code: private void process(Object entity, MetamodelImpl metamodel, Row row, Set<Attribute> attributes, Table schemaTable,
              EntityMetadata metadata)
      {
  
          for (Attribute attribute : attributes)
          {
              // by pass association.
              if (!attribute.isAssociation())
              {
                  // in case of embeddable id.
                  if (attribute.equals(metadata.getIdAttribute())
                          && metamodel.isEmbeddable(((AbstractAttribute) attribute).getBindableJavaType()))
                  {
                      processEmbeddableAttribute(entity, metamodel, row, schemaTable, metadata, attribute);
                  }
                  else
                  {
                      if (metamodel.isEmbeddable(((AbstractAttribute) attribute).getBindableJavaType()))
                      {
                          processEmbeddableAttribute(entity, metamodel, row, schemaTable, metadata, attribute);
                      }
                      else
                      {
                          setField(row, schemaTable, entity, attribute);
                      }
                  }
              }
          }
      }
docs: Iterate and store attributes.
  
  @param entity
  JPA entity.
  @param metamodel
  JPA meta model.
  @param row
  kv row.
  @param attributes
  JPA attributes.
  @param schemaTable
  the schema table
  @param metadata
  the metadata