Generating a error code per property in Hibernate Validator

Question

I am looking at using Hibernate Validator for a requirement of mine. I want to validate a JavaBean where properties may have multiple validation checks. For example:

class MyValidationBean
{
   @NotNull
   @Length( min = 5, max = 10 )
   private String myProperty;
}

But if this property fails validation I want a specific error code to be associated with the ConstraintViolation, regardless of whether it failed because of @Required or @Length, although I would like to preserve the error message.

class MyValidationBean
{
   @NotNull
   @Length( min = 5, max = 10 )
   @ErrorCode( "1234" )
   private String myProperty;
}

Something like the above would be good but it doesn't have to be structured exactly like that. I can't see a way to do this with Hibernate Validator. Is it possible?

Answer 1

You could create a custom annotation to get the behaviour you are looking for and then on validating and using refelection you could extract the value of the annotation. Something like the following:

@Target({ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
public @interface ErrorCode {
    String value();
}

In your bean:

@NotNull
@Length( min = 5, max = 10 )
@ErrorCode("1234")
public String myProperty;

On validating your bean:

Set<ConstraintViolation<MyValidationBean>> constraintViolations = validator.validate(myValidationBean);    
for (ConstraintViolation<MyValidationBean>cv: constraintViolations) {
    ErrorCode errorCode = cv.getRootBeanClass().getField(cv.getPropertyPath().toString()).getAnnotation(ErrorCode.class);
    System.out.println("ErrorCode:" + errorCode.value());
}

Having said that I probably would question the requirements for wanting error codes for these types of messages.