spring boot——spring boot的基本配置——spring boot整合mybatis——本地实例运行——保存操作——void类型

pom文件保持不变：

<?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>org.example</groupId>
    <artifactId>spring_boot</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.4.5</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <dependencies>
        <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>2.1.1</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
    </dependencies>
</project>

mapper文件：

<?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="org.example.mapper.UserMapper">
    <select id="findAll" resultType="org.example.entity.MyUser">
        select * from users
    </select>

    <insert id="saveUser" parameterType="org.example.entity.MyUser">
        insert into users(id,name,age) values(#{id},#{name},#{age})
    </insert>

</mapper>

mapper接口：

package org.example.mapper;

import org.example.entity.MyUser;
import org.apache.ibatis.annotations.Mapper;

import java.util.List;

@Mapper
public interface UserMapper
{

    public List<MyUser> findAll();

    void saveUser(MyUser user);

}

dao接口：

package org.example.service;


import org.example.entity.MyUser;

import java.util.List;

public interface UserService
{
    List<MyUser> findAll();

    void saveUser(MyUser user);


}

实现dao接口：

package org.example.service.Impl;


import org.example.entity.MyUser;
import org.example.mapper.UserMapper;
import org.example.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

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

    @Override
    public List<MyUser> findAll()
    {

        return userMapper.findAll();
    }

    @Override
    public void saveUser(MyUser user)
    {

        userMapper.saveUser(user);


    }
}

控制器：

package org.example.controller;

import java.util.List;
import org.example.entity.MyUser;
import org.example.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class MyUserController
{
    @Autowired
    private UserService userService;

    @GetMapping(value = "/1")
    public List<MyUser> home1()
    {
        // 查询所有网站
        List<MyUser> users = userService.findAll();

        for (MyUser user : users)
        {
            System.out.println(user.getId()+"  "+user.getName()+"  "+user.getAge());
        }

        return users;
    }

    @GetMapping(value = "/2")
    public void home2()
    {
        MyUser user2 = new MyUser();
        user2.setName("ttt");
        user2.setAge(25198);

        userService.saveUser(user2);

    }


}