Data check
during web development, a request for a parameter, the parameter generally requires the legitimacy check, when writing a previous fields one to judge, in this way too general, so the java JSR 303: Bean Validation specification is to solve this problem.
JSR 303 is just a specification, no specific implementation, the current is usually only hibernate-validator unified parameter check.
Parity type defined JSR303
Detailed the Constraint
@null annotated element must be null
@NotNull annotated element must not be null
@AssertTrue annotated element must be true
annotated element must @AssertFalse to false
@min (value ) annotated element must be a number whose value must be greater than the specified minimum
@Max (value) annotated element must be a number whose value is equal to the specified maximum value must be less than
@DecimalMin (value) to be annotated must be a number of elements which must be greater than equal to the specified minimum value
@DecimalMax (value) annotated element must be a number whose value is equal to the specified maximum value must be less than
@Size (max, min) of the element to be annotated size must be within the specified range
@Digits (integer, fraction) annotated element must be a number whose value must be within an acceptable range
@Past annotated element must be a date in the past
@Future element annotated It must be a future date
@Pattern (value) annotated elements must comply with the specified regular expression
Hibernate Validator additional constraint
the Constraint details
@Email annotated element must be the email address
@Length string must be annotated within the specified size range
@NotEmpty annotated non-empty string must
@Range annotated element must be within the appropriate range
to create entity classes
@Data
@NoArgsConstructor
@AllArgsConstructor
public class DemoReq {
@NotBlank (Message = "code can not be blank")
String code;
@Length (max = 10, Message = "name length can not exceed 10 ")
String name;
}
then the control layer method adding to @Valid, so before the access request parameters will be tested.
@GetMapping ( "/ Demo / Valid")
public String demoValid (@Valid DemoReq REQ) {
return req.getCode () + "," + req.getName ();
}