Java Dom4j XML用法总结

1、新建XML文档：

             Document doc = DocumentHelper.createDocument();

            Element root = doc.addElement( "ocs");

            root.addElement( "header");

            Element body = root.addElement( "body");

            Element fontnode = body.addElement( "font");

            fontnode.addAttribute( "size", "9");

            System. out.println(root.asXML());

 

2、打开现有XML文档（从字符串导入）：

           Document doc = DocumentHelper.parseText(XMLStr);

            Node node = doc.selectSingleNode( "ocs/body/font");    

             if (node instanceof Element)

            {

                  Element pnode = (Element) node;           

                  Attribute attr = pnode.attribute( "size");

                  System. out.println(attr.asXML());

            }

 

          Dom4j中内置了XPath，因此可以在selectSingleNode中象XPath那样访问路径字符串；

          注意：需要引用jaxen-1.1.1.jar包，否则selectSingleNode会产生异常并返回Null;

 

3、打开现有文档（从文件导入）：

          SAXReader saxReader = new SAXReader();

          Document document = saxReader.read( XMLFile);

 

4、将Document写入到文件中:

          try

            {

                  XMLWriter output = new XMLWriter( new FileWriter( new File(XMLFile)));

                  output.write( doc);

                  output.close();

            } catch (IOException e)

            {

                  System. out.println(e.getMessage());

            }