xml 三种解析方式dom,sax,dom4j

package dom; import javax.xml.parsers.*; import org.w3c.dom.*; import java.io.*; import org.apache.crimson.tree.XmlDocument; import org.w3c.dom.NodeList; public class Dom_xml { /** * 遍历xml文档 * */ public static void queryXml(){ try{ //得到DOM解析器的工厂实例 DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance(); //从DOM工厂中获得DOM解析器 DocumentBuilder dbBuilder = dbFactory.newDocumentBuilder(); //把要解析的xml文档读入DOM解析器 Document doc = dbBuilder.parse("D:\\xmlFile.xml"); System.out.println("处理该文档的DomImplementation对象 = "+ doc.getImplementation()); //得到文档名称为Student的元素的节点列表 NodeList nList = doc.getElementsByTagName("Student"); //遍历该集合，显示结合中的元素及其子元素的名字 for(int i = 0; i< nList.getLength() ; i ++){ Element node = (Element)nList.item(i); System.out.println("Name: "+ node.getElementsByTagName("Name").item(0).getFirstChild().getNodeValue()); System.out.println("Num: "+ node.getElementsByTagName("Num").item(0).getFirstChild().getNodeValue()); System.out.println("Classes: "+ node.getElementsByTagName("Classes").item(0).getFirstChild().getNodeValue()); System.out.println("Address: "+ node.getElementsByTagName("Address").item(0).getFirstChild().getNodeValue()); System.out.println("Tel: "+ node.getElementsByTagName("Tel").item(0).getFirstChild().getNodeValue()); } }catch (Exception e) { e.printStackTrace(); } } /** * 向已存在的xml文件中插入元素 * */ public static void insertXml(){ Element school = null; Element student = null; Element name = null; Element num = null; Element classes = null; Element address = null; Element tel = null; try{ //得到DOM解析器的工厂实例 DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance(); //从DOM工厂中获得DOM解析器 DocumentBuilder dbBuilder = dbFactory.newDocumentBuilder(); //把要解析的xml文档读入DOM解析器 Document doc = dbBuilder.parse("D:\\xmlFile.xml"); //得到文档名称为Student的元素的节点列表 NodeList nList = doc.getElementsByTagName("School"); school = (Element)nList.item(0); //创建名称为Student的元素 student = doc.createElement("Student"); //设置元素Student的属性值为231 student.setAttribute("examId", "23"); //创建名称为Name的元素 name = doc.createElement("Name"); //创建名称为 香香 的文本节点并作为子节点添加到name元素中 name.appendChild(doc.createTextNode("missxiang")); //将name子元素添加到student中 student.appendChild(name); /** * 下面的元素依次加入即可 * */ num = doc.createElement("Num"); num.appendChild(doc.createTextNode("1006010066")); student.appendChild(num); classes = doc.createElement("Classes"); classes.appendChild(doc.createTextNode("tesat5")); student.appendChild(classes); address = doc.createElement("Address"); address.appendChild(doc.createTextNode("wenzhou")); student.appendChild(address); tel = doc.createElement("Tel"); tel.appendChild(doc.createTextNode("123890")); student.appendChild(tel); //将student作为子元素添加到树的根节点school school.appendChild(student); //将内存中的文档通过文件流生成insertSchool.xml,XmlDocument位于crison.jar下 ((XmlDocument)doc).write(new FileOutputStream("D:\\xmlFile_insert.xml")); System.out.println("success"); }catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } /** * 创建xml文档 * */ public static void createDom(){ Document doc; Element school,student; Element name = null; Element num = null; Element classes = null; Element address = null; Element tel = null; try{ //得到DOM解析器的工厂实例 DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance(); //从DOM工厂中获得DOM解析器 DocumentBuilder dbBuilder = dbFactory.newDocumentBuilder(); //创建文档树模型对象 doc = dbBuilder.newDocument(); if(doc != null){ //创建school元素 school = doc.createElement("School"); //创建student元素 student = doc.createElement("Student"); //设置元素Student的属性值为231 student.setAttribute("examId", "23"); //创建名称为Name的元素 name = doc.createElement("Name"); //创建名称为 香香 的文本节点并作为子节点添加到name元素中 name.appendChild(doc.createTextNode("name_new")); //将name子元素添加到student中 student.appendChild(name); /** * 下面的元素依次加入即可 * */ num = doc.createElement("Num"); num.appendChild(doc.createTextNode("1006010066")); student.appendChild(num); classes = doc.createElement("Classes"); classes.appendChild(doc.createTextNode("new5")); student.appendChild(classes); address = doc.createElement("Address"); address.appendChild(doc.createTextNode("wuxi")); student.appendChild(address); tel = doc.createElement("Tel"); tel.appendChild(doc.createTextNode("123890")); student.appendChild(tel); //将student作为子元素添加到树的根节点school school.appendChild(student); //添加到文档树中 doc.appendChild(school); //将内存中的文档通过文件流生成insertSchool.xml,XmlDocument位于crison.jar下 ((XmlDocument)doc).write(new FileOutputStream("D:\\xmlFile_new.xml")); System.out.println("success"); } }catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } public static void main(String[] args) { queryXml(); insertXml(); createDom(); } }