Java RMI Chat System

Can anyone please help me with the coding of this?
The system should allow each client user to chat anonymously with another client through the server. The server will act as a proxy server for the clients of the system. The Client will not be required to know the IP address or port number for the user they wish to chat with. The system shoul:
1. Register with the server by providing a unique user name (e.g. Mary2004). Un register with the server.
2. Query the server and receive a list of all currently registered users.
3. Send a message to a user based only on the username. The user will also obtain a unique number for each message sent to the server. The current date and time are also appended to each message( e.g. "12.12.05 15:45 - Hello Mary!").
4. Receive notification from the server if hte message has been rejected (e.g. "Message number 1234 has been rejected")
5. Reject or accept a mesage from another user.
Does anyone have code for this as I am struggling?
Monica

hahaha.....i dont think here the people will give u the code.....hehe....everything must try first before ask......get ur homework done.....see ya

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JSP client in RMI system - java.rmi.UnmarshalException: error unmarshalling

Hi,
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Here are my codes:
//Interface - Airline.java
package Air;
import java.rmi.*;
public interface Airline extends Remote
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}//implementation - AirlineImpl.java
import java.net.*;
import java.io.*;
import java.sql.*;
import java.rmi.*;
import java.rmi.server.UnicastRemoteObject;
public class AirlineImpl extends UnicastRemoteObject implements Airline
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import java.rmi.server.UnicastRemoteObject;
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<html>
<head>
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<%
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try
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catch (Exception e1)
%>
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<%
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hi all
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I am new to RMI concept
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hurry!
Thank u First of all
I got it.. finally after 2 days
The error is in CLASSPATH only , i set it
Thanks once again

Java.rmi.ServerException: RuntimeException

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code comes here-----------------------------------------------
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The other side has closed the socket before sending you an object.

Java.rmi.ServerException: Missing port information

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run-test-client:
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[java] at com.sun.xml.rpc.client.StreamingSender._send(StreamingSender.
java:234)
[java] at sys.SetIF_Stub.getdeviceid(SetIF_Stub.java:68)
[java] at sys.StockPriceFetcher.getdeviceid(Unknown Source)
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what cause it??
in my SetImpl.java i use wurfltags.jar
//SetImpl.java
package sys;
import java.io.*;
import java.net.*;
import java.util.*;
import net.sourceforge.wurfl.wurflapi.*;
public class SetImpl implements SetIF {
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private ProConf pc;
private MyObjectsManager mom;
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public String getdeviceid(String request)
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String result="";
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ex.printStackTrace();
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when i run the testpricefetcher.java it will raise the above error infomation.
it spent 2 days for me to find the problem, but i cannot solve it.
i think it does matter with the wurfl package.because i doesnt use the method of the package in the SetImpl.java it will be ok. How to call the package?please give me a hand.

can you give me a hand!thank you

Java.rmi.ServerException: JAXRPCSERVLET28: Missing port information

Hi
We are getting errors when we run the webservice client..
With this we have also provided the webservice code.
Please any one help us to resolve this issue...
Thanks in advance.
We are using
J2EE 1.4
Error:
java.rmi.ServerException: JAXRPCSERVLET28: Missing port information
at com.sun.xml.rpc.client.StreamingSender._raiseFault(StreamingSender.ja
va:510)
at com.sun.xml.rpc.client.StreamingSender._send(StreamingSender.java:307
at com.sun.xml.rpc.client.dii.CallInvokerImpl.doInvoke(CallInvokerImpl.j
ava:103)
at com.sun.xml.rpc.client.dii.BasicCall.invoke(BasicCall.java:492)
at com.sun.xml.rpc.client.dii.CallInvocationHandler.doCall(CallInvocatio
nHandler.java:121)
at com.sun.xml.rpc.client.dii.CallInvocationHandler.invoke(CallInvocatio
nHandler.java:85)
at $Proxy0.flowrequest(Unknown Source)
at dynamicproxy.MathClient.main(MathClient.java:52)
Web service Client Code:
package dynamicproxy;
import java.net.URL;
import javax.xml.rpc.Service;
import javax.xml.rpc.JAXRPCException;
import javax.xml.namespace.QName;
import javax.xml.rpc.ServiceFactory;
//import com.ibm.ctg.client.JavaGateway;
//import com.ibm.ctg.client.ECIRequest;
import dynamicproxy.*;
public class MathClient
static String message;
static String err=null;
     static StringBuffer sb = null;
     public String s1;
     public static int iValidationFailed = 0;
public static void main(String[] args)
try {
String nameSpaceUri = "urn:Foo";
String serviceName = "CtgService";
String portName = "MathFacePort";
// Specify the location of the WSDL file
URL url = new URL("http://localhost:8080/math-ctgservice/math?WSDL");
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ServiceFactory serviceFactory = ServiceFactory.newInstance();
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Service mathService = serviceFactory.createService(url,
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dynamicproxy.MathFace
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portName), dynamicproxy.MathFace.class);
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ex.printStackTrace();
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As is so often the case, Google is your friend.
Googling for the exception message (JAXRPCSERVLET28: Missing port information) yields the following list.
http://www.google.com/search?hl=en&q=JAXRPCSERVLET28%3A+Missing+port+information&btnG=Google+Search
Follow the bouncing link, it will lead you to the solution.
PS.

