dom4j的简单使用案例

引入dom4j的jar包：
dom4j-1.6.1.jar和jaxen-1.1-beta-6.jar

测试类：

package com.ming.xmlParse;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.OutputStream;import java.net.URL;import java.util.Iterator;import java.util.List;import javax.xml.transform.Transformer;import javax.xml.transform.TransformerFactory;import javax.xml.transform.stream.StreamSource;import org.dom4j.Attribute;import org.dom4j.Document;import org.dom4j.DocumentException;import org.dom4j.DocumentHelper;import org.dom4j.Element;import org.dom4j.Node;import org.dom4j.io.DocumentResult;import org.dom4j.io.DocumentSource;import org.dom4j.io.OutputFormat;import org.dom4j.io.SAXReader;import org.dom4j.io.XMLWriter;import org.junit.Test;import org.xml.sax.SAXException;/* * xml文档内容： *  *          <?xml version="1.0" encoding="UTF-8"?>  *          <!DOCTYPE catalog SYSTEM "file://c:/Dtds/catalog.dtd"> *          <catalog>  *              <!--An XML Catalog-->  *              <?target instruction?> *              <journal title="XML Zone" publisher="IBM developerWorks"> *                  <article level="Intermediate" date="December-2001">  *                      <title>Java configuration with XML Schema</title>  *                      <author> *                          <firstname>Marcello</firstname> *                          <lastname>Vitaletti</lastname>  *                      </author> *                  </article>  *              </journal>  *          </catalog> *//** * @author Alexia *  *         Dom4j 解析XML文档 */public class Dom4jDemo implements XmlDocument {    /**     * 简单使用dom4j解析，不使用xpath     */    public void parserXml(String fileName) {        try {            File file = new File(fileName);            Document document = parse(file);            // 获取根元素            Element root = document.getRootElement();            // 遍历元素的子元素（只有一层）            for (Iterator<Element> i = root.elementIterator(); i.hasNext();) {                Element element = i.next();                for (Iterator<Element> j = element.elementIterator(); j.hasNext();) {                    Element element1 = j.next();                    String name = element1.getName();                    String text = element1.getTextTrim();                    System.err.println("--" + name + ":" + text + "--");                }            }            // 遍历元素的子元素（指定元素名称）（只有一层）            for (Iterator<Element> i = root.elementIterator("journal"); i.hasNext();) {                Element element = i.next();                String name = element.getName();                String text = element.getTextTrim();                System.err.println("--" + name + ":" + text + "--");            }            // 遍历元素的属性            for (Iterator<Attribute> i = root.attributeIterator(); i.hasNext();) {                Attribute attribute = i.next();                String name = attribute.getName();                String value = attribute.getValue();                System.err.println("--" + name + ":" + value + "--");            }            // 递归遍历根元素下的所有子节点，并进行行相应的操作            treeWalk(root);        } catch (DocumentException e) {            e.printStackTrace();        } catch (SAXException e) {            e.printStackTrace();        }    }    /**     *      * @Title: treeWalk     * @Description: TODO(递归遍历元素下的所有子节点，并进行行相应的操作)     * @return void 返回类型     * @param element     */    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 {            }        }    }    /**     *      * @Title: createDoc     * @Description: TODO(使用dom4j创建一个document)     * @return void 返回类型     */    @Test    public Document createDoc() {        // 创建文档        Document document = DocumentHelper.createDocument();        // 添加子元素        Element catalogElement = document.addElement("catalog");        // 添加注释        catalogElement.addComment("An XML catalog");        // 添加处理指令        catalogElement.addProcessingInstruction("target", "text");        Element journalElement = catalogElement.addElement("journal");        // 添加属性        journalElement.addAttribute("title", "XML Zone");        journalElement.addAttribute("publisher", "IBM developerWorks");        Element articleElement = journalElement.addElement("article");        articleElement.addAttribute("level", "Intermediate");        articleElement.addAttribute("date", "December-2001");        Element titleElement = articleElement.addElement("title");        // 设置文本        titleElement.setText("Java configuration with XML Schema");        Element authorElement = articleElement.addElement("author");        Element firstnameElement = authorElement.addElement("firstname");        firstnameElement.setText("Marcello");        Element lastnameElement = authorElement.addElement("lastname");        lastnameElement.setText("Vitaletti");        // 添加文档类型说明        document.addDocType("catalog", null, "file://c:/Dtds/catalog.dtd");        return document;    }    /**     *      * @Title: parse     * @Description: TODO(用SAXReader解析为document)     * @return Document 返回类型     * @param url     * @return     * @throws DocumentException     * @throws SAXException     */    public Document parse(URL url) throws DocumentException, SAXException {        SAXReader saxReader = new SAXReader();        // 忽略<!DOCTYPE>等元素中的dtd校验（如果校验不成功会直接抛出异常）        saxReader.setValidation(false);        saxReader.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);        Document document = saxReader.read(url);        return document;    }    /**     *      * @Title: parse     * @Description: TODO(用SAXReader解析为document)     * @return Document 返回类型     * @param url     * @return     * @throws SAXException     * @throws DocumentException     */    public Document parse(File file) throws SAXException, DocumentException {        SAXReader saxReader = new SAXReader();        // 忽略<!DOCTYPE>等元素中的dtd校验（如果校验不成功会直接抛出异常）        saxReader.setValidation(false);        saxReader.