Dom4j学习-1

DOM4J是dom4j.org出品的一个开源XML解析包。Dom4j是一个易用的、开源的库，用于XML，XPath和XSLT。它应用于Java平台，采用了Java集合框架并完全支持DOM，SAX和JAXP。
DOM4J下载jar包：http://downloads.sourceforge.net/dom4j/dom4j-1.6.1.jar
JAXEN（对XPath的支持）：http://dist.codehaus.org/jaxen/distributions/jaxen-1.1.1.zip

DOM4J主要接口都在org.dom4j这个包里定义。

结构如下：




-Node为所有的dom4j中XML节点定义了多态行为；

-Branch为能够包含子节点的节点如XML元素(Element)和文档(Docuemnts)定义了一个公共的行为；
|-Element 定义XML 元素；
|-Document定义了XML文档；

-DocumentType 定义XML DOCTYPE声明；
-Entity定义 XML entity；
-Attribute定义了XML的属性；
-ProcessingInstruction 定义 XML 处理指令；

-CharacterData是一个标识借口，标识基于字符的节点。如CDATA，Comment, Text；
|- CDATA 定义了XML CDATA 区域；
|- Text 定义XML 文本节点；
|- Comment 定义了XML注释的行为；

<?xml version="1.0" encoding="UTF-8"?> <book id='history' value="cn.txt.History">   <address id='22'>100010</address>    <title id='33'>java tools</title>    <file id='44'>c:\file\</file>  </book>

package test.Dom4j;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 javax.xml.parsers.SAXParserFactory;import javax.xml.parsers.SAXParser;import org.dom4j.Document;import org.dom4j.DocumentException;import org.dom4j.io.SAXReader;import org.dom4j.io.SAXValidator;import org.dom4j.io.XMLWriter;import org.dom4j.io.OutputFormat;import org.dom4j.Element;import org.dom4j.Attribute;import org.dom4j.util.XMLErrorHandler;/** * @projectName：Test * @packageName: test.Dom4j * @ClassName  : Dom4jTest * @createBy   ：Text * @createDate ：2014-5-30 下午04:13:04 * @version    : *  */public class Dom4jTest {// 读取文件转换成Document对象public Document parseFile2Document(String filename) throws DocumentException {//SAXReader用于读取文件SAXReader reader = new SAXReader();Document document = reader.read(filename);return document;}    @SuppressWarnings("all")public void parseContent(Document document){Element root = document.getRootElement();// 打印root结点的名称System.out.println("Root Element:" + root.getName());// 打印root结点中属性的名字for (Iterator i = root.attributeIterator(); i.hasNext();) {Attribute attribute = (Attribute) i.next();System.out.println(attribute.getName() + ":" + attribute.getValue());}// 打印根元素的所有子元素的名称和值for (Iterator i = root.elementIterator(); i.hasNext();) {Element element = (Element) i.next();System.out.println(element.getName() + ":" + element.getText());if (element.getName().equals("address")) {element.setText("西安市长安区"); // 修改元素的Text}   //枚举属性           for (Iterator ia = element.attributeIterator(); ia.hasNext();) {              Attribute attribute = (Attribute) ia.next();              System.out.println(attribute.getName() + ":"                     + attribute.getData());           }}// 修改后进行打印for (Iterator i = root.elementIterator(); i.hasNext();) {Element element = (Element) i.next();System.out.println(element.getName() + ":" + element.getText());}// 把修改后的文件保存下来OutputFormat format = null;XMLWriter xmlwriter = null;// 进行格式化format = OutputFormat.createPrettyPrint();// 设定编码format.setEncoding("UTF-8");try {xmlwriter = new XMLWriter(new FileOutputStream("test.xml"), format);xmlwriter.write(document);xmlwriter.flush();xmlwriter.close();} catch (UnsupportedEncodingException e) {e.printStackTrace();} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}// 通过xsd校验xmlpublic void validateXMLByXSD() {String xmlName = "src\\用户基本信息.xml";String xsdName = "src\\用户基本信息.xsd";try {// 创建默认的xml错误处理器XMLErrorHandler errorHandler = new XMLErrorHandler();// 获取基于SAX的解析器的实例SAXParserFactory factory = SAXParserFactory.newInstance();// 解析器在解析时验证xml内容factory.setValidating(true);// 使用当前配置的工厂参数创建SAXParser的一个新实例SAXParser parser = factory.newSAXParser();// 创建一个读取工具SAXReader xmlReader = new SAXReader();// 获取要校验xml文档实例Document xmlDocument = xmlReader.read(new File(xmlName));// 设置 XMLReader 的基础实现中的特定属性parser.setProperty("http://java.sun.com/xml/jaxp/properties/schemaLanguage","http://www.w3.org/2001/XMLSchema");parser.setProperty("http://java.sun.com/xml/jaxp/properties/schemaSource","file:" + xsdName);// 创建一个SAXValidator校验工具,并设置校验器的属性SAXValidator validator = new SAXValidator(parser.getXMLReader());// 设置校验工具的错误处理器，当发生错误时，可以从处理器对象中得到错误信息validator.setErrorHandler(errorHandler);// 校验validator.validate(xmlDocument);XMLWriter writer = new XMLWriter(OutputFormat.createPrettyPrint());// 如果错误信息不为空，说明校验失败，打印错误信息if (errorHandler.getErrors().hasContent()) {System.out.println("XML文件通过XSD文件校验失败!");writer.write(errorHandler.getErrors());} else {System.out.println("XML文件通过XSD文件校验成功!");}} catch (Exception e) {System.out.println("xml文件" + xmlName + "通过xsd文件：" + xsdName+ "校验失败!原因是：" + e.getMessage());e.printStackTrace();}}public static void main(String[] args) throws DocumentException,IOException {Dom4jTest read = new Dom4jTest();Document document = read.parseFile2Document("book.xml");read.parseContent(document);}}

