Spring Boot 知识笔记（整合Mybatis续-补充增删改查）

续上篇，补充数据库增删改查的其他场景。

一、Mapper中添加其他场景操作

package net.Eleven.demo.Mapper;

import net.Eleven.demo.domain.UserNew;

import org.apache.ibatis.annotations.*;

import java.util.List;

/**

 * 功能描述：访问数据库的接口，相当于dao层

 * @author Eleven

 */

public interface UserMapper {

    //推荐使用#{}取值，不要用${},因为存在注入的风险

    /**

     * 向数据库插入一条数据

     * @param userNew

     * @return

     */

    @Insert("INSERT INTO user(name,phone,create_time,age) VALUES(#{name},#{phone},#{creatTime},#{age})")

    @Options(useGeneratedKeys = true,keyProperty = "id",keyColumn = "id") //keyProperty java对象的属性；keyColumn表示数据库的字段

    int insert(UserNew userNew);

    /**

     * 查找全部，功能比较简单，也可以直接跳过service层，直接在controller注入mapper

     * @return

     */

    @Select("select * from user")

    @Results({@Result(column = "create-time",property = "createTime")})

    List<UserNew> getAllUser();

    /**

     * 根据id查询，返回的是一个user对象

     * @param id

     * @return

     */

    @Select("select * from user where id=#{id}")

    @Results({@Result(column = "create-time",property = "createTime")})

    UserNew  findById(int id);

    /**

     * 根据id更新对象的name

     * @param userNew

     */

    @Update("update user set name=#{name} where id=#{id}")

    void updateById(UserNew userNew);

    /**

     * 根据id，删除一个对象

     */

    @Delete("delete from user where id =#{id}")

    void deleteById(int id);

}

二、impl文件中增加对应的调用mapper的方法

package net.Eleven.demo.Service.impl;

import net.Eleven.demo.Mapper.UserMapper;

import net.Eleven.demo.Service.UserService;

import net.Eleven.demo.domain.UserNew;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

import javax.validation.constraints.Null;

import java.util.List;

@Service

public class UserServiceImpl implements UserService {

    @Autowired

    private UserMapper userMapper;

    @Override

    public int add(UserNew userNew) {

        userMapper.insert(userNew);

        int id = userNew.getId();

        return id;

    }

    //查找所有，对应mapper的getAlluser

    public Object findAll(){

        return userMapper.getAllUser();

    }

    //根据id查找，对应mapper的findById

    public Object findById(int id){

        return userMapper.findById(id);

    }

    //更新一个对象

    public void updateById(UserNew userNew){

         userMapper.updateById(userNew);

    }

    //删除一个对象

    public  void deleteById(int id){

        userMapper.deleteById(id);

    }

}

三、controller中增加对应的request请求，通过注入，调用impl的方法，继而执行数据库命令。

package net.Eleven.demo.controller;

import net.Eleven.demo.Service.UserService;

import net.Eleven.demo.Service.impl.UserServiceImpl;

import net.Eleven.demo.domain.JsonData;

import net.Eleven.demo.domain.UserNew;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.GetMapping;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

import java.util.Date;

@RestController

@RequestMapping("/api/sql/user")

public class UserController {

    @Autowired

    private UserService userService;

    @Autowired

    private UserServiceImpl userServiceImpl;

    @GetMapping("add")

    public Object userAdd(){

        UserNew userNew = new UserNew();

        userNew.setAge(11);

        userNew.setCreatTime(new Date());

        userNew.setName("Eleven");

        userNew.setPhone("18211111111");

        int id = userService.add(userNew);

        return JsonData.buildSuccess(id);

    }

    //查找全部

    @GetMapping("find_all")

    public Object findAll(){

        return JsonData.buildSuccess(userServiceImpl.findAll());

    }

    //根据id查找对象

    @GetMapping("find_by_id")

    public Object findById(int id){

        return JsonData.buildSuccess(userServiceImpl.findById(id));

    }

    //根据id更新对象的name

    @GetMapping("update_by_id")

    public Object updateById(String name,int id){

         UserNew userNew = new UserNew();

        userNew.setName(name);

        userNew.setId(id);

        userServiceImpl.updateById(userNew);

        return JsonData.buildSuccess();

    }

    //根据id删除对象

    @GetMapping("delete_by_id")

    public  Object deleteById(int id){

        userServiceImpl.deleteById(id);

    }

}

四、执行结果