生成xml格式文件

要读的xml文件

<?xml version="1.0" encoding="GB2312"?><学生花名册>     <学生 性别 = "男">         <姓名>李华</姓名>         <年龄>14</年龄>     </学生>     <学生 性别 = "男">         <姓名>张三</姓名>         <年龄>16</年龄>      </学生></学生花名册>

import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.InputStream;import java.io.OutputStreamWriter;import java.util.Iterator;import java.util.Vector;import javax.xml.parsers.DocumentBuilder;import javax.xml.parsers.DocumentBuilderFactory;import javax.xml.transform.OutputKeys;import javax.xml.transform.Result;import javax.xml.transform.Source;import javax.xml.transform.Transformer;import javax.xml.transform.TransformerConfigurationException;import javax.xml.transform.TransformerException;import javax.xml.transform.TransformerFactory;import javax.xml.transform.dom.DOMSource;import javax.xml.transform.stream.StreamResult;import org.w3c.dom.Document;import org.w3c.dom.Element;import org.w3c.dom.Node;import org.w3c.dom.NodeList;import org.w3c.dom.Text;public class DomTest {    Vector students_Vector;    private Vector readXMLFile(String file) throws Exception {        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();        DocumentBuilder builder = dbf.newDocumentBuilder();        Document doc = builder.parse(file); // 获取到xml文件        // 下面开始读取        Element root = doc.getDocumentElement(); // 获取根元素        NodeList students = root.getElementsByTagName("学生");        students_Vector = new Vector();        for (int i = 0; i < students.getLength(); i++) {            // 一次取得每一个学生元素            Element ss = (Element) students.item(i);            // 创建一个学生的实例            student stu = new student();            stu.setSex(ss.getAttribute("性别"));            NodeList names = ss.getElementsByTagName("姓名");            Element e = (Element) names.item(0);            Node t = e.getFirstChild();            stu.setName(t.getNodeValue());            NodeList ages = ss.getElementsByTagName("年龄");            e = (Element) ages.item(0);            t = e.getFirstChild();            stu.setAge(Integer.parseInt(t.getNodeValue()));            students_Vector.add(stu);        }        return students_Vector;    }    /**     * 功能：直接提取XML格式字符串中的信息     */    private Vector readXMLString(String xmlStr) throws Exception {        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();        DocumentBuilder builder = dbf.newDocumentBuilder();        InputStream inputStream = new ByteArrayInputStream(xmlStr.getBytes());        Document doc = builder.parse(inputStream); //        // 下面开始读取        Element root = doc.getDocumentElement(); // 获取根元素        NodeList students = root.getElementsByTagName("学生");        students_Vector = new Vector();        for (int i = 0; i < students.getLength(); i++) {            // 一次取得每一个学生元素            Element ss = (Element) students.item(i);            // 创建一个学生的实例            student stu = new student();            stu.setSex(ss.getAttribute("性别"));            NodeList names = ss.getElementsByTagName("姓名");            Element e = (Element) names.item(0);            Node t = e.getFirstChild();            stu.setName(t.getNodeValue());            NodeList ages = ss.getElementsByTagName("年龄");            e = (Element) ages.item(0);            t = e.getFirstChild();            stu.setAge(Integer.parseInt(t.getNodeValue()));            students_Vector.add(stu);        }        return students_Vector;    }    // 将Document内容 写入XML字符串并返回    private String callWriteXmlString(Document doc, String encoding) {        try {            Source source = new DOMSource(doc);            ByteArrayOutputStream outStream = new ByteArrayOutputStream();            OutputStreamWriter write = new OutputStreamWriter(outStream);            Result result = new StreamResult(write);            Transformer xformer = TransformerFactory.newInstance()                    .newTransformer();            xformer.setOutputProperty(OutputKeys.ENCODING, encoding);            xformer.transform(source, result);            return outStream.toString();        } catch (TransformerConfigurationException e) {            e.printStackTrace();            return null;        } catch (TransformerException e) {            e.printStackTrace();            return null;        }    }    /**     * 功能：生成XML格式的字符串     */    public String writeXMLString() {        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();        DocumentBuilder builder = null;        try {            builder = dbf.newDocumentBuilder();        } catch (Exception e) {        }        Document doc = builder.newDocument();        Element root = doc.createElement("学生花名册");        doc.appendChild(root); // 将根元素添加到文档上        // 获取学生信息        for (int i = 0; i < students_Vector.size(); i++) {            student s = (student) students_Vector.get(i);            // 创建一个学生            Element stu = doc.createElement("学生");            stu.setAttribute("性别", s.getSex());            root.appendChild(stu);// 添加属性            // 创建文本姓名节点            Element name = doc.createElement("姓名");            stu.appendChild(name);            Text tname = doc.createTextNode(s.getName());            name.appendChild(tname);            // 创建文本年龄节点            Element age = doc.createElement("年龄");            stu.appendChild(age); // 将age添加到学生节点上            Text tage = doc.createTextNode(String.valueOf(s.getAge()));            age.appendChild(tage); // 将文本节点放在age节点上        }        try {            String result = callWriteXmlString(doc, "gb2312");            return result;        } catch (Exception e) {            e.printStackTrace();            return null;        }    }    /**     * 主函数     */    public static void main(String args[]) {        String str = "xml\\student.xml";        DomTest t = new DomTest();        System.out.println("解析原始XML文件：");        try {            Vector v = t.readXMLFile(str);            Iterator it = v.iterator();            while (it.hasNext()) {                student s = (student) it.next();                System.out.println(s.getName() + "\t" + s.getAge() + "\t"                        + s.getSex());            }        } catch (Exception e) {            e.printStackTrace();        }        String xmlStr = t.writeXMLString();        System.out.println("\n生成的XML字符串：\n" + xmlStr);        try {            Vector v = t.readXMLString(xmlStr);            Iterator it = v.iterator();            System.out.println("\n解析生成的XML字符串：");            while (it.hasNext()) {                student s = (student) it.next();                System.out.println(s.getName() + "\t" + s.getAge() + "\t"                        + s.getSex());            }        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }    }}class student {    private String sex;    private String name;    private int age;    public int getAge() {        return age;    }    public void setAge(int age) {        this.age = age;    }    public void setSex(String s) {        sex = s;    }    public String getSex() {        return sex;    }    public void setName(String n) {        name = n;    }    public String getName() {        return name;    }}

输出：

解析原始XML文件：李华    14    男张三    16    男生成的XML字符串：<?xml version="1.0" encoding="GB2312" standalone="no"?><学生花名册><学生 性别="男"><姓名>李华</姓名><年龄>14</年龄></学生><学生 性别="男"><姓名>张三</姓名><年龄>16</年龄></学生></学生花名册>解析生成的XML字符串：李华    14    男张三    16    男