Springboot+mybatis使用xml形式的小demo

• 首先看目錄
  
• 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.mini.program.program.dao.UserDao">

    <resultMap id="findAllUser" type="com.mini.program.program.entity.User">
        <id  property="id" column="id"/>
        <result property="username" column="username"/>
        <result property="password" column="password"/>
    </resultMap>

    <select id="getAllUser"  resultType="User" resultMap="findAllUser">
        SELECT * FROM myuser
    </select>
</mapper>

• application.properties

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/demo?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=123456789

mybatis.mapperLocations=classpath:mapper/*.xml
mybatis.typeAliasesPackage=com.mini.program.program.entity

• 主程序的入口加上@MapperScan("com.mini.program.program.dao")
• dao:
  @Repository public interface UserDao { List<User> getAllUser(); }
• entity

@Data
public class User {
    private  int id;
    private String username;
    private String password;

}

• services

@Service
public class UserServices {

    @Autowired
    UserDao userDao;

    public List<User> getAllUser() {
        return  userDao.getAllUser();

    }
}

• controller

@RestController
public class UserController {
    @Autowired
    UserServices userServices;

    @ResponseBody
    @RequestMapping("/getAllUser")
    public List<User> findAllUser(){
        if (userServices.getAllUser()!= null){
            return userServices.getAllUser();
        }else {
            return null;

        }

    }

}

• 依賴

<?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>2.1.3.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.mini.program</groupId>
	<artifactId>program</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>program</name>
	<description>Demo project for Spring Boot</description>

	<properties>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.mybatis.spring.boot</groupId>
			<artifactId>mybatis-spring-boot-starter</artifactId>
			<version>2.0.0</version>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
			<scope>runtime</scope>
		</dependency>
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<scope>runtime</scope>
		</dependency>
		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
			<optional>true</optional>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
	</dependencies>

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

</project>

• 數據庫
  
• 測試結果
  
  注意事項：我用的lombok,可能不能用，自行百度，我的是能用的，熱部署Devtools