使用DOM解析生成xml文档的代码，希望博友能解释一下，每行帮我加上明确的注释

悬赏园豆：10 [已关闭问题] 关闭于 2016-11-11 17:19

DOMImplementationRegistry registry =    DOMImplementationRegistry.newInstance();        //1

  DOMImplementationLS domImplLs =
      (DOMImplementationLS)registry.getDOMImplementation("LS");   //2

  LSSerializer serializer = domImplLs.createLSSerializer();   //3

  serializer.getDomConfig().setParameter("format-pretty-print", true); //4

  LSOutput out = domImplLs.createLSOutput(); //5
  out.setEncoding("GBK");

  File file = new File("./src/com/example/xml_dom/test02.xml"); //6
  if(!file.exists())
   file.createNewFile();
  out.setCharacterStream(new FileWriter(file));

  serializer.write(doc, out); //7