code: public void save(Writer writer) throws IOException {
          BufferedWriter bufferWriter = new BufferedWriter(writer);
          writePrefixDeclaration(bufferWriter);
          writeMappingDeclaration(bufferWriter);
          bufferWriter.flush();
          bufferWriter.close();
      }
docs: The save/write operation.
  
  @param writer
  The target writer to which the model is saved.
  @throws IOException