dom4j操作xml

 public static void main(String args[]) {
	try {
	    SAXReader reader = new SAXReader();
	    Document document = reader.read(new File("d:\\aa.xml"));
	    Element el = document.getRootElement();
	    
	    //得到service节点
	    Iterator iterator = el.elementIterator("service");
	    Element sel = (Element) iterator.next();
	    //得到service节点下面的所有节点 
	    //为了判断service节点下面有没有value,title等其他节点
	    //如果已经有了就删除了 重新添加 没有的话 就直接添加
	    Iterator iter = sel.elementIterator();
	    //遍历service下的所有节点
	    while(iter.hasNext()){
		
		Element el2 = (Element)iter.next();
		//如果有value节点 删除它
		if(el2.getName() == "value"){
		    sel.remove(el2);
		}
		//如果有title节点 删除它
		if(el2.getName() == "title"){
		    sel.remove(el2);
		}
	    }
	    //在service节点下创建value节点
	    Element value = sel.addElement("value");
	    //给value节点赋值
	    value.setText("laop");

	    //在service节点下创建title节点
	    Element title = sel.addElement("title");
	    //给title节点赋值
	    title.setText("老婆");
	    
	    //把生成好的xml写入地址
	    //美化格式
	    OutputFormat format = OutputFormat.createPrettyPrint();  
	    XMLWriter writer = new XMLWriter(new FileWriter(new File("d:\\aa.xml")),format);
	    writer.write(document);
	    writer.close();

	} catch (Exception e) {
	}

    }

XML文件

<?xml version="1.0" encoding="UTF-8"?>
<books> 
  <service> 
    <value>laop</value>
    <title>老婆</title>
  </service>  
  <ss>ssssss</ss> 
</books>

------------------------------------------------------------------------------------------------8月21号--------

Iterator iterator = el.elementIterator("action");
			while (iterator.hasNext()) {
				Element sel = (Element) iterator.next();
				Iterator iter = sel.elementIterator();
				while (iter.hasNext()) {
					Element el2 = (Element) iter.next();
					Iterator iter3 = el2.elementIterator();
					while (iter3.hasNext()) {
						Element el3 = (Element) iter3.next();
						//这个方法可以
						System.out.println(el3.getText());
						//下面这个不行
						System.out.println(el3.elementText("function"));
					}
				}
			}