XML文档解析

　　

   static Document document=null;
   static Element root-null;
   static Scanner input=new Scanner(System.in);

1.获取xml文件：

    //创建解析器
SAXReader reader=new SAXReader();
try{
    //读取xml文件
    document=reader.read("xml相对路径")；
    //获取根节点
    root=document.getRootElement();
}catch(DocumentException e){
    e.printStackTrace();
}

2.

把内存中的保存到xml文档中

//创建输出流对象
XMLWriter writer=null;
//设置格式化
OutputFormat format=null;
format=OutputFormat.creatPrettyPrint();
try{
   writer=new XMLWriter(new FileWriter("xml文件相对路径")，format)   
   //真正的写入
   writer.write(document);
   
}catch (IOException e) {
            e.printStackTrace();
}finally {
            try {
                writer.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

3.查看全部xml内容

Iterator<Element> books=rootNode.elementIterator();
//遍历
while(books.hasNext()){
   Element book = books.next();
    System.out.println("图书编号是："+book.attributeValue("id"));
   //通过图书编号获取图书名称
    Iterator<Element> bookName = book.elementIterator();
    //遍历图书信息
            while(bookName.hasNext()){
                Element bookz = bookName.next();
                System.out.println("图书id------>"+bookz.attributeValue("id"));
                System.out.println("图书型号------
              >"+bookz.attributeValue("name"));
                if(!bookz.getTextTrim().equals("")){
                    System.out.println("图书名称是:"+bookz.getTextTrim());
                }
            }

}

4.删除节点

//遍历整个dom 找到需要删除的节点
        Iterator<Element> books = rootNode.elementIterator();
        System.out.println("请输入要删除的bookId");
        String id=input.next();
        while(books.hasNext()){
            Element bookName = books.next();
            if(bookName.attributeValue("id").equals(id)){
                rootNode.remove(bookName);
            }
        }

5.修改节点

//遍历整个dom 找到需要修改的节点
        Iterator<Element> books = rootNode.elementIterator();
        System.out.println("请输入要修改的图书id：");
        String id=input.next();
        System.out.println("请输入修改后的id：");
        String ids=input.next();
        while(books.hasNext()){
            Element bookName = books.next();
            if(bookName.attributeValue("id").equals(id)){
                bookName.setAttributeValue("id",ids);
            }
        }

6.添加节点

//先从book根节点创建子节点
        System.out.println("请输入bookId的id：");
        String bid=input.next();
        Element bookId=rootNode.addElement("bookId");
        bookId.addAttribute("id",bid);
        System.out.println("请输入bookName的id：");
        String id=input.next();
        System.out.println("请输入bookName的name：");
        String name=input.next();
        System.out.println("请输入bookName的值：");
        String values=input.next();
        Element bookName=bookId.addElement("bookName");
        bookName.addAttribute("id",id);
        bookName.addAttribute("name",name);
        bookName.addText(values);