@NotNull, @NotEmpty, @NotBlank of elegant verification parameters

@NotNull, @NotEmpty, @NotBlank of elegant verification parameters

First explain the difference between the three annotations:

annotation	effect	data type (in general)
@NotNull	It cannot be null, it can be empty (that is, it can be "")	Integer, Long, BigDecimal, Date (you can use @size, @Max, @Min, @Range to limit Integer)
@NotEmpty	Cannot be null, and the length must be greater than 0	collection, array
@NotBlank	Not null, only works on String, and the length must be greater than 0 after calling trim(), that is, there must be actual characters	String (you can use @Length to limit the length)

usage:

1. Write the corresponding parameter verification annotation on the attribute value of the entity class

   public class UserRegisterDto implements Serializable {
         
         
       @NotBlank(message = "电话号码不可为空")
       @Schema(description = "电话号码", required = true)
       private String phone;
   
       @NotNull(message = "登录渠道不可为空")
       @Schema(description = "登录渠道", required = true)
       private Integer channel;
   }
   

2. Add the @@Valid annotation to the corresponding controller

   public class UserRegisterController {
         
         
   
       @PostMapping("/register")
       @Operation(summary = "c端用户注册接口", description = "c端注册")
       public HttpResult<UserInfo> register(@RequestBody @Valid UserRegisterDto dto) {
         
         
   		// TODO do something
           return HttpResult.success(userInfo);
       }
   
   }
   

**Note:** If the corresponding type is written incorrectly, an error will be reported. On my side, I wrote @NotEmpty on the channel field (Integer type), which resulted in the following error. Change it to @NotNull and it will be fine.

HV000030: No validator could be found for constraint 'javax.validation.constraints.NotEmpty' validating type 'java.lang.Integer'. Check configuration for 'channel'