xml解析（超全）---（五）

?StringBuffer sb=new StringBuffer("<?xml version=\"1.0\" encoding=\"gb2312\"?>");
??sb.append("<users>");
??sb.append("<user id=\"1\">");
??sb.append("<name>龙准</name>");
??sb.append("<age>25</age>");
??sb.append("</user>");
??sb.append("<user id=\"2\">");
??sb.append("<name>廖丽</name>");
??sb.append("<age>21</age>");
??sb.append("</user>");
??sb.append("</users>");
??Document doc=null;
??SAXBuilder builder=new SAXBuilder();
??//为文档增加dtd验证
???????? //Builder.setFeature(“http://xml.org/sax/features/validation”;,ture);
??//为文档增加schema验证
?? //Builder.setFeature(“http://apache.org/xml/features/validation/schema”;,true);
?//导入schema文件
?Builder.setPropertity(“http://apache.org/xml/properties/schema/external-noNamespaceSchemaLocation”;,schema)
??try {
???doc=builder.build(new StringReader(sb.toString()));

???//得到根节点
???Element element=doc.getRootElement();
???//得到所有节点
???List list=element.getChildren();
???
???System.out.println("某班共有"+list.size()+"个学生");
???
???for(Iterator it=list.iterator();it.hasNext();){
????Element user=(Element)it.next();
????String id=user.getAttributeValue("id");
????String name=user.getChildText("name");
????String age=user.getChildText("age");
????
????System.out.println("学生"+id+"? ");
????System.out.println("姓名："+name+"?? 年龄："+age);
????
???}
???
??} catch (JDOMException e) {
???e.printStackTrace();
??} catch (IOException e) {
???e.printStackTrace();
??}
输出结果：
某班共有2个学生
学生1?
姓名：龙准?? 年龄：25
学生2?
姓名：廖丽?? 年龄：21

新增节点：

//新增节点
???Element newElement=new Element("user");
???newElement.setAttribute("id","3");
???newElement.addContent(new Element("name").setText("嘻哈"));
???newElement.addContent(new Element("age").setText("23"));
????
???element.addContent(newElement);
???//删除节点
???list.remove(2);???? //删除第三个子元素
???
???element.removeChildren("user");? //删除名为user的子元素

//生成xml文档
??Element root=new Element("student-info");
??Element stu=new Element("student");
??stu.addContent(new Element("number").setText("001"));
??stu.addContent(new Element("name").setText("中国"));
??stu.addContent(new Element("age").setText("60"));
??root.addContent(stu);
??Document doc=new Document(root);
??
??Format format=Format.getCompactFormat();
??format.setEncoding("gb2312");
??format.setIndent("?? ");//设置xml文件的缩进为4个空格
??XMLOutputter op=new XMLOutputter(format);
??
??try {
???op.output(doc, new FileOutputStream("d://student22.xml"));
??} catch (FileNotFoundException e) {
???e.printStackTrace();
??} catch (IOException e) {
???e.printStackTrace();
??}
//生成xml文档2
Document document=new Document();
??//为xml文档添加处理指令
??ProcessingInstruction pi=new ProcessingInstruction("xml-stylesheet","type='text/xsl' href=test.xsl" );
??document.addContent(pi);
??//添加名称空间
??Namespace namespace=Namespace.getNamespace("http://www.apache.org");
??Namespace namespace2=Namespace.getNamespace("other", "http://www.w3c.org");
??//创建带有名称空间的根元素
??Element root1=new Element("student-info",namespace);
??
??root1.addNamespaceDeclaration(namespace2);
??
??Element stu=new Element("student");
??stu.setAttribute("id","001");
??stu.addContent(new Text("第一个学生"));
??stu.addContent(new Element("name").setText("ss"));
??stu.addContent(new Element("age").setText("24"));
??
??Element stu2=new Element("student");
??stu2.setAttribute("id","002");
??stu2.addContent(new Text("第二个学生"));
??stu2.addContent(new Element("name").setText("dd"));
??stu2.addContent(new Element("age").setText("22"));
??
??root1.addContent(stu);
??root1.addContent(stu2);
??
??document.addContent(root1);
??
??Format fm=Format.getCompactFormat();
??fm.setEncoding("gb2312");
??fm.setIndent("??? ");
??XMLOutputter xmlout=new XMLOutputter(fm);
??
??try {
???xmlout.output(document, new FileOutputStream("d://3.xml"));
??} catch (FileNotFoundException e) {
???e.printStackTrace();
??} catch (IOException e) {
???e.printStackTrace();
??}

JDOM+Xpath读取，修改xml
SAXBuilder builder=new SAXBuilder();
??try {
???Document doc=builder.build(new File("d://user2.xml"));
???
???XPath userPath=XPath.newInstance("//user");
???List userList=userPath.selectNodes(doc);
???System.out.println("某班共有"+userList.size()+"个学生");
???for(Iterator it=userList.iterator();it.hasNext();){
????Element userElement=(Element)it.next();
????String id=userElement.getAttributeValue("id");
????String name=userElement.getChildText("name");
????//修改龙准的年龄
????if(name.equals("龙准")){
?????userElement.getChild("age").setText("26");
????}
????String age=userElement.getChild("age").getTextTrim();
????System.out.println("学生? "+id);
????System.out.println("姓名："+name+"? 年龄："+age);
???}
???//保存到硬盘
???Format fm=Format.getCompactFormat();
???fm.setEncoding("gb2312");
???fm.setIndent("??? ");
???XMLOutputter out=new XMLOutputter(fm);
???out.output(doc, new FileOutputStream("d://user2.xml"));
???
??} catch (JDOMException e) {
???e.printStackTrace();
??} catch (IOException e) {
???e.printStackTrace();
??}