使用Xml文档进行数据的保存的学生成绩管理系统

package cn.itcast.dao;

import java.io.FileOutputStream;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
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 cn.itcast.bean.Student;

public class StudentDao {

public static void add(Student stu) throws Exception{
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/Exam.xml");

Element e1 = (Element) document.getElementsByTagName("human").item(0);

Element e2 = (Element) document.createElement("student");
e1.appendChild(e2);

Element e21 = (Element) document.createElement("usrname");
e21.setTextContent(stu.getUsrname());

Element e22 = (Element) document.createElement("ticketNum");
e22.setTextContent(stu.getTicketNum());

Element e23 = (Element) document.createElement("idNum");
e23.setTextContent(stu.getIdNum());

Element e24 = (Element) document.createElement("location");
e24.setTextContent(stu.getLocation());

Element e25 = (Element) document.createElement("gradeNum");
e25.setTextContent(stu.getGradeNum());

e2.appendChild(e21);
e2.appendChild(e22);
e2.appendChild(e23);
e2.appendChild(e24);
e2.appendChild(e25);

TransformerFactory ttfactory = TransformerFactory.newInstance();
Transformer tf = ttfactory.newTransformer();
tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/Exam.xml")));

}

public static void delete(String usrname) throws Exception{
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/Exam.xml");

NodeList list = document.getElementsByTagName("usrname");
for(int i=0;i<list.getLength();i++){
String content = list.item(i).getTextContent();
if(content.equals(usrname)){
list.item(i).getParentNode().getParentNode().removeChild(list.item(i).getParentNode());
}
}

TransformerFactory ttfactory = TransformerFactory.newInstance();
Transformer tf = ttfactory.newTransformer();
tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/Exam.xml")));
}

public static void read(String ticketNum) throws Exception{
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/Exam.xml");

NodeList list = document.getElementsByTagName("ticketNum");
for(int i=0;i<list.getLength();i++){
String num = list.item(i).getTextContent();
if(num.equals(ticketNum)){
Node root = list.item(i).getParentNode();
list(root);
}
}
}

private static void list(Node root) {
NodeList child = root.getChildNodes();
for(int i=0;i<child.getLength();i++){
Node node = child.item(i);
System.out.println(node.getNodeName()+":"+node.getTextContent());
}
}

}