GwtValidatorImpl Inside SampleValidatorFactory is not compiling in Intellij , trying gwt-bean-valiadator version 1.5.0

Issue facing: In gwt-bean-valiadtor from version 1.6.0, its mentioned to declare GwtValiadtor like :

public final class SampleValidatorFactory extends AbstractGwtValidatorFactory {

  /**
   * Validator marker for the Validation Sample project. Only the classes and groups listed
   * in the {@link GwtValidation} annotation can be validated.
   */
  @GwtValidation(Person.class)
  public interface GwtValidator extends Validator {
  }

  @Override
  public AbstractGwtValidator createValidator() {
  **  return new GwtValidatorImpl();**-- Intellij build and explicit maven build is complaining giving complier error :
  }
}

and GwtValidatorImpl will be generated by annotation driven code generation, but this is not generating and giving compiler error Error:

Current State: gwt-bean-valiadator working with version 1.2.0 with defined create Validator Like

@Override public AbstractGwtValidator createValidator() {

    return GWT.create(GwtValidator.class);
}