is there a way to use javax.validation to validate a variable of type string called colour that needs to have these values only(red, blue, green, pink) using annotations?
i have seen @size(min=1, max=25) and @notnull but is there something like this @In(red, blue, green, pink)
more or less similar to the In-keyword used in mysql
In that case I think it would be simpler to use the @Pattern annotation, like the snippet below. If you want a case insensitive evaluation, just add the appropriate flag:
@Pattern(regexp = "red|blue|green|pink", flags = Pattern.Flag.CASE_INSENSITIVE)
You can create a custom validation annotation. I will write it here (untested code!):
@Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER })
@Retention(RUNTIME)
@Documented
@Constraint(validatedBy = InConstraintValidator.class)
public @interface In
{
String message() default "YOURPACKAGE.In.message}";
Class<?>[] groups() default { };
Class<? extends Payload>[] payload() default {};
Object[] values(); // TODO not sure if this is possible, might be restricted to String[]
}
public class InConstraintValidator implements ConstraintValidator<In, String>
{
private Object[] values;
public final void initialize(final In annotation)
{
values = annotation.values();
}
public final boolean isValid(final String value, final ConstraintValidatorContext context)
{
if (value == null)
{
return true;
}
return ...; // check if value is in this.values
}
}
you can create an enum
public enum Colors {
RED, PINK, YELLOW
}
and then in your model, you can validate it like so:
public class Model {
@Enumerated(EnumType.STRING)
private Colors color;
}
which will validate your payload against the enum, given that you have added @Valid in your RestController.
null (though @NotNull could solve that). The issue is that it will likely throw some kind of deserialization error, and not be grouped with and handled the same way as the other validations.You can create your validation class by your own. for reference https://www.javatpoint.com/spring-mvc-custom-validation
