code: public BaseJsonBo removeSubAttr(String attrName, String dPath) {
          Lock lock = lockForWrite();
          try {
              JsonNode attr = cacheJsonObjs.get(attrName);
              JacksonUtils.deleteValue(attr, dPath);
              return (BaseJsonBo) setAttribute(attrName, SerializationUtils.toJsonString(attr),
                      false);
          } finally {
              lock.unlock();
          }
      }
docs: Remove a sub-attribute.
  
  @param attrName
  @param dPath
  @return