SpringBoot 集成 Mybatis

用 Interllij IDEA 创建项目就不贴了

1. 添加相关依赖

pom 文件中依赖

<?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>2.4.4</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</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-data-jdbc</artifactId>
        </dependency>
        <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>2.1.4</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.29</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory><!--所在的目录-->
                <includes><!--包括目录下的.properties,.xml文件都会扫描到-->
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <!--包含所在的目录的资源-->
                    <executable>true</executable>
                </configuration>
            </plugin>
        </plugins>


    </build>

</project>

2. 编写 mapper

LoginMapper

@Mapper
public interface LoginMapper {
    @Select("SELECT * FROM user WHERE id = #{id}")
    User selectUser(int id);

    User selectUserOnly(Long id);
}

LoginMapper.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.demo.mapper.LoginMapper">

    <select id="selectUserOnly" parameterType="Long" resultType="com.example.demo.bean.User">
        SELECT * FROM user WHERE id = #{id}
    </select>

</mapper>

3. 编写 Controller

@RestController
public class UserControl {

    @Autowired
    LoginMapper loginMapper;

    @RequestMapping(value = "/user", method = RequestMethod.GET)
    public User addNewArticle(@RequestParam(value = "user_id", defaultValue = "1")Integer id) {
        User user = loginMapper.selectUser(id);
        return user;
    }

    @RequestMapping(value = "/user_only", method = RequestMethod.GET)
    public User selectUserOnly(@RequestParam(value = "user_id", defaultValue = "1")Long id) {
        User user = loginMapper.selectUserOnly(id);
        return user;
    }
}

4. 配置文件
   application.properties

spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
#spring.datasource.url=jdbc:mysql://120.79.214.74/vueblog2?useUnicode=true&characterEncoding=UTF-8
spring.datasource.url=jdbc:mysql:///vueblog2?useUnicode=true&characterEncoding=UTF-8
spring.datasource.username=root
spring.datasource.password=123456
mybatis.config-location=classpath:/mybatis-config.xml
#jdbc:mysql://localhost:3306/heima
server.port=8088
logging.level.org.springframework.security=info

5. 文件目录

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