dom解析案例

 

public class Demo4jDemo2 {  

@Test

 public void attr() throws Exception{   

SAXReader reader = new SAXReader();

  Document dom = reader.read("book.xml");

  Element root = dom.getRootElement();     

 Element bookEle = root.element("书");  

 //bookEle.addAttribute("出版社", "出版社");

//  String str = bookEle.attributeValue("出版社");

//  System.out.println(str);   Attribute attr = bookEle.attribute("出版社");

  attr.getParent().remove(attr);     

 XMLWriter writer = new XMLWriter(new FileOutputStream("book.xml"),OutputFormat.createPrettyPrint());

  writer.write(dom);   

writer.close();  

}  

 @Test

 public void del() throws Exception{  

 SAXReader reader = new SAXReader();  

 Document dom = reader.read("book.xml");

  Element root = dom.getRootElement();     

 Element price2Ele = root.element("书").element("特价");

  price2Ele.getParent().remove(price2Ele);

  XMLWriter writer = new XMLWriter(new FileOutputStream("book.xml"),OutputFormat.createPrettyPrint());   

writer.write(dom);   

writer.close();

 }  

 @Test  public void update()throws Exception{  

 SAXReader reader = new SAXReader();  

 Document dom = reader.read("book.xml");

  Element root = dom.getRootElement();     

 root.element("书").element("特价").setText("4.0元");

     XMLWriter writer = new XMLWriter(new FileOutputStream("book.xml"),OutputFormat.createPrettyPrint());

  writer.write(dom);   

writer.close();

 }  

 @Test

 public void add()throws Exception{   

SAXReader reader = new SAXReader();

  Document dom = reader.read("book.xml");

  Element root = dom.getRootElement();  

 //凭空创建<特价>节点,设置标签体

  Element price2Ele = DocumentHelper.createElement("特价");  

 price2Ele.setText("40.0元");

  //获取父标签<书>将特价节点挂载上去

  Element bookEle = root.element("书");   

bookEle.add(price2Ele);      

//将内存中的dom树会写到xml文件中,从而使xml中的数据进行更新

//  FileWriter writer = new FileWriter("book.xml");

//  dom.write(writer);

//  writer.flush();

//  writer.close();  

 XMLWriter writer = new XMLWriter(new FileOutputStream("book.xml"),OutputFormat.createPrettyPrint());

  writer.write(dom);   

writer.close();  }  

 @Test

 public void find() throws Exception{   

SAXReader reader = new SAXReader();   

Document dom = reader.read("book.xml");

  Element root = dom.getRootElement();   

  List<Element> list =  root.elements();   

Element book2Ele = list.get(1);  

 System.out.println(book2Ele.element("书名").getText());     } }