Spring boot+MyBatis编写一个接口的完整思路过程
2019-07-18 本文已影响0人
老陈的记事本
大致步骤, 对应示例为获取一条线索信息
一、建实体类，建立pojo类，对应数据库完整字段；建立vo类，对应视图；
- pojo类示例, @Data 注解帮我们实现了getter和setter，以及toString方法
pojo类对应的数据库完整字段列表
package com.puzzle.api.entity.po;
import lombok.Data;
import java.io.Serializable;
@Data
public class GameClue implements Serializable {
private Integer id;
private Integer clueKey;
private String title;
private String tips;
private String tipsLogo;
private String photo;
private String local;
private String qrcode;
private Integer status;
private Integer cTime;
private Integer uTime;
private Integer del;
}
- vo类示例
通常情况下，vo类比pojo字段要少，只定义返回的字段
vo类可以定义来源多个表的字段
package com.puzzle.api.entity.vo;
import com.puzzle.api.utils.ConstEnv;
import lombok.Data;
import org.springframework.util.StringUtils;
@Data
public class GameClueVo {
private Integer id;
private Integer clueKey;
private String title;
private String tips;
private String tipsLogo;
private String photo;
private String qrcode;
public String getPhoto() {
if(StringUtils.isEmpty(photo)){
return "";
}
return ConstEnv.OSS_URL.concat(photo);
}
}
二、建立控制器@RestController controller类，如果只是告诉框架这是个控制器，定义@Controller即可
- 定义成员属性@Autowired Services类
- 定义方法和指定方法对外暴露的路径，使用get还是post还是其他
- 在方法中定义接受的参数@RequestParam("参数名")
- 调用具体的servers层
代码示例
package com.puzzle.api.controller;
import com.puzzle.api.service.GameClueService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class GameClueController {
@Autowired
private GameClueService gameClueService;
@GetMapping("/getClueInfo")
public Object getClueInfo(@RequestParam("id") Integer id){
return gameClueService.getClueInfo(id);
}
}
三、建立@Service services类
- 定义成员属性@Autowired private IMapper 接口;
- 编写方法，使用PO接受 mapper返回的数据
- 在方法内new VO()，最终以VO的数据格式返回
代码示例
package com.puzzle.api.service;
import com.puzzle.api.entity.po.GameClue;
import com.puzzle.api.entity.vo.GameClueVo;
import com.puzzle.api.mapper.IGameClueMapper;
import com.puzzle.api.utils.JsonResult;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class GameClueService {
@Autowired
private IGameClueMapper gameClueMapper;
public Object getClueInfo(Integer id){
try {
GameClue clueInfo = gameClueMapper.getClueInfo(id);
GameClueVo gameClueVo = new GameClueVo();
BeanUtils.copyProperties(clueInfo,gameClueVo);
return JsonResult.success(gameClueVo);
}catch (Exception e){
return JsonResult.failure(1102,"找不到线索");
}
}
}
四、建立@Resource IMapper接口
- 定义方法返回类型和入参名称和类型
代码示例
package com.puzzle.api.mapper;
import com.puzzle.api.entity.po.GameClue;
import org.apache.ibatis.annotations.Param;
import javax.annotation.Resource;
@Resource
public interface IGameClueMapper {
GameClue getClueInfo(@Param("id") Integer id);
}
五、建立与IMapper对应的XML文件，相当于框架会根据这个XML文件，自动帮我们编写一个对应的实现类
代码示例
<?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">
<!--定义命名空间为IMapper-->
<mapper namespace="com.puzzle.api.mapper.IGameClueMapper">
<!--XML定义返回数据类型为pojo类-->
<resultMap id="GameClue" type="com.puzzle.api.entity.po.GameClue">
<result column="id" jdbcType="INTEGER" property="id"/>
<result column="clue_key" jdbcType="INTEGER" property="clueKey"/>
<result column="title" jdbcType="VARCHAR" property="title"/>
<result column="tips" jdbcType="VARCHAR" property="tips"/>
<result column="tips_logo" jdbcType="VARCHAR" property="tipsLogo"/>
<result column="photo" jdbcType="VARCHAR" property="photo"/>
<result column="local" jdbcType="VARCHAR" property="local"/>
<result column="qrcode" jdbcType="VARCHAR" property="qrcode"/>
<result column="status" jdbcType="INTEGER" property="status"/>
<result column="c_time" jdbcType="INTEGER" property="cTime"/>
<result column="u_time" jdbcType="INTEGER" property="uTime"/>
<result column="del" jdbcType="INTEGER" property="del"/>
</resultMap>
<select id="getClueInfo" resultType="GameClue">
select `id`,`clue_key`,`title`,`tips`,`tips_logo`,`photo`,`qrcode` from game_clue where id=#{id} limit 1
</select>
</mapper>
附录
- application.properties
文件放置在：\src\main\resources
server.port=8001
#数据库配置
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/puzzle?&autoReconnect=true&useSSL=false&zeroDateTimeBehavior=convertToNull
spring.datasource.username=root
spring.datasource.password=root
#设置mapper.xml文件的地址
mybatis.mapper-locations=classpath:mapping/*Mapper.xml
#设置pojo类所在的包
mybatis.type-aliases-package=com.puzzle.api.entity.po
#设置字段名自动转java驼峰式命名
mybatis.configuration.map-underscore-to-camel-case=true
#设置mybatis日志打印
logging.level.com.nbhysj.demo.mapper=debug
- Spring boot入口启动文件: ApiApplication
文件路径：\src\main\java\com\puzzle\api
package com.puzzle.api;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@MapperScan("com.puzzle.api.mapper")
@SpringBootApplication
public class ApiApplication {
public static void main(String[] args) {
SpringApplication.run(ApiApplication.class, args);
}
}
- 项目结构：
/main
/main/java
/main/java/com.puzzle.api
/main/java/com.puzzle.api/controller
/main/java/com.puzzle.api/entity
/main/java/com.puzzle.api/entity/po
/main/java/com.puzzle.api/entity/vo
/main/java/com.puzzle.api/mapper
/main/java/com.puzzle.api/service
/main/java/com.puzzle.api/utils
//框架启动文件
/main/java/com.puzzle.api/ApiApplication
//静态文件和环境配置
/main/resources
//保存XML文件
/main/resources/mapping
备注：一个不规范的流程示意图，可能只有自己看的懂
image.png
GitHub地址: https://github.com/smartwill/ssm_api_demo
或 git clone https://github.com/smartwill/ssm_api_demo.git
database/game_clue.sql 导入数据库
