apache common Digester 解析XML文件的问题

[yixiaogang109]

<student name="Tom" course="JSP"/>
和
<student>
<name>Tom</name>
<course>JSP</course>
</student>
这个有什么去吧吗？
我用apache common Digester 解析XML的时候，为什么用
<student>
<name>Tom</name>
<course>JSP</course>
</student>
有结果，而用
<student name="Tom" course="JSP"/>就没有结果啊？
我的代码下

package com.tongda.whl.digester;

import java.util.Vector;

import org.apache.commons.digester3.Digester;

public class DigestTest {

	@SuppressWarnings("unchecked")
	private Vector students;

	@SuppressWarnings("unchecked")
	public DigestTest() {
		students = new Vector(5);
	}

	public void addStudent(Student student) {
		students.add(student);
	}

	public String toString() {
		return ((Student) students.get(0)).getName();
	}

	public void digest() {
		// digest2.0支持jdk1.5,并且依赖 logging 1.1.1 和 beanutils 1.8.0
		// 创建实例
		Digester digester = new Digester();
		// 将初始对象压入digester的stack
		digester.push(this);
		// 指明匹配模式和要创建的类
		digester.addObjectCreate("students/student", Student.class);
		// 设置对象属性
		// digester
		digester.addBeanPropertySetter("students/student/name");
		digester.addBeanPropertySetter("students/student/course");
		// 当移动到下一个标签中时的动作
		digester.addSetNext("students/student", "addStudent");
		try {
			// 解析，xml文件放在classpath下
			DigestTest ds = (DigestTest) digester.parse(getClass()
					.getClassLoader().getResourceAsStream("students.xml"));
			System.out.println(ds);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	public static void main(String args[]) {
		DigestTest test = new DigestTest();
		test.digest();
	}

}

package com.tongda.whl.digester;

public class Student {

	private String name;
	private String course;

	public void setName(String name) {
		this.name = name;
	}

	public void setCourse(String course) {
		this.course = course;
	}

	public String getName() {
		return this.name;
	}

	public String getCourse() {
		return this.course;
	}
}

<students>
	<student name="Tom" course="JSP"/>
</students>