package org.hibernate.validator.referenceguide.chapter02.typeargument.optional; import java.lang.annotation.Documented; import java.lang.annotation.Retention; import java.lang.annotation.Target; import javax.validation.Constraint; import javax.validation.ConstraintValidator; import javax.validation.ConstraintValidatorContext; import javax.validation.Payload; import static java.lang.annotation.ElementType.ANNOTATION_TYPE; import static java.lang.annotation.ElementType.CONSTRUCTOR; import static java.lang.annotation.ElementType.FIELD; import static java.lang.annotation.ElementType.METHOD; import static java.lang.annotation.ElementType.PARAMETER; import static java.lang.annotation.ElementType.TYPE_USE; import static java.lang.annotation.RetentionPolicy.RUNTIME; @Documented @Constraint(validatedBy = { MinTowingCapacity.MinTowingCapacityValidator.class }) @Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE }) @Retention(RUNTIME) public @interface MinTowingCapacity { long value(); String message() default "{org.hibernate.validator.referenceguide.chapter02.typeargument.MinTowingCapacity.message}"; Class<?>[] groups() default { }; Class<? extends Payload>[] payload() default { }; class MinTowingCapacityValidator implements ConstraintValidator<MinTowingCapacity, Integer> { private long min; @Override public void initialize(MinTowingCapacity annotation) { min = annotation.value(); } @Override public boolean isValid(Integer value, ConstraintValidatorContext context) { if ( value == null ) { return true; } return value >= min; } } }