使用Dom4J解析XML(二)-优快云博客

本文介绍如何使用DOM4J库解析XML文件，并通过XPath选择节点进行修改，包括属性和文本内容的更新。演示了如何批量修改XML文档中的属性值、文本内容，并展示了如何利用Visitor模式遍历文档。

3.生成xml文件

package domj4Parser;

import java.util.List;
import java.util.Iterator;
import java.io.*;
//导入 dom4j API 类
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.Attribute;
import org.dom4j.Node;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.XMLWriter;
import org.dom4j.DocumentException;
import org.dom4j.io.SAXReader;

public class Dom4Jparser{
    public void modifyDocument(File inputXml){
        try{
            //使用 SAXReader 解析 XML 文档 catalog.xml
            SAXReader saxReader = new SAXReader();
            //inputXml 是从 catalog.xml 创建的 java.io.File
            Document document = saxReader.read(inputXml);

            //使用 XPath 表达式从 article 元素中获得 level 节点列表
            List list = document.selectNodes("//article/@level");
            Iterator iter=list.iterator();
            while(iter.hasNext()){
                //如果 level 属性值是"Intermediate"则改为"Introductory"
                Attribute attribute=(Attribute)iter.next();
                if(attribute.getValue().equals("Intermediate"))
                    attribute.setValue("Introductory");
            }

            list = document.selectNodes("//article/@date" );

            iter=list.iterator();
            while(iter.hasNext()){
                Attribute attribute=(Attribute)iter.next();
                if(attribute.getValue().equals("December-2001"))
                    attribute.setValue("October-2002");
            }

            //获取 article 元素列表
            list = document.selectNodes("//article" );
            iter=list.iterator();
            while(iter.hasNext()){
                Element element=(Element)iter.next();
                //使用Visitor模式遍历子节点
                element.accept(new MyVisitor());
                //从 article 元素中的 title 元素得到一个迭代器
                Iterator iterator=element.elementIterator("title");
                while(iterator.hasNext()){
                    Element titleElement=(Element)iterator.next();
                    //并修改 title 元素的文本
                    if(titleElement.getText().equals("Java configuration with XMLSchema"))
                        titleElement.setText("Create flexible and extensible XML schema");
                }
            }
            list = document.selectNodes("//article/author" );
            iter=list.iterator();
            while(iter.hasNext()){
                Element element=(Element)iter.next();
                Iterator iterator=element.elementIterator("firstname");
                while(iterator.hasNext()){
                    Element firstNameElement=(Element)iterator.next();
                    if(firstNameElement.getText().equals("Marcello"))
                        firstNameElement.setText("Ayesha");
                }
            }
            list = document.selectNodes("//article/author" );
            iter=list.iterator();
            while(iter.hasNext()){
                Element element=(Element)iter.next();
                Iterator iterator=element.elementIterator("lastname");
                while(iterator.hasNext()){
                    Element lastNameElement=(Element)iterator.next();
                    if(lastNameElement.getText().equals("Vitaletti"))
                        lastNameElement.setText("Malik");
                }
            }
            XMLWriter output = new XMLWriter(
                    new FileWriter( new File("xmlFile/catalog-modified.xml")));
            output.write(document);
            output.close();
        }
        catch(DocumentException e){
            e.printStackTrace();
        }
        catch(IOException e){
            System.out.println(e.getMessage());
        }
    }
    public void treeWalk(Element element) {
        for (int i = 0,size = element.nodeCount();i < size;i++){
            Node node = element.node(i);
            if (node instanceof Element) {
                treeWalk((Element) node);
            }
            else { /* do something....*/}
        }
    }
    //处理中文问题
    public int formatXMLFile(String filename){
        int returnValue = 0;
        try{
           SAXReader saxReader = new SAXReader();
           Document document = saxReader.read(new File(filename));
           XMLWriter output = null;
           /** 格式化输出,类型IE浏览一样 */
           OutputFormat format = OutputFormat.createPrettyPrint();
           /** 指定XML字符集编码 */
           format.setEncoding("GBK");
           output = new XMLWriter(new FileWriter(new File(filename)),format);
           output.write(document);
           output.close();
           /** 执行成功,需返回1 */
           returnValue = 1;
        }
        catch(Exception ex){
            ex.printStackTrace();
        }
        return returnValue;
    }

    public static void main(String[] argv){
        Dom4Jparser dom4jParser=new Dom4Jparser();
        dom4jParser.modifyDocument(new File("xmlFile/catalog.xml"));
        dom4jParser.formatXMLFile("xmlFile/catalog.xml");
    }
}
4.使用Visitor模式

package domj4Parser;

import org.dom4j.Attribute;
import org.dom4j.Element;
import org.dom4j.VisitorSupport;

//Visitor模式
public class MyVisitor extends VisitorSupport {
    public void visit(Element element){
         System.out.println(element.getName());
    }
    public void visit(Attribute attr){
         System.out.println(attr.getName());
    }
}