code: public static String getVertexId(Value value) {
          byte[] buffer = value.get();
          int offset = 0;
  
          // skip label
          int strLen = readInt(buffer, offset);
          offset += 4;
          if (strLen > 0) {
              offset += strLen;
          }
  
          strLen = readInt(buffer, offset);
          return readString(buffer, offset, strLen);
      }
docs: fast access method to avoid creating a new instance of an EdgeInfo