code: public String getStreamHeader() {
      StringBuilder builder = new StringBuilder();
      builder.append("GDAT").append(Constants.NEWLINE).append("VERSION:").append(VERSION).append(Constants.NEWLINE)
        .append("SCHEMALENGTH:");
      String streamTree = getStreamParseTree();
      int headerLength = streamTree.length();
      builder.append(Integer.toString(headerLength));
      builder.append(Constants.NEWLINE);
      builder.append(streamTree);
      return builder.toString();
    }
docs: "GDAT\nVERSION:%u\nSCHEMALENGTH:%u\n"
  SchemaLength : The size of StreamTree.