Webservice XFireの問題

XFireでwebserviceを開発する際、問題が発生し、オブジェクトを取得する必要がある場合、次のエラーが発生します.

Exception in thread "main" org.codehaus.xfire.XFireRuntimeException: Could not invoke service.. Nested exception is org.codehaus.xfire.fault.XFireFault: Couldn't instantiate class. com.xfire.pojo.Student
org.codehaus.xfire.fault.XFireFault: Couldn't instantiate class. com.xfire.pojo.Student
	at org.codehaus.xfire.aegis.type.basic.BeanType.readObject(BeanType.java:196)
	at org.codehaus.xfire.aegis.AegisBindingProvider.readParameter(AegisBindingProvider.java:169)
	at org.codehaus.xfire.service.binding.AbstractBinding.read(AbstractBinding.java:206)
	at org.codehaus.xfire.service.binding.WrappedBinding.readMessage(WrappedBinding.java:51)
	at org.codehaus.xfire.soap.handler.SoapBodyHandler.invoke(SoapBodyHandler.java:42)
	at org.codehaus.xfire.handler.HandlerPipeline.invoke(HandlerPipeline.java:131)
	at org.codehaus.xfire.client.Client.onReceive(Client.java:406)
	at org.codehaus.xfire.transport.http.HttpChannel.sendViaClient(HttpChannel.java:139)
	at org.codehaus.xfire.transport.http.HttpChannel.send(HttpChannel.java:48)
	at org.codehaus.xfire.handler.OutMessageSender.invoke(OutMessageSender.java:26)
	at org.codehaus.xfire.handler.HandlerPipeline.invoke(HandlerPipeline.java:131)
	at org.codehaus.xfire.client.Invocation.invoke(Invocation.java:79)
	at org.codehaus.xfire.client.Invocation.invoke(Invocation.java:114)
	at org.codehaus.xfire.client.Client.invoke(Client.java:336)
	at org.codehaus.xfire.client.XFireProxy.handleRequest(XFireProxy.java:77)
	at org.codehaus.xfire.client.XFireProxy.invoke(XFireProxy.java:57)
	at $Proxy0.getStudentByName(Unknown Source)
	at com.xfire.TestClient.main(TestClient.java:31)
Caused by: java.lang.InstantiationException: com.xfire.pojo.Student
	at java.lang.Class.newInstance0(Unknown Source)
	at java.lang.Class.newInstance(Unknown Source)
	at org.codehaus.xfire.aegis.type.basic.BeanType.readObject(BeanType.java:109)
	... 17 more

Student.java

package com.xfire.pojo;

public class Student {

	private String name;
	
	private int age;
	
	
	
	public Student(String name,int age)
	{
		this.name=name;
		this.age=age;
	}

	public int getAge() {
		return age;
	}

	public void setAge(int age) {
		this.age = age;
	}

	public String getName() {
		return name;
	}

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

インタフェースjava

package com.xfire;

import com.xfire.pojo.Student;

public interface ITestService {
	
	public String example(String message);
	
	public Student getStudentByName(String name);
	
	public int sum(int c1,int c2);
	
}

実装クラス:ITestServiceImpl.java

package com.xfire;

import com.xfire.pojo.Student;
//Generated by MyEclipse

public class TestServiceImpl implements ITestService {
	
	private StudentUtility utility;
	
	public TestServiceImpl()
	{
		utility=new StudentUtility();
	}
	
	public String example(String message) {
		return message;
	}

	public Student getStudentByName(String name) {
		return utility.getStudentByName(name);
	}

	public int sum(int c1, int c2) {
		return c1+c2;
	}
	
}

ビジネスクラス:StudentUtility.java

package com.xfire;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.xfire.pojo.Student;

public class StudentUtility {

	private Map<String, Student> studentmap;
	
	public StudentUtility()
	{
		studentmap=new HashMap<String, Student>();
		studentmap.put("Alvin", new Student("Alvinqq",25));
		studentmap.put("ZengQi", new Student("ZengQi",25));
		studentmap.put("Shirley", new Student("Shirley",23));
	}
	
	public Student getStudentByName(String name)
	{
		return studentmap.get(name);
	}
	
	public List<Student> getStudents()
	{
		List<Student> list=new ArrayList<Student>();
		Set<String> key=new HashSet<String>();
		key=studentmap.keySet();
		Iterator<String> iter=key.iterator();
		while(iter.hasNext())
		{
			list.add(studentmap.get(iter.next()));
		}
		return list;
	}
}

クライアント呼び出しクラス:TestClient.java

package com.xfire;

import java.net.MalformedURLException;

import org.codehaus.xfire.XFireFactory;
import org.codehaus.xfire.client.XFireProxyFactory;
import org.codehaus.xfire.service.Service;
import org.codehaus.xfire.service.binding.ObjectServiceFactory;

import com.xfire.pojo.Student;


public class TestClient {

	/**
	 * @param args
	 */
	public static void main(String[] args) {

		Service service=new ObjectServiceFactory().create(ITestService.class);
		
		XFireProxyFactory factory=new XFireProxyFactory(XFireFactory.newInstance().getXFire());
		
		String url="http://localhost/webServiceXFire/services/TestService";
		
		try {
			ITestService srv=(ITestService) factory.create(service,url);
			String result=srv.example("Hello");
			System.out.println(result);
			System.out.println(srv.sum(2, 6));
			System.out.println(srv.getStudentByName("Alvin").getAge());		} catch (MalformedURLException e) {
			e.printStackTrace();
		}
	}

}

長い間探していた理由はJAvaには無パラメトリック構造が1つ欠けています.加えてください.