SpringBoot整合Mybatis-方式2：mapper使用XML配置方式

上一篇博文已经详细介绍了SpringBoot环境搭建过程，这一节介绍一下SpringBoot整合Mybatis，在mapper中数据库的查询操作使用的是注解的方式，本文将介绍使用XML的方式进行整合。

SpringBoot整合Mybatis

方式2：mapper使用XML

项目结构

1：准备数据库数据和配置数据源以及配置Mybatis的XML配置文件

#加载Mybatis配置文件 mybatis.mapper-locations = classpath:mapper/*Mapper.xml mybatis.config-location = classpath:config/sqlMapConfig.xml   #数据源必填项 spring.datasource.driver-class-name= com.mysql.jdbc.Driver spring.datasource.url = jdbc:mysql://localhost:3306/study?useUnicode=true&characterEncoding=utf-8 spring.datasource.username = root spring.datasource.password = 123456   #选填 # Number of ms to wait before throwing an exception if no connection is available. spring.datasource.tomcat.max-wait=10000 # Maximum number of active connections that can be allocated from this pool at the same time. spring.datasource.tomcat.max-active=50 # Validate the connection before borrowing it from the pool. spring.datasource.tomcat.test-on-borrow=true

2：编写Mapper.Xml和sqlMapConfig.xml

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.liujia.springdemo.mapper.UserMapper" >     <select id="getAll" resultType="com.liujia.springdemo.entity.User"  >         SELECT *         FROM user     select> mapper>

sqlMapConfig.xml

xml version="1.0" encoding="UTF-8" ?> DOCTYPE configuration         PUBLIC "-//mybatis.org//DTD Config 3.0//EN"         "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration>      <typeAliases>      typeAliases> configuration>

3：加maven依赖

<dependency>                <groupId>org.mybatis.spring.bootgroupId>                <artifactId>mybatis-spring-boot-starterartifactId>                <version>1.3.2version>           dependency>                     <dependency>                <groupId>mysqlgroupId>                <artifactId>mysql-connector-javaartifactId>           dependency>

4：编写实体类

public class User implements Serializable {        private static final long serialVersionUID = 1L;        private int id;// id        private String name;// 姓名        private int age;// 年龄        public int getId() {           return id;      }        public void setId(int id) {           this.id = id;      }        public String getName() {           return name;      }        public void setName(String name) {           this.name = name;      }        public int getAge() {           return age;      }        public void setAge(int age) {           this.age = age;      }        @Override      public String toString() {           return "User [id=" + id + ", name=" + name + ", age=" + age + "]";      }   }

5：编写mapper

import com.liujia.springdemo.entity.User;   public interface UserMapper {        /**       * 获取所有的user对象       *       * @return       */      List getAll(); }

6：编写service层

import java.util.List;   import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service;   import com.liujia.springdemo.entity.User; import com.liujia.springdemo.mapper.UserMapper;   @Service public class UserService {     @Autowired     private UserMapper userMapper;       public List getAll() {          return userMapper.getAll();     }; }

7：编写Copntroller层

import java.util.List;   import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController;   import com.liujia.springdemo.entity.User; import com.liujia.springdemo.service.UserService;   @RestController public class UserController {        @Autowired      private UserService userService;        @RequestMapping("/getallusers")      public List getAllUsers() {           return userService.getAll();          } }

8：增加包扫描和运行程序

@SpringBootApplication @MapperScan(basePackages = {"com.liujia.springdemo.mapper"}) public class Application {       public static void main(String[] args) {         SpringApplication.run(Application.class, args);     }       @Bean     public CommandLineRunner commandLineRunner(ApplicationContext ctx) {         return args -> {             System.out.println("Let's inspect the beans provided by Spring Boot:");             String[] beanNames = ctx.getBeanDefinitionNames();             Arrays.sort(beanNames);             for (String beanName : beanNames) {                 System.out.println(beanName);             }         };     } }

运行结果

参考文献

https://docs.spring.io/spring-boot/docs/2.0.5.RELEASE/reference/htmlsingle/#boot-features-using-jdbc-template

https://blog.csdn.net/saytime/article/details/74783296

总结：

两种方式的区别

1：是否需要在application.properties中配置mapper.xml和sqlMapperConfig.xml

2：将SQL语句写在了XML中

由于第二种方式将比较繁琐的SQL语句写在了配置文件中，整个代码结构更加清晰，本人更加喜欢此种配置方式。

源码下载地址

https://download.csdn.net/download/caoshangfeidie000/10670735