spring-boos中引入mybatis示例

朱雀 2021-05-12 11:55 367阅读 0赞

上一篇文章介绍了如何使用spring-boot搭建一个简单的web应用。这篇重点介绍如何把mybatis引入到其中。

1、pom.xml中引入：

<properties>
        <mybatis-spring-boot>1.2.0</mybatis-spring-boot>
        <mysql-connector>5.1.39</mysql-connector>
      </properties>
    
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>${mybatis-spring-boot}</version>
        </dependency>
        
         
         <dependency>
             <groupId>mysql</groupId>
             <artifactId>mysql-connector-java</artifactId>
             <version>${mysql-connector}</version>
         </dependency>

整个工程结构如下图

![20180523204856441][]

2、entity实体类：

public class Test {
    	private Long id;
    	private String name;
    	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;
    	}
    }

3、dao接口：

public interface TestDao {
    	/**
         * 根据名称，查询test信息
         *
         * @param name 名
         */
        Test findByName(@Param("name") String n);
    }

Mybatis是基于接口编程的，我们写好接口，对应编写映射文件中的sql语句即可，非常灵活。

4、mapper.xml文件：

在resources文件夹下新建一个mapper文件夹，里面存放mybatis的mapper XML映射文件。

<?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="nc.edu.nuc.dao.mysql.TestDao">  
        <resultMap id="BaseResultMap" type="nc.edu.nuc.entity.Test">  
            <result column="id" property="id" />  
            <result column="name" property="name" />  
        </resultMap>  
      
        <parameterMap id="Test" type="nc.edu.nuc.entity.Test"/>  
      
        <sql id="Base_Column_List">  
            id,name  
        </sql>  
      
        <select id="findList" resultMap="BaseResultMap">  
            select  
            <include refid="Base_Column_List" />  
            from test  
        </select>  
      
        <select id="findByName" resultMap="BaseResultMap" parameterType="java.lang.String">  
            select  
            <include refid="Base_Column_List" />  
            from test  
            where name = #{name}  
        </select>  
          
        <insert id="save" parameterType="Test">  
            insert into test   
            (name)   
            values   
            (#{name})  
        </insert>  
          
    </mapper>

5、service类：

@Service
    public class TestService{
    	
    	@Autowired  
    	private TestDao testDao;  
    	
    	public Test findByName(String name) {
    		return testDao.findByName(name);
    	}
    	
    	
    }

6、controller接口：

@Controller
    public class TestController {
    	
    	@Autowired
    	private TestService testService;
    	
    	@RequestMapping("test")
        @ResponseBody
        public String home(HttpServletRequest request) {
    		String name = request.getParameter("name");
    		Test findByName = testService.findByName(name);
            return findByName.toString();
        }
    
    }

7、启动类：

@SpringBootApplication
    //mapper 接口类扫描包配置
    @MapperScan("nc.edu.nuc.dao.mysql")
    public class App 
    {
        public static void main( String[] args )
        {
        	SpringApplication.run(App.class, args);
        }
    }

在启动泪伤添加一个@MapperScan的注解，也可以在每一个Dao类上添加一个@Mapper的注解。

application.properties:

##mysql配置
    spring.datasource.url=jdbc:mysql://jy.ttengine.w.abc.db:1883/ttengine?useUnicode=true&characterEncoding=utf8
    spring.datasource.username=ttengine
    spring.datasource.password=TTengine123
    spring.datasource.driver-class-name=com.mysql.jdbc.Driver
    
    ## Mybatis配置
    mybatis.typeAliasesPackage=cn.edu.nuc.springbootmybatis.entity
    mybatis.mapperLocations=classpath:mapper/*.xml
    
    
    # 页面默认前缀目录
    spring.mvc.view.prefix=/WEB-INF/page/
    spring.mvc.view.suffix=.jsp

参考：https://github.com/JeffLi1993/springboot-learning-example

[20180523204856441]: /images/20210511/6b9e959d5b3e4116ac36d973473c21c6.png