com.caucho.hessian.io.HessianProtocolException : unexpected object java.lang.String

FxClient.fx [Client]

import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.text.Text;
import javafx.scene.text.Font;
import javafx.scene.layout.HBox;
import javafx.scene.paint.Color;
import javafx.scene.text.TextOrigin;
import javafx.ext.swing.SwingButton;
import javafx.scene.layout.VBox;
import javafx.scene.control.TextBox;
import HelloworldClient;

class Hello {
public var name:String;
public var str:String;
}

var helloModel = new Hello();
HelloworldClient.setServerUrl("http://localhost:8080/flamingoseamserver/flamingo/hessian/helloAction");
var helloText: TextBox = TextBox {
text: bind helloModel.name with inverse
columns: 7
selectOnFocus:true
}
var helloLabel = Text{
y:8
font: Font { name:"sansserif", size: 12 }
fill: Color.BLACK
content: bind "Server says: {helloModel.str}"
textOrigin: TextOrigin.TOP
}
var helloButton = SwingButton {
text:"Say Hello!"
action: function(){
helloModel.str =
HelloworldClient.CLIENT.hello(helloModel.name);
}
}
Stage {
title: "Helloworld Sample"
width: 200
height: 150
scene: Scene {
content: VBox {
translateX: 5
translateY: 5
spacing: 10
content: [
HBox {
content: helloText
spacing: 10
},
HBox {
content: helloButton
spacing: 10
},
HBox {
content: helloLabel
spacing: 10
}]
}
}
}

End FxClient.fx [Client]

HelloWorldClient.java [Client]

import com.caucho.hessian.client.HessianProxyFactory;
import java.net.MalformedURLException;

public class HelloworldClient {
public static HelloworldClient CLIENT;
private String _url;

private HelloworldClient(String string) {
_url = string;
}

private IHelloAction _service;

public static void setServerUrl(String url) {
CLIENT = new HelloworldClient(url);
}

private IHelloAction getService() {
if (_service == null) {
try {
HessianProxyFactory factory = new HessianProxyFactory();
_service = (IHelloAction) factory.create(IHelloAction.class,
_url);
} catch (MalformedURLException ex) {
System.out.println(ex);
}
}
return _service;
}

public String hello(String s) {
return getService().hello(s);
}
}

End HelloWorldClient.java [Client]

IHelloAction.java [Client]

public interface IHelloAction {
public String hello(String name);
}

End IHelloAction.java [Client]

HelloAction.java [Server]

import org.jboss.seam.ScopeType;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.annotations.Scope;

@Scope(ScopeType.STATELESS)
@Name("helloAction")
public class HelloAction implements IHelloAction {

public String hello(String name) {
return "Hello, " + name;
}
}

End HelloAction.java [Server]

IHelloAction.java [Server]

import org.jboss.seam.annotations.remoting.WebRemote;

public interface IHelloAction {

@WebRemote
public String hello(String name);
}

End IHelloAction.java [Server]