Spring Boot学习(九)之Spring Boot整合MyBatis

柔光的暖阳◎ 2022-06-02 01:00 193阅读 0赞

**前言**

现在业界比较流行的数据操作层框架 MyBatis，下面就讲解下 Springboot 如何整合 MyBatis，这里使用的是注解配置SQL.

Spring中整合MyBatis就不多说了，最近大量使用Spring Boot，因此整理一下Spring Boot中整合MyBatis的步骤。搜了一下Spring Boot整合MyBatis的文章，方法都比较老，比较繁琐。查了一下文档，实际已经支持较为简单的整合与使用。下面就来详细介绍如何在Spring Boot中整合MyBatis，并通过注解方式实现映射。

**整合MyBatis**

新建Spring Boot项目

**pom.xml**中引入依赖

*  这里用到spring-boot-starter基础和spring-boot-starter-test用来做单元测试验证数据访问
 *  引入连接mysql的必要依赖mysql-connector-java
 *  引入整合MyBatis的核心依赖mybatis-spring-boot-starter
 *  这里不引入spring-boot-starter-jdbc依赖，是由于mybatis-spring-boot-starter中已经包含了此依赖

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
       <modelVersion>4.0.0</modelVersion>
    
       <groupId>com.xiaojingg</groupId>
       <artifactId>springbootstudy-demo9-mybatis</artifactId>
       <version>0.0.1-SNAPSHOT</version>
       <packaging>jar</packaging>
    
       <name>springbootstudy-demo9-mybatis</name>
       <description>Demo project for Spring Boot</description>
    
       <parent>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-parent</artifactId>
          <version>1.5.9.RELEASE</version>
          <relativePath/> 
       </parent>
    
       <properties>
          <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
          <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
          <java.version>1.8</java.version>
       </properties>
    
       <dependencies>
    
          <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter</artifactId>
          </dependency>
    
          <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
             <scope>test</scope>
          </dependency>
    
          <dependency>
             <groupId>org.mybatis.spring.boot</groupId>
             <artifactId>mybatis-spring-boot-starter</artifactId>
             <version>1.1.1</version>
          </dependency>
    
          <dependency>
             <groupId>mysql</groupId>
             <artifactId>mysql-connector-java</artifactId>
             <version>5.1.21</version>
          </dependency>
    
       </dependencies>
    
       <build>
          <plugins>
             <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
             </plugin>
          </plugins>
       </build>
    </project>

同之前介绍的使用jdbc和spring-data连接数据库一样，在application.properties中配置mysql的连接配置

**spring.datasource.url**=**jdbc:mysql://localhost:3306/test**

**spring.datasource.username**=**root**

**spring.datasource.password**=**root**

**spring.datasource.driver-class-name**=**com.mysql.jdbc.Driver**

同其他Spring Boot工程一样，简单且简洁的的完成了基本配置，下面看看如何在这个基础下轻松方便的使用MyBatis访问数据库。

**使用MyBatis**

*  在Mysql中创建User表，包含id(BIGINT)、name(INT)、age(VARCHAR)字段。同时，创建映射对象User

package com.xiaojingg.domain;
    
    public class User {
    
        private Long id;
        private String name;
        private Integer age;
    
        public Long getId() {
            return id;
        }
    
        public void setId(Long id) {
            this.id = id;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public Integer getAge() {
            return age;
        }
    
        public void setAge(Integer age) {
            this.age = age;
        }
    
    }

*  创建User映射的操作UserMapper，为了后续单元测试验证，实现插入和查询操作

package com.xiaojingg.domain;
    
    import org.apache.ibatis.annotations.*;
    
    @Mapper
    public interface UserMapper {
    
        @Select("SELECT * FROM USER WHERE NAME = #{name}")
        User findByName(@Param("name") String name);
    
        @Insert("INSERT INTO USER(NAME, AGE) VALUES(#{name}, #{age})")
        int insert(@Param("name") String name, @Param("age") Integer age);
    
    }
    主类如下:
    package com.xiaojingg;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class SpringbootstudyDemo9MybatisApplication {
    
       public static void main(String[] args) {
          SpringApplication.run(SpringbootstudyDemo9MybatisApplication.class, args);
       }
    }
    创建单元测试
    测试逻辑：插入一条name=AAA，age=20的记录，然后根据name=AAA查询，打印数据
    测试结束回滚数据，保证测试单元每次运行的数据环境独立,这里可以屏蔽这里注解!
    package com.xiaojingg;
    
    import com.xiaojingg.domain.User;
    import com.xiaojingg.domain.UserMapper;
    import org.junit.Assert;
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.test.annotation.Rollback;
    import org.springframework.test.context.junit4.SpringRunner;
    import org.springframework.transaction.annotation.Transactional;
    
    @RunWith(SpringRunner.class)
    @SpringBootTest
    //@Transactional
    public class SpringbootstudyDemo9MybatisApplicationTests {
       @Autowired
       private UserMapper userMapper;
       @Test
       @Rollback
       public void findByName() throws Exception {
          userMapper.insert("AAA", 20);
          User u = userMapper.findByName("AAA");
          System.out.print("========================="+u.getAge().intValue());
       }
    }

运行截图如下:

![20171228161152747][]

![20171228161204847][]

[20171228161152747]: /images/20220602/0a03e35745104f4b8fa4f4cd5b617eb4.png
[20171228161204847]: /images/20220602/dbdcf594cda64ce68c63b710a8bf3579.png