springboot集成mybatis

springboot集成mybatis

实现步骤：

1.准备数据库创建表
2.添加起步依赖
3.创建POJO
4.创建mapper接口
5.创建映射文件
6.配置yml 指定映射文件位置
7.创建启动类，加入注解扫描
8.创建service controller 进行测试

1.创建数据库表

-- ----------------------------
-- Table structure for `user`
-- ----------------------------
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`username` varchar(50) DEFAULT NULL,
`password` varchar(50) DEFAULT NULL,
`name` varchar(50) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of user
-- ----------------------------
INSERT INTO `user` VALUES ('1', 'zhangsan', '123', '张三');
INSERT INTO `user` VALUES ('2', 'lisi', '123', '李四');

2.创建工程并添加依赖pom.xml如下参考

<?xml version="1.0" encoding="UTF-8"?>
         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">
    4.0.0
?
    com.guigu
    guigu-springboot-mybatis-demo04
    1.0-SNAPSHOT
?
    
        org.springframework.boot
        spring-boot-starter-parent
        2.1.4.RELEASE
    
?
    
        
        
            mysql
            mysql-connector-java
            runtime
        
        
        
            org.mybatis.spring.boot
            mybatis-spring-boot-starter
            2.0.1
        
        
        
            org.springframework.boot
            spring-boot-starter-web
        
?
    
?
    
        
            
                org.springframework.boot
                spring-boot-maven-plugin
            
        
    
?
?

3.创建pojo

public class User implements Serializable{
    private Integer id;
    private String username;//用户名
    private String password;//密码
    private String name;//姓名
    //getter setter...
    //toString
}

4.创建mapper接口

package com.guigu.dao;
?
import com.guigu.pojo.User;
?
import java.util.List;
?
/***
 * mapper接口
 * @author javaboy
 * @packagename com.guigu.dao
 * @version 1.0
 * @date 2020/2/23
 */
public interface UserMapper {
    public List findAllUser();
}

5.创建UserMapper映射文件，如下图所示

 
?
<?xml version="1.0" encoding="UTF-8" ?>


    
        SELECT * from user
    

xml文件放Resource中的mappers文件下

6.创建配置application.yml文件：

spring:
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost/springboot_user?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC
    username: root
    password: 123456
#配置mapper的映射文件的位置
mybatis:
  mapper-locations: classpath:mappers/*Mapper.xml

7.创建启动类，加入mapper接口注解扫描

 
?
@SpringBootApplication
@MapperScan(basePackages = "com.guigu.dao")
//MapperScan 用于扫描指定包下的所有的接口，将接口产生代理对象交给spriing容器
public class MybatisApplication {
    public static void main(String[] args) {
        SpringApplication.run(MybatisApplication.class,args);
    }
}

8.创建service 实现类和接口

package com.guigu.service.impl;
?
import com.guigu.dao.UserMapper;
import com.guigu.pojo.User;
import com.guigu.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
?
import java.util.List;
?
/***
 * 描述
 * @author javaboy
 * @packagename com.guigu.service.impl
 * @version 1.0
 * @date 2020/2/23
 */
@Service
public class UserServiceImpl implements UserService {
?
    @Autowired
    private UserMapper userMapper;
?
    @Override
    public List findAllUser() {
        return userMapper.findAllUser();
    }
}

接口如下：

package com.guigu.service.impl;
?
import com.guigu.dao.UserMapper;
import com.guigu.pojo.User;
import com.guigu.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
?
import java.util.List;
?
/***
 * 描述
 * @author javaboy
 * @packagename com.guigu.service.impl
 * @version 1.0
 * @date 2020/2/23
 */
@Service
public class UserServiceImpl implements UserService {
?
    @Autowired
    private UserMapper userMapper;
?
    @Override
    public List findAllUser() {
        return userMapper.findAllUser();
    }
}

9.创建controller

package com.guigu.controller;
?
import com.guigu.pojo.User;
import com.guigu.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
?
import java.util.List;
?
/***
 * 描述
 * @author javaboy
 * @packagename com.guigu.controller
 * @version 1.0
 * @date 2020/2/23
 */
@RestController
@RequestMapping("/user")
public class UserController {
?
    @Autowired
    private UserService userService;
?
    @RequestMapping("/findAll")
    public List findAll(){
        return userService.findAllUser();
    }
}

10.测试

浏览器中发送请求：http://localhost:8080/user/findAll