dom4j修改,獲取,增加xml中某個元素的屬性值

XML文件：

<?xml version="1.0" encoding="UTF-8"?>

<vrvscript> 
  <item ID="1021" isSelf="n"/>  
  <item ID="1023" isSelf="n"/>  
  <item ID="1003" isSelf="n"/>  
  <item ID="1020" isSelf="n"/>  
  <item ID="1022" isSelf="n"/> 
</vrvscript>

修改屬性值：要把每個item元素的“isSelf”屬性值修改為“y”

// 獲取XML
Document document = XMLUtil.getDocument(xmlPath);
Element root = document.getRootElement();
            
Iterator<?> ruleNodes = root.elementIterator("item");
while (ruleNodes.hasNext()) {
        Element ruleElement = (Element) ruleNodes.next();
        // 修改isSelf的屬性值
       Attribute isSelfAttr = ruleElement.attribute("isSelf");
       isSelfAttr.setValue("n");                
}
writeXml(document, xmlPath.getPath());

    /**
     * 輸出xml文件
     * 
     * @param document
     * @param filePath
     * @throws IOException
     */
    public static void writeXml(Document document, String filePath) throws IOException {
        File xmlFile = new File(filePath);
        XMLWriter writer = null;
        try {
            if (xmlFile.exists())
                xmlFile.delete();
            writer = new XMLWriter(new FileOutputStream(xmlFile), OutputFormat.createPrettyPrint());
            writer.write(document);
            writer.close();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (writer != null)
                writer.close();
        }
    }

獲取屬性值：采用Element類的attributeValue方法

String policyName = root.attributeValue("PolicyName");

給XML元素增加屬性

Element ruleElement = root.addElement("item");
ruleElement.addAttribute("ID", "1101");
ruleElement.addAttribute("isSelf", "y");

一些提供一個dom4j操作XML的工具類：

package com.vrv.paw.utils;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Iterator;
import java.util.Map;

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

/**
 * 操作XML文件的工具類
 * 
 * @author glw
 */
public class XMLUtil {
    /**
     * 得到XML文檔
     * 
     * @param xmlFile
     *            文件名（路徑）
     * @return XML文檔對象
     * @throws DocumentException
     */
    public static Document getDocument(String xmlFile) {
        SAXReader reader = new SAXReader();
        reader.setEncoding("UTF-8");
        File file = new File(xmlFile);
        try {
            if (!file.exists()) {
                return null;
            } else {
                return reader.read(file);
            }
        } catch (DocumentException e) {
            throw new RuntimeException(e + "->指定文件【" + xmlFile + "】讀取錯誤");
        }
    }

    /**
     * 得到XML文檔(編碼格式-gb2312)
     * 
     * @param xmlFile
     *            文件名（路徑）
     * @return XML文檔對象
     * @throws DocumentException
     */
    public static Document getDocument_gb2312(String xmlFile) {
        SAXReader reader = new SAXReader();
        reader.setEncoding("gb2312");
        File file = new File(xmlFile);
        try {
            if (!file.exists()) {
                return null;
            } else {
                return reader.read(file);
            }
        } catch (DocumentException e) {
            throw new RuntimeException(e + "->指定文件【" + xmlFile + "】讀取錯誤");
        }
    }

    public static String getText(Element element) {
        try {
            return element.getTextTrim();
        } catch (Exception e) {
            throw new RuntimeException(e + "->指定【" + element.getName() + "】節點讀取錯誤");
        }

    }

    /**
     * 增加xml文件節點
     * 
     * @param document
     *            xml文檔
     * @param elementName
     *            要增加的元素名稱
     * @param attributeNames
     *            要增加的元素屬性
     * @param attributeValues
     *            要增加的元素屬性值
     */
    public static Document addElementByName(Document document, String elementName, Map<String, String> attrs, String cdata) {
        try {
            Element root = document.getRootElement();
            Element subElement = root.addElement(elementName);
            for (Map.Entry<String, String> attr : attrs.entrySet()) {
                subElement.addAttribute(attr.getKey(), attr.getValue());
            }
            subElement.addCDATA(cdata);
        } catch (Exception e) {
            throw new RuntimeException(e + "->指定的【" + elementName + "】節點增加出現錯誤");
        }
        return document;
    }

    /**
     * 刪除xml文件節點
     */
    @SuppressWarnings("unchecked")
    public static Document deleteElementByName(Document document, String elementName) {
        Element root = document.getRootElement();
        Iterator<Object> iterator = root.elementIterator("file");
        while (iterator.hasNext()) {
            Element element = (Element) iterator.next();
            // 根據屬性名獲取屬性值
            Attribute attribute = element.attribute("name");
            if (attribute.getValue().equals(elementName)) {
                root.remove(element);
                document.setRootElement(root);
                break;
            }
        }
        return document;
    }

    /**
     * 輸出xml文件
     * 
     * @param document
     * @param filePath
     * @throws IOException
     */
    public static void writeXml(Document document, String filePath) throws IOException {
        File xmlFile = new File(filePath);
        XMLWriter writer = null;
        try {
            if (xmlFile.exists())
                xmlFile.delete();
            writer = new XMLWriter(new FileOutputStream(xmlFile), OutputFormat.createPrettyPrint());
            writer.write(document);
            writer.close();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (writer != null)
                writer.close();
        }
    }

    /**
     * 創建Document及根節點
     * 
     * @param rootName
     * @param attributeName
     * @param attributeVaule
     * @return
     */
    public static Document createDocument(String rootName, String attributeName, String attributeVaule) {
        Document document = null;
        try {
            document = DocumentHelper.createDocument();
            Element root = document.addElement(rootName);
            root.addAttribute(attributeName, attributeVaule);
        } catch (Exception e) {
            throw new RuntimeException(e + "->創建的【" + rootName + "】根節點出現錯誤");
        }
        return document;
    }

    /**
     * 刪除xml文件節點
     */
    @SuppressWarnings("unchecked")
    public static Document deleteElementAddressByName(Document document, String elementName) {
        Element root = document.getRootElement();
        Iterator<Object> iterator = root.elementIterator("address");
        while (iterator.hasNext()) {
            Element element = (Element) iterator.next();
            // 根據屬性名獲取屬性值
            Attribute attribute = element.attribute("name");
            if (attribute.getValue().equals(elementName)) {
                root.remove(element);
                document.setRootElement(root);
                break;
            }
        }
        return document;
    }
    
    /**
     *    刪除屬性等於某個值的元素
     *    @param document  XML文檔
     *    @param xpath xpath路徑表達式
     *    @param attrName 屬性名
     *    @param attrValue 屬性值
     *    @return      
     */
    @SuppressWarnings("unchecked")
    public static Document deleteElementByAttribute(Document document, String xpath, String attrName, String attrValue) {
        Iterator<Object> iterator = document.selectNodes(xpath).iterator();
        while (iterator.hasNext()) {
            Element element = (Element) iterator.next();
            Element parentElement = element.getParent();
            // 根據屬性名獲取屬性值
            Attribute attribute = element.attribute(attrName);
            if (attribute.getValue().equals(attrValue)) {
                parentElement.remove(element);
            }
        }
        return document;
    }
}