Springboot后台管理系统(六)SpringBoot实现增删改查

UserController

@RestController
@RequestMapping("/user")
public class UserController {

    @Autowired
    private UserMapper userMapper;

    @PostMapping
    public Integer save(@RequestBody User user){
        //@RequestBody将前台json转换为user对象
        return userMapper.insert(user);
    }

    @GetMapping
    public List index(){
        return userMapper.findAll();
    }
}

UserMapper

@Insert("INSERT into sys_user(username,password,nickname,email,phone,address) VALUES (#{username},#{password},#{nickname},#{email},#{phone},#{address});")
int insert(User user);

SQL

INSERT into sys_user(username,password,nickname,email,phone,address) 
VALUES("zhu","123456","猪头","zhu@qq.com","13677798889","高老庄");

postman测试接口

进行判断用户的id是否为空，来分清楚是新增还是修改
UserController

@RestController
@RequestMapping("/user")
public class UserController {

    @Autowired
    private UserMapper userMapper;

    @Autowired
    private UserService userService;

    
    @PostMapping
    public Integer save(@RequestBody User user){
        //@RequestBody将前台json转换为user对象
        return userService.save(user);
    }

    @GetMapping
    public List index(){
        return userMapper.findAll();
    }
}

UserService

@Service
public class UserService {

    @Autowired
    private UserMapper userMapper;

    public int save(User user){
        if(user.getId() == null){
            //user没有id，表示是新增
            return userMapper.insert(user);
        }else{
            //否则，为更新
            return userMapper.update(user);
        }
    }

UserMapper

@Mapper
public interface UserMapper {

    
    @Select("select * from sys_user")
    List findAll();

    
    @Insert("INSERT into sys_user(username,password,nickname,email,phone,address) VALUES (#{username},#{password},#{nickname},#{email},#{phone},#{address})")
    int insert(User user);


    
    int update(User user);
}

为了防止修改时，将一些数据置空，使用动态sql
User.xml

    
        update sys_user
        
            
                username=#{username},
            



            
                nickname=#{nickname},
            
            
                email=#{email},
            
            
                phone=#{phone},
            
            
                address=#{address}
            

        
        
            id = #{id}
        
    

使用postman测试

出现错误

添加配置文件

mybatis:
  mapper-locations: mapper/*.xml

配置文件 增加控制台输出显示

mybatis:
  mapper-locations: mapper/*.xml #扫描所有mybatis的xml文件
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

UserController

@DeleteMapping("/{id}")
public Integer delete(@PathVariable Integer id){
    return userMapper.deleteById(id);
}

UserMapper

@Delete("delete from sys_user where id = #{id}")
Integer deleteById(@Param("id") Integer id);

测试