/**
  * INTERNAL: Verify that getter returnType is correct for the indirection policy. If it is
  * incorrect, add an exception to the integrity checker. In this case, the return type CANNOT be
  * ValueHolderInterface.
  */
 public void validateGetMethodReturnType(Class returnType, IntegrityChecker checker)
     throws DescriptorException {
   super.validateGetMethodReturnType(returnType, checker);
   if (!this.typeIsValid(returnType)) {
     checker.handleError(
         DescriptorException.returnAndMappingWithoutIndirectionMismatch(this.mapping));
   }
 }