public static List<AttributeDetail> convertDTOs(List<AttributeDTO> attributesDTO) {
   assert (attributesDTO != null) : "Attributes DTO must be not null.";
   List<AttributeDetail> attributes =
       Lists.<AttributeDetail>newArrayListWithCapacity(attributesDTO.size());
   for (AttributeDTO attributeDTO : attributesDTO) {
     attributes.add(FeatureConverter.convert(attributeDTO));
   }
   return attributes;
 }
 public static List<AttributeDTO> convertDetails(List<AttributeDetail> attributes) {
   assert (attributes != null) : "Attributes must be not null.";
   List<AttributeDTO> attributesDTO =
       Lists.<AttributeDTO>newArrayListWithCapacity(attributes.size());
   for (AttributeDetail attribute : attributes) {
     attributesDTO.add(FeatureConverter.convert(attribute));
   }
   return attributesDTO;
 }
 public QueryRestrictionDTO getQueryRestriction() {
   QueryRestrictionDTO queryRestriction = null;
   AttributeDetail attributeDetail = this.nameAttributeCombo.getValue();
   String operator = this.operatorCombo.getValue().getValue();
   String restriction = this.conditionAttributeField.getValue();
   if (attributeDetail != null
       && operator != null
       && this.conditionAttributeField.isValid()
       && restriction != null) {
     AttributeDTO attributeDTO = FeatureConverter.convert(attributeDetail);
     queryRestriction = new QueryRestrictionDTO(attributeDTO, operator, restriction);
   }
   return queryRestriction;
 }