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);        Document document = saxReader.read(file);        return document;    }    /**     *      * @Title: updateDoc     * @Description: TODO(测试修改文档，使用SAXReader和xpath) 节点的增、删、改、查     * @return void 返回类型     * @param filename     * @throws DocumentException     * @throws SAXException     */    public void updateDoc(String filename) throws DocumentException, SAXException {        File file = new File(filename);        // 解析为document        Document document = parse(file);        // xpath选择文档中article元素中获得 level属性值是“Intermediate”的元素节点        List<Element> list = document.selectNodes("//article[@level='Intermediate']");        Iterator<Element> iterator = list.iterator();        while (iterator.hasNext()) {            Element next = iterator.next();            // next.setAttributeValue("level",            // "Introductory");//过时用addAttribute替代            // 修改属性值            next.addAttribute("level", "Introductory");            // 添加color属性            next.addAttribute("color", "red");        }        // 选取所有的lastname元素节点        List<Element> list2 = document.selectNodes("//lastname");        Iterator<Element> iterator2 = list2.iterator();        while (iterator2.hasNext()) {            Element next = iterator2.next();            String textTrim = next.getTextTrim();            if ("Vitaletti".equals(textTrim)) {                // 删除节点                next.getParent().remove(next);            }        }        // 输出到控制台        writeDoc(document);    }    /**     *      * @Title: writeDoc     * @Description: TODO(将document格式化输出到指定的文件中)     * @return void 返回类型     * @param document     * @param filename     */    public void writeDoc(Document document, String filename) {        OutputStream outputStream = null;        XMLWriter xmlWriter = null;        try {            // 输出流            outputStream = new FileOutputStream(filename);            // 输出格式            // 设置文件编码            OutputFormat xmlFormat = new OutputFormat();            xmlFormat.setEncoding("UTF-8");            // 设置换行            xmlFormat.setNewlines(true);            // 生成缩进            xmlFormat.setIndent(true);            // 使用4个空格进行缩进, 可以兼容文本编辑器            xmlFormat.setIndent("    ");            xmlWriter = new XMLWriter(outputStream, xmlFormat);            xmlWriter.write(document);        } catch (IOException e) {            e.printStackTrace();        } finally {            try {                xmlWriter.close();                outputStream.close();            } catch (IOException e) {                e.printStackTrace();            }        }    }    /**     *      * @Title: writeDoc     * @Description: TODO(将document格式化输出控制台)     * @return void 返回类型     * @param document     */    public void writeDoc(Document document) {        XMLWriter xmlWriter = null;        try {            // 输出格式            // 设置文件编码            OutputFormat xmlFormat = new OutputFormat();            xmlFormat.setEncoding("UTF-8");            // 设置换行            xmlFormat.setNewlines(true);            // 生成缩进            xmlFormat.setIndent(true);            // 使用4个空格进行缩进, 可以兼容文本编辑器            xmlFormat.setIndent("    ");            xmlWriter = new XMLWriter(xmlFormat);            xmlWriter.write(document);        } catch (IOException e) {            e.printStackTrace();        } finally {            try {                xmlWriter.close();            } catch (IOException e) {                e.printStackTrace();            }        }    }    /**     *      * @Title: docToXml     * @Description: TODO(文档转为xml字符串)     * @return String 返回类型     * @param document     * @return     */    public String docToXml(Document document) {        return document.asXML();    }    /**     *      * @Title: xmlToDocument     * @Description: TODO(xml字符串转为document)     * @return Document 返回类型     * @param xml     * @return     * @throws DocumentException     */    public Document xmlToDocument(String xml) throws DocumentException {        return DocumentHelper.parseText(xml);    }    /**     *     * @Title: styleDocument    * @Description: TODO(格式转换（未测试，不清楚功能）)    * @return Document    返回类型    * @param document    * @param stylesheet    * @return    * @throws Exception     */    public Document styleDocument(Document document, String stylesheet) throws Exception {        // load the transformer using JAXP        TransformerFactory factory = TransformerFactory.newInstance();        Transformer transformer = factory.newTransformer(new StreamSource(stylesheet));        // now lets style the given document        DocumentSource source = new DocumentSource(document);        DocumentResult result = new DocumentResult();        transformer.transform(source, result);        // return the transformed document        Document transformedDoc = result.getDocument();        return transformedDoc;    }    public static void main(String[] args) {        Dom4jDemo dom4jDemo = new Dom4jDemo();        // 将document写入xml文件中        dom4jDemo.writeDoc(dom4jDemo.createDoc(), "C:\\Users\\Administrator\\Desktop\\catalog.xml");        // 测试增、删、改、查docuemnt中的节点，使用xpath        try {            dom4jDemo.updateDoc("C:\\Users\\Administrator\\Desktop\\catalog.xml");        } catch (Exception e) {            e.printStackTrace();        }        // 使用Iterators遍历节点        dom4jDemo.parserXml("C:\\Users\\Administrator\\Desktop\\catalog.xml");    }}