import java.io.IOException;import java.util.Collections;import java.util.HashMap;import java.util.Iterator;import java.util.List;import java.util.Map;import org.dom4j.Document;import org.dom4j.DocumentException;import org.dom4j.DocumentHelper;import org.dom4j.Element;import org.dom4j.Node;import org.dom4j.io.SAXReader;/** * @author:LWX * @TODO:XML操作工具类 */public class XmlUtil {/** * @author:LWX * @TODO:字符串转换成XML对象 */public static Document getXMLFromString(String xmlStr) throws Exception {Document document = DocumentHelper.parseText(xmlStr);return document;}/** * @author:LWX * @TODO:XML对象转换成字符串 */public static String getStringFromXML(Document document) {return document.asXML();}/** * @author:LWX * @TODO:读取文件转换成Document对象 */public static Document getDocumentFromFile(String filename)throws DocumentException {SAXReader reader = new SAXReader();Document document = reader.read(filename);return document;}/** * @author:LWX * @TODO:获取根节点 */public static Element getRootElement(Document document) {return document == null ? null : document.getRootElement();}/** * @author:LWX * @TODO:根据节点名获得子节点对象 */public static Element getChildElementByName(Element parentElement,String elementName) {return parentElement == null ? null : parentElement.element(elementName);}/** * @author:LWX * @TODO:获得节点的值 */public static String getElementText(Element element) {return element == null ? null : element.getText();}/** * @author:LWX * @TODO:获得某个节点的属性值 */public static String getAttributeValue(Element element, String attributeName) {return element == null ? null : element.attribute(attributeName).getValue();}/** * @author:LWX * @TODO:添加一个节点 */public static Element addElement(Element parentElement, String elementName,Map<String, String> attributeMap) {if (parentElement == null) {return null;}Element newElement = parentElement.addElement(elementName);for (String key : attributeMap.keySet()) {newElement.addAttribute(key, attributeMap.get(key));}return parentElement;}/** * @author:LWX * @TODO:删除对应节点 */@SuppressWarnings("all")public static void removeElement(Element parentElement,String attributeName, String attributeValue) {Element resultElement = null;if (parentElement != null) {for (Iterator i = parentElement.elementIterator(); i.hasNext();) {Element element = (Element) i.next();if (attributeValue != null&& attributeValue.equals(element.attributeValue(attributeName))) {resultElement = element;break;}}parentElement.remove(resultElement);}}/** * @author:LWX * @TODO:更新属性信息 */@SuppressWarnings("all")public static void updateElement(Element element, String attributeName,String attributeValue) {if (element != null) {element.attribute(attributeName).setValue(attributeValue);}}/** * @author:LWX * @TODO:通过属性值定位Node获得节点对象 节点和参数格式 /report/columns, *                         column[@colCode='DEPTNAME'] */@SuppressWarnings("all")public static Element getElementByNode(Document document, String nodeName,String attributeName) {Element element = null;Node root = document.selectSingleNode(nodeName);List list = root.selectNodes(attributeName);for (Object obj : list) {element = (Element) obj;break;}return element;}/** * @author:LWX * @TODO:根据属性名的值进行升序或降序 nodeName格式 /report/columns attributeName格式@order *  */@SuppressWarnings("all")public static List<Element> getElementsByOrder(Document document,String nodeName, String attributeName, boolean isIncr) {List<Element> nodes = document.selectNodes(nodeName, attributeName);if (!isIncr) {Collections.reverse(nodes);}return nodes;}/** * @author:LWX * @TODO:通过节点名获得节点对象 */@SuppressWarnings("all")public static Element getElementByNodeName(Document document,String nodeName) {List<Element> nodes = document.selectNodes(nodeName);return nodes == null && nodes.size() <= 0 ? null : nodes.get(0);}public static void main(String[] args) throws Exception, IOException {Document document = XmlUtil.getDocumentFromFile("test.xml");Element rootElement = XmlUtil.getRootElement(document);System.out.println(XmlUtil.getElementText(XmlUtil.getChildElementByName(rootElement, "querySql")));Element colElement = XmlUtil.getChildElementByName(rootElement,"columns");System.out.println(XmlUtil.getElementByNode(document,"/report/columns", "column[@colCode='DEPTNAME']").attributeValue("colName"));XmlUtil.removeElement(colElement, "colCode", "DEPTNAME");Map<String, String> map = new HashMap<String, String>();map.put("colCode", "COUNT");map.put("colName", "总数");map.put("colType", "int");map.put("isVisible", "true");map.put("order", "4");XmlUtil.addElement(colElement, "column", map);XmlUtil.updateElement(XmlUtil.getElementByNode(document,"/report/columns", "column[@colCode='DEPTID']"), "isVisible","false");List<Element> nodes = XmlUtil.getElementsByOrder(document,"/report/columns/column", "@order", false);for (Element e : nodes) {System.out.println("colCode : " + e.attributeValue("colCode"));System.out.println("colName : " + e.attributeValue("colName"));}System.out.println(XmlUtil.getElementByNodeName(document,"/report/querySql").getName());System.out.println(XmlUtil.getStringFromXML(document));String initStr = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>";initStr += "<report measureCode=\"mms_user_dept\" measureName=\"部门用户统计\"></report>";document = XmlUtil.getXMLFromString(initStr);XmlUtil.addElement(XmlUtil.getRootElement(document), "columns", map);System.out.println(XmlUtil.getStringFromXML(document));}}

参考：http://zhangjunhd.blog.51cto.com/113473/126310/