code: public Entity toEntity(final EntityType meta, final Map<String, Object> request) {
      final Entity entity = entityManager.create(meta, POPULATE);
  
      for (Attribute attr : meta.getAtomicAttributes()) {
        if (attr.getExpression() == null) {
          String paramName = attr.getName();
          if (request.containsKey(paramName)) {
            final Object paramValue = request.get(paramName);
            Attribute idAttribute = meta.getIdAttribute();
            Object idValue = request.get(idAttribute.getName());
            final Object value = this.toEntityValue(attr, paramValue, idValue);
            entity.set(attr.getName(), value);
          }
        }
      }
  
      return entity;
    }
docs: Creates a new entity based from a HttpServletRequest. For file attributes persists the file in
  the file store and persist a file meta data entity.
  
  @param meta entity meta data
  @param request HTTP request parameters
  @return entity created from HTTP request parameters