使用dom4j 操作xml文件

使用dom4j 可以很快對xml 文檔進行操作

需要導入的jiar包：

下面是一段對 配置文件操作的代碼：

package unweb.xml;

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

import java.io.FileWriter;
import java.io.IOException;
import java.util.Iterator;

/**
 * Created by Administrator on 2016/8/17.
 * 使用dom4j 操作xml 文件
 */
public class Dom4jTest {
    private static Document doc = null; //文檔對象

    public static void main(String[] args) {
        initXmlDocumentObject(); //初始化
        Element ele = doc.getRootElement();
        getAllXmlInfo(ele);
    }

    /*獲取文檔對象*/
    public static void initXmlDocumentObject() {
        try {
            SAXReader saxReader = new SAXReader();
            doc = saxReader.read("src/xmlTest.xml");
        } catch (DocumentException e) {
            e.printStackTrace();
        }
    }

    /*獲取根目錄並且遍歷根目錄下的子元素*/
    public static void rootTest() {
        Element ele = doc.getRootElement(); //獲取根元素
        for (Iterator i = ele.elementIterator(); i.hasNext(); ) {
            Element e = (Element) i.next(); //第一級子元素
            System.out.println(e.getName() + ", " + e.attributeValue("name"));
            for (Iterator j = e.elementIterator(); j.hasNext(); ) {
                Element e2 = (Element) j.next(); //第二級子元素
                System.out.println("\t" + e2.getText());
            }
        }
    }

    /*遍歷整個 xml 文件*/
    public static void getAllXmlInfo(Element ele){
        for(Iterator i = ele.elementIterator(); i.hasNext(); ){
            Element e1 = (Element) i.next();
            System.out.println("名稱：" + e1.getName() + ", name 屬性："+ e1.attributeValue("name"));
            Iterator i1 = e1.elementIterator();
            if(i1.hasNext()){ //如果元素存在子元素，則遍歷其子元素
                getAllXmlInfo(e1); //遞歸
            }
        }
    }

    /*添加元素*/
    public static void addElement() {
        Element ele = doc.getRootElement(); //獲取根元素
        Element e1 = ele.addElement("room4"); //創建子元素
        ele.addAttribute("name", "room4"); //添加屬性
        Element e2 = e1.addElement("size"); //創建子元素
        e2.addText("noExist"); //添加文本
    }

    /*修改屬性*/
    public static void updateElement() {
        Element ele = doc.getRootElement(); //獲取根元素
        for (Iterator i = ele.elementIterator(); i.hasNext(); ) {
            Element e1 = (Element) i.next();
            if ("3".equals(e1.attributeValue("id"))) {
                //e1.getParent().remove(e1); //刪除子元素操作
                e1.addAttribute("name", "after update");
            }
        }
    }

    /*保存xml*/
    public static void saveXmlFile() {
        String path = "src/newXml.xml";
        OutputFormat of = OutputFormat.createCompactFormat();
        of.setEncoding("utf-8"); //設置編碼格式
        XMLWriter xmlWriter = null;
        try {
            xmlWriter = new XMLWriter(new FileWriter(path), of);
            xmlWriter.write(doc); //寫入文件
            xmlWriter.close(); //關閉流
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}

操作的xml 文件如下：

<?xml version="1.0" encoding="utf-8" ?>
<rooms>
    <room id="1" name="room1">
        <size name="size1">big</size>
        <size name="size2">middle</size>
    </room>
    <room id="2" name="room2">
        <size name="size1">big</size>
        <size name="size2">middle</size>
    </room>
    <room id="3" name="room3">
        <size name="size1">
            <type name="type">double</type>
        </size>
        <size name="size2">small</size>
    </room>
</rooms>

獲取節點下的子元素也可以使用已下方法：

 Element ele = doc.getRootElement();
        for(Object e: ele.elements()){
            Element e2 = (Element) e;
            System.out.println(e2.getName());
        }