1、接口注释
@Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER})
@Retention(RUNTIME)
@Documented
@Constraint(validatedBy
= {IncrementalValidator.
class
})
public
@
interface
IncrementalInteger {
String message()
default
"{common.incrementalInteger.Pattern}"
;
Class
<?>[] groups()
default
{};
Class
<?
extends
Payload>[] payload()
default
{};
/**
*
@return
value the element must be larger or equal to
*/
int
min();
/**
*
@return
value the element must be smaller or equal to
*/
int
max();
/**
*
@return
value must be incremental
*/
int
increment();
/**
* Defines several {
@link
IncrementalInteger} annotations on the same
* element.
*
*
@see
IncrementalInteger
*/
@Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER})
@Retention(RUNTIME)
@Documented
@
interface
List {
IncrementalInteger[] value();
}
}
2、Validator类
public
class
IncrementalValidator
implements
ConstraintValidator<IncrementalInteger, Integer>
{
private
IncrementalInteger constraintAnnotation;
@Override
public
void
initialize(IncrementalInteger constraintAnnotation) {
this
.constraintAnnotation =
constraintAnnotation;
}
@Override
public
boolean
isValid(Integer value, ConstraintValidatorContext context) {
int
min =
constraintAnnotation.min();
int
increment =
constraintAnnotation.increment();
int
max =
constraintAnnotation.max();
if
(value <
min) {
return
false
;
}
if
(value >
max) {
return
false
;
}
if
((value - min) % increment != 0
) {
return
false
;
}
return
true
;
}
}
