Spring Boot使用配置文件方式整合MyBatis

Posted 2021-03-23 红尘年少

pom.xml

 

<?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>2.2.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.uos</groupId>
    <artifactId>databases</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>databases</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-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </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>
        <!--mysql依赖-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.13</version>
        </dependency>
        <!--mybatis依赖-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.1</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>


    </dependencies>

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

</project>

pom.xml

 

项目结构

 

 

一、创建Mapper接口文件

ArticleMapper接口

package com.uos.databases.dao;


import com.uos.databases.domain.Article;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface ArticleMapper {
    public Article selectArticle(Integer id);
    public int updateArticle(Article article);
}

实体类

package com.uos.databases.domain;

/**
 * 评论实体类
 */
public class Comment {
    private Integer id;
    private String content;
    private String author;
    private Integer aId;

    @Override
    public String toString() {
        return "Comment{" +
                "id=" + id +
                ", content=\'" + content + \'\\\'\' +
                ", author=\'" + author + \'\\\'\' +
                ", aId=" + aId +
                \'}\';
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public Integer getaId() {
        return aId;
    }

    public void setaId(Integer aId) {
        this.aId = aId;
    }
}

Comment

package com.uos.databases.domain;

import java.util.List;

/**
 * 文章类
 */
public class Article {
    private Integer id;
    private String title;
    private String content;
    private List<Comment> commentList;

    @Override
    public String toString() {
        return "Article{" +
                "id=" + id +
                ", title=\'" + title + \'\\\'\' +
                ", content=\'" + content + \'\\\'\' +
                ", commentList=" + commentList +
                \'}\';
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }

    public List<Comment> getCommentList() {
        return commentList;
    }

    public void setCommentList(List<Comment> commentList) {
        this.commentList = commentList;
    }
}

Article

 

二、创建xml映射文件：编写对应的SQL语句

<?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.uos.databases.dao.ArticleMapper">
    <select id="selectArticle" resultMap="articleWithComment">
        SELECT a.*,c.id c_id,c.content c_content,c.author
        FROM t_article a,t_comment c
        WHERE a.id=c.a_id AND a.id = #{id}
    </select>

    <update id="updateArticle" parameterType="Article" >
        UPDATE t_article
        <set>
            <if test="title !=null and title !=\'\'">
                title=#{title},
            </if>
            <if test="content !=null and content !=\'\'">
                content=#{content}
            </if>
        </set>
        WHERE id=#{id}
    </update>

    <resultMap id="articleWithComment" type="Article">
        <id property="id" column="id" />
        <result property="title" column="title" />
        <result property="content" column="content" />
        <collection property="commentList" ofType="Comment">
            <id property="id" column="c_id" />
            <result property="content" column="c_content" />
            <result property="author" column="author" />
        </collection>
    </resultMap>

</mapper>

 

三、在全局文件中配置xml映射文件以及实体类别名映射路径

application.properties

spring.datasource.url=jdbc:mysql://192.168.152.120:3306/springbootdata?serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=1

spring.datasource.type = com.alibaba.druid.pool.DruidDataSource
spring.datasource.initialSize=20
spring.datasource.minIdle=10
spring.datasource.maxActive=100
        
#配置MyBatis的xml配置文件路径
mybatis.mapper-locations=classpath:mapper/*.xml
#配置XML映射文件中指定的实体类别名路径
mybatis.type-aliases-package=com.uos.databases.domain

四、编写测试方法进行接口方法测试及整合测试

package com.uos;

import com.uos.databases.dao.ArticleMapper;
import com.uos.databases.domain.Article;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

@SpringBootTest
class DatabasesApplicationTests {
    @Autowired
    private ArticleMapper articleMapper;
    @Test
    public void selectArticle() {
        Article article = articleMapper.selectArticle(1);
        System.out.println(article);
    }

    @Test
    void contextLoads() {
    }

}