resultCode = resultCode;
} public String getResultMsg() {
return resultMsg;
} public void setResultMsg(String resultMsg) {
this.resultMsg = resultMsg;
} public T getT() {
return t;
} public void setT(T t) {
this.t = t;
} }

3.编写Service层代码UserService.java(本次直接编写实现,不在分servicce接口和实现)

package com.example.demo.service;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service; import com.example.demo.base.ResultModel;
import com.example.mapper.UserMapper;
import com.example.model.User; @Service
public class UserService { @Autowired
private UserMapper userMapper; public ResultModel<User> insert(User user){
ResultModel<User> rm = new ResultModel<User>();
try {
userMapper.insert(user);
} catch (Exception e) {
rm.setResultCode("9999999");
}
rm.setResultCode("0000000");
rm.setResultMsg("新增成功");
return rm;
}
}

4.修改UserController.java

package com.example.demo.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController; import com.example.demo.base.ResultModel;
import com.example.demo.service.UserService;
import com.example.model.User; @RestController
@RequestMapping("/user")
public class UserController { @Autowired
private UserService userService; @RequestMapping("/add")
public ResultModel<User> user(User user){
ResultModel<User> rm = userService.insert(user);
return rm;
}
}

5.在浏览器中访问,实现添加User

springboot学习随笔(四):Springboot整合mybatis(含generator自动生成代码)

springboot学习随笔(四):Springboot整合mybatis(含generator自动生成代码)

本章内容结束,如有疑问请留言

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