springboot2.2和mybatis2.1的增删改查

直接结构图

数据表

CREATE TABLE `user` (
`id` int(32) NOT NULL AUTO_INCREMENT,
`user_name` varchar(32) NOT NULL,
`pass_word` varchar(50) NOT NULL,
`real_name` varchar(32) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

CREATE TABLE `t_userinfo` (
`ID` int(11) unsigned NOT NULL AUTO_INCREMENT,
`UserName` varchar(50) DEFAULT NULL,
`PassWord` varchar(50) DEFAULT NULL,
PRIMARY KEY (`ID`)
) ENGINE=InnoDB  AUTO_INCREMENT=4 DEFAULT CHARSET=utf8

pom.xm文件内容

<?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 https://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>2.2.5.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com</groupId>
	<artifactId>example</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>LinMyBatis</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-web-services</artifactId>
		</dependency>
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
		</dependency>
		<dependency>
			<groupId>org.mybatis.spring.boot</groupId>
			<artifactId>mybatis-spring-boot-starter</artifactId>
			<version>2.1.1</version>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
			<exclusions>
				<exclusion>
					<groupId>org.junit.vintage</groupId>
					<artifactId>junit-vintage-engine</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

配置数据库

src/main/resources/application.properties

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=

mybatis.mapper-locations=classpath:mapping/*Mapper.xml
mybatis.type-aliases-package=com.example.entity

　　

1.编写实体代码

       src/main/java/com/example/entity/User.java

package com.example.entity;


public class User
{
	private Integer id;
	private String userName;
	private String passWord;
	private String realName;
	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;
	}
	public String getPassWord() {
		return passWord;
	}
	public void setPassWord(String passWord) {
		this.passWord = passWord;
	}
	public String getRealName() {
		return realName;
	}
	public void setRealName(String realName) {
		this.realName = realName;
	}
	
	public String toString()
	{
		return "User:{id="+id+",userName="+userName+",passWord="+passWord+",realName="+realName+"}";
	}
}

　　2.编写请求的控制器名

src/main/java/com/example/controller/UserController.java

package com.example.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import com.example.entity.User;
import com.example.service.UserService;

@RestController
@RequestMapping("/user")
public class UserController
{
	@Autowired
	private UserService userService;
	/**
	 * 查找单一记录
	 * @param id
	 * @return
	 */
	@RequestMapping("findOne/{id}")
	public String findOne(@PathVariable int id)
	{
		return userService.findOne(id).toString();
	}
	
	@RequestMapping("getDataMultiTable/{id}")
	public List<Object> getDataMultiTable(@PathVariable int id)
	{
		return userService.getDataMultiTable(id);
	}
	
	/**
	 * 查找所有
	 * @return
	 */
	@RequestMapping("findAll")
	public List<User> findAll()
	{
		return userService.findAll();
	}
	
	/**
	 * 增加数据
	 * @param args
	 * @return
	 */
	@RequestMapping(value="addData",method = RequestMethod.POST)
	public int addData(@RequestBody User args)
	{
		User user = new User();
		user.setUserName(args.getUserName());
		user.setPassWord(args.getPassWord());
		user.setRealName(args.getRealName());
		System.out.println(args);
		return userService.addData(user);
	}
	
	/**
	 * 删除指定记录
	 * @param id
	 * @return
	 */
	@RequestMapping("deleteUser/{id}")
	public int deleteUser(@PathVariable int id)
	{
		return userService.deleteData(id);
	}
	
	/**
	 * 更新数据
	 * @param args
	 * @return
	 */
	@RequestMapping(value="updateData",method=RequestMethod.POST)
	public int updateData(@RequestBody User args)
	{
		User user = new User();
		user.setId(args.getId());
		user.setRealName(args.getRealName());
		return userService.updateData(user);
	}
	
	
}

　　3.编写请求的服务

package com.example.service;

import java.util.List;

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

import com.example.entity.User;
import com.example.mapper.UserMapper;

@Service
public class UserService
{
	@Autowired
	UserMapper userMapper;
	public User findOne(int id)
	{
		return userMapper.findOne(id);
	}
	
	public List<User> findAll()
	{
		return userMapper.findAll();
	}
	
	public int deleteData(int id)
	{
		return userMapper.deleteData(id);
	}
	
	public int addData(User user)
	{
		return userMapper.addData(user);
	}
	
	public int updateData(User user)
	{
		return userMapper.updateData(user);
	}
	
	public List<Object> getDataMultiTable(int id)
	{
		return userMapper.getDataMultiTable(id);
	}
}

　　4.服务映射

src/main/java/com/example/mapper/UserMapper.java

package com.example.mapper;

import java.util.List;

import org.springframework.stereotype.Repository;

import com.example.entity.User;

@Repository
public interface UserMapper
{
	User findOne(int id);
	
	List<User> findAll();
	
	int deleteData(int id);
	
	int addData(User user);
	
	int updateData(User user);
	
	List<Object> getDataMultiTable(int id);
}

　　5.编写增删改查

src/main/resources/mapping/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.example.mapper.UserMapper">
	<resultMap id="BaseResultMap" type="com.example.entity.User">
		<result column="id" jdbcType="INTEGER" property="id" />
		<result column="user_name" jdbcType="VARCHAR" property="userName" />
		<result column="pass_word" jdbcType="VARCHAR" property="passWord" />
		<result column="real_name" jdbcType="VARCHAR" property="realName" />
	</resultMap>
	
	<select id="findOne" resultType="com.example.entity.User">
		select * from user where id = #{id}
	</select>
	
	<select id="findAll" resultType="hashmap">
	select * from user
	</select>	
	

	<select id="getDataMultiTable" resultType="hashmap">
	select u.*,tu.id as tu_id,tu.UserName as tu_username 
	from user as u join t_userinfo as tu on u.id = tu.id 
	where u.id > #{id} limit 1
	</select>
	
	<insert id="addData" keyColumn="id" useGeneratedKeys="true" keyProperty="id"  parameterType="User">
	 insert into user (user_name,pass_word,real_name) values (#{userName},#{passWord},#{realName})
	</insert>
	
	<delete id="deleteData">
	delete from user where id = #{id}
	</delete>
	
	<update id="updateData" keyColumn="id" useGeneratedKeys="true" keyProperty="id"  parameterType="User">
	update user set real_name=#{realName} where id = #{id}
	</update> 
</mapper>

　　请求结果如下

1.获取所有数据

删除指定数据

修改指定的数据

新增数据

参考文档与代码

https://www.w3cschool.cn/mybatis/f4uw1ilx.html

https://blog.csdn.net/iku5200/article/details/82856621

https://blog.mybatis.org/