private void doModification(final FieldMetadata field, final CustomData customData) {
   MemberHoldingTypeDetails memberHoldingTypeDetails =
       memberHoldingTypeDetailsMap.get(field.getDeclaredByMetadataId());
   if (memberHoldingTypeDetails != null) {
     FieldMetadata matchedField = memberHoldingTypeDetails.getField(field.getFieldName());
     if (matchedField != null
         && !matchedField.getCustomData().keySet().containsAll(customData.keySet())) {
       TypeDetailsBuilder typeDetailsBuilder = getTypeDetailsBuilder(memberHoldingTypeDetails);
       typeDetailsBuilder.addDataToField(field, customData);
       changed = true;
     }
   }
 }