JAVA高级特性第六章课后作业

1.编写XML文档，具体值自行添加，至少添加两个学员的成绩信息，包括学生id，姓名，学科，分数。

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<scores>
	<student id="10084">
		<name:>张三</name:>
		<course:>JAVA</course:>
		<score:>89</score:>
	</student>
	<student id="10085">
		<name:>黄志豪</name:>
		<course:>JAVA</course:>
		<score:>25</score:>
	</student>
</scores>

2.使用DOM解析简答题1中编写的XML文档，输出所有学员信息，并进行以下操作：删除ID为1的成绩，修改ID为2的成绩为60，添加一个学生的成绩信息（ID为3）。

package kehouzuoye;

import java.io.FileOutputStream;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
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;

public class DOMTest {
	DocumentBuilderFactory dbf = null;
	DocumentBuilder db = null;
	Document doc = null;

	/**
	 * 显示学生信息
	 */
	public void show() {
		dbf = DocumentBuilderFactory.newInstance();
		try {
			db = dbf.newDocumentBuilder();
			doc = db.parse("D:\\Users\\yuanwenjian\\eclipse-workspace\\XML\\src\\kehouzuoye\\Student.xml");
			NodeList nl = doc.getElementsByTagName("student");
			for (int i = 0; i < nl.getLength(); i++) {
				System.out.println("第" + (i + 1) + "位同学的信息:");
				Node nd = nl.item(i);
				Element el = (Element) nl.item(i);
				String str = el.getAttribute("id");
				System.out.println("id:" + str);
				NodeList nls = nd.getChildNodes();
				for (int j = 0; j < nls.getLength(); j++) {
					if (nls.item(j).getNodeType() == Node.ELEMENT_NODE) {
						System.out.println(nls.item(j).getNodeName() + nls.item(j).getFirstChild().getNodeValue());

					}
				}
			}
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

	/**
	 * 保存学生信息
	 */
	public void save() {
		TransformerFactory tff = TransformerFactory.newInstance();
		try {
			Transformer tfo = tff.newTransformer();
			DOMSource ds = new DOMSource(doc);
			StreamResult sr = new StreamResult(new FileOutputStream("NewStudent.xml"));
			tfo.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
			tfo.transform(ds, sr);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * 删除学生信息
	 */
	public void delete() {
		NodeList li = doc.getElementsByTagName("score:");
		Element el = (Element) li.item(0);
		li.item(0).getParentNode().removeChild(el);
		save();
	}

	/**
	 * 修改信息
	 */
	public void amend() {
		NodeList li = doc.getElementsByTagName("score:");
		Element el = (Element) li.item(1);
		el.setTextContent("60");
		save();
	}

	/**
	 * 添加信息
	 */
	public void add() {
		Element el=doc.createElement("student");
		el.setAttribute("id", "10086");
		Element el2=doc.createElement("name:");
		el2.setTextContent("李四");
		Element el3 = doc.createElement("course:");
		el3.setTextContent("JAVA");
		Element el4 = doc.createElement("score:");
		el4.setTextContent("78");
		el.appendChild(el2);
		el.appendChild(el3);
		el.appendChild(el4);
		Element StuElement = (Element)doc.getElementsByTagName("scores").item(0);
		StuElement.appendChild(el);
		save();
	}

	public static void main(String[] args) {
		DOMTest dom = new DOMTest();
		dom.show();
		dom.amend();
		dom.delete();
		dom.add();
	}

}