XML学习——java解析xml文件

递归获取每个标签

package test;

import java.io.File;
import java.util.List;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

public class test {
    
    public static void main(String[] args) {
        //1.获取dom4j解析对象
        SAXReader reader = new SAXReader();
        
        //2.获取要解析的xml文件
        try {
            Document document = reader.read(new File("./src/student.xml"));
            //3.获取根标签
            Element rootElement = document.getRootElement();
            
            getEachElement(rootElement);
            
            
        } catch (DocumentException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    public static void getEachElement(Element element) {
        System.out.println(element.getName());
        List<Element> elements = element.elements();
        if (elements!=null) {
            for (Element element2 : elements) {
                getEachElement(element2);
            }
        }
    }
    
}

运行结果

 获取标签属性

方法一：（foreach遍历）

List<Element> elements = rootElement.elements(); 
              for (Element element :elements) { 
                 String id = element.attributeValue("id");
                 String message = element.attributeValue("message");
                 System.out.println(id+"   "+message);
              }

方法二：(迭代器获取)

List<Element> elements = rootElement.elements(); 
              for (Element element :elements) { 
                
                  Iterator attributeIterator = element.attributeIterator();
                  while (attributeIterator.hasNext()) {
                    Attribute attribute = (Attribute)attributeIterator.next();  
                    
                    String name = attribute.getName();
                    String value = attribute.getValue();
                
                    System.out.println(name+"  "+value);
                    
                }
                  
        }    

把XML写在本地文件

Document docuement = reader.read(new File("./src/student.xml"));
            FileOutputStream fileOutputStream = new FileOutputStream("C:\message.xml");
            
            OutputFormat outputFormat = OutputFormat.createPrettyPrint();
            XMLWriter xmlWriter = new XMLWriter(fileOutputStream,outputFormat);
            outputFormat.setEncoding("utf-8");
            xmlWriter.write(docuement);
            fileOutputStream.close();
            xmlWriter.close();