使用DOM4J解析xml文件开发步骤及例子

 

编写xmlReader.java
 
package com.xml.dom4j;
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 XMLReader {
      
       public void read(String fileName) throws DocumentException{
              File xmlFile = new File(fileName);
              read(xmlFile);
       }
      
       @SuppressWarnings("unchecked")
       public void read(File xmlFile) throws DocumentException{
              //使用SAX方式解析xml
              SAXReader saxReader = new SAXReader();
              //把xml文件转换成文档对象
               Document document = saxReader.read(xmlFile);
               //取得根节点
               Element rootNode = document.getRootElement();
              //取得根节点的名字
               System.out.println("根节点名称: "+rootNode.getName());
              //取得所有的二级(下一级)子节点
               List secondList =  rootNode.elements();
               readsecondLevelElement(secondList);
              
       }
      
       @SuppressWarnings("unchecked")
       public void readsecondLevelElement( List secondList){
              for(Element secondElement : secondList){
                      System.out.println(" \t二级节点名称:"+secondElement.getName());
                      //取得所有的二级子节点的属性
                      System.out.println(" \t    属性title:"+secondElement.attributeva lue("title")+" 属性publisher:"+secondElement.attributeva lue("publisher"));
                     //取得所有的三级(下一级)子节点
                      List thirdList =  secondElement.elements();
                      readThirdLevelElement(thirdList);
               }
       }
      
       @SuppressWarnings("unchecked")
       public void readThirdLevelElement( List thirdList){
              for(Element thirdElement : thirdList){
                      System.out.println(" \t\t三级节点名称:"+thirdElement.getName());
                     //取得所有的三级子节点的属性
                      System.out.println(" \t\t     属性level:"+thirdElement.attributeva lue("level")+" 属性date:"+thirdElement.attributeva lue("date"));
                     //取得所有的四级(下一级)子节点
                      List fourList =  thirdElement.elements();
                      readFourLevelElement(fourList);
               }
       }
      
       //读取四级元素的方法
       public void readFourLevelElement( List fourList){
               for(Element fourElement : fourList){
                      System.out.println(" \t\t\t四级节点名称:"+fourElement.getName());
                     if(fourElement.getName().equals("title")){
                            System.out.println(" \t\t\t     四级节点内容:"+fourElement.getText());
                     }else if(fourElement.getName().equals("author")){
                            //fourElement.element("firstname") 通过名字取得firstname节点
                            System.out.println(" \t\t\t\t五级级节点内容:"+fourElement.element("firstname").getName());
                            System.out.println(" \t\t\t\t        五级节点内容:"+fourElement.element("firstname").getText());
                            System.out.println(" \t\t\t\t五级级节点内容:"+fourElement.element("lastname").getName());
                            System.out.println(" \t\t\t\t        五级节点内容:"+fourElement.element("lastname").getText());
                     }
               }
       }
}
 
 
 
编写测试类
 @Test
 public void testRead() {
              try {
                     String file = "F:/students/dom4j_XML/src/catalog.xml";
                     XMLReader reader = new XMLReader();
                     reader.read(file);
              } catch (DocumentException e) {
              }
       }
项目结构:
 
 
要点说明:
  使用dom4j方式解析xml:
   
     1.指定要解析的文件
       File xmlFile = new File(fileName);
     2.选择xml解析方式
       //使用SAX方式解析xml
              SAXReader saxReader = new SAXReader();
        3.解析xml文件
         //把xml文件转换成文档对象
               Document document = saxReader.read(xmlFile);
     4.解析文档对象dom对象
               //取得根节点
               Element rootNode = document.getRootElement();
               //取得所有的下一级节点
               List secondList =  rootNode.elements();
               //根据名字取的子节点
               fourElement.element("firstname")
               //根据名字取的子节点,和节点内容
               fourElement.element("firstname").getText()
               //根据名字取的节点属性值
               thirdElement.attributeva lue("level")