Java.rmi.ServerException: RemoteException occurred in server thread

I have written a simple CMP Entity Bean,While Running the Client I am getting the Exception,I have included all jars needed.
EXCEPTION IS
err in HomeCreatejava.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.ServerException: Could not instantiate bean; nested exception is:
java.lang.InstantiationException; nested exception is:
java.rmi.ServerException: Could not instantiate bean; nested exception is:
java.lang.InstantiationException
java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.ServerException: Could not instantiate bean; nested exception is:
java.lang.InstantiationException; nested exception is:
java.rmi.ServerException: Could not instantiate bean; nested exception is:
java.lang.InstantiationException
at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:287)
at sun.rmi.transport.Transport$1.run(Transport.java:151)
at java.security.AccessController.doPrivileged(Native Method)
at sun.rmi.transport.Transport.serviceCall(Transport.java:147)
at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:463)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:704)
at java.lang.Thread.run(Thread.java:539)
at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(StreamRemoteCall.java:250)
at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:226)
at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:136)
at org.jboss.invocation.jrmp.server.JRMPInvoker_Stub.invoke(Unknown Source)
at org.jboss.invocation.jrmp.interfaces.JRMPInvokerProxy.invoke(JRMPInvokerProxy.java:128)
at org.jboss.invocation.InvokerInterceptor.invoke(InvokerInterceptor.java:108)
at org.jboss.proxy.TransactionInterceptor.invoke(TransactionInterceptor.java:73)
at org.jboss.proxy.SecurityInterceptor.invoke(SecurityInterceptor.java:76)
at org.jboss.proxy.ejb.HomeInterceptor.invoke(HomeInterceptor.java:185)
at org.jboss.proxy.ClientContainer.invoke(ClientContainer.java:76)
at $Proxy0.create(Unknown Source)
at StudentClient.main(StudentClient.java:39)
Caused by: java.rmi.ServerException: Could not instantiate bean; nested exception is:
java.lang.InstantiationException; nested exception is:
java.rmi.ServerException: Could not instantiate bean; nested exception is:
java.lang.InstantiationException
at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:140)
at org.jboss.ejb.plugins.TxInterceptorCMT.runWithTransactions(TxInterceptorCMT.java:167)
at org.jboss.ejb.plugins.TxInterceptorCMT.invokeHome(TxInterceptorCMT.java:52)
at org.jboss.ejb.plugins.SecurityInterceptor.invokeHome(SecurityInterceptor.java:104)
at org.jboss.ejb.plugins.LogInterceptor.invokeHome(LogInterceptor.java:109)
at org.jboss.ejb.EntityContainer.invokeHome(EntityContainer.java:487)
at org.jboss.ejb.Container.invoke(Container.java:726)
at org.jboss.ejb.EntityContainer.invoke(EntityContainer.java:1055)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:491)
at org.jboss.invocation.jrmp.server.JRMPInvoker.invoke(JRMPInvoker.java:362)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:42)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:28)
at java.lang.reflect.Method.invoke(Method.java:313)
at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:256)
at sun.rmi.transport.Transport$1.run(Transport.java:151)
at java.security.AccessController.doPrivileged(Native Method)
at sun.rmi.transport.Transport.serviceCall(Transport.java:147)
at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:463)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:704)
at java.lang.Thread.run(Thread.java:539)
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java.lang.InstantiationException
at org.jboss.ejb.plugins.AbstractInstancePool.get(AbstractInstancePool.java:211)
at org.jboss.ejb.plugins.EntityInstanceInterceptor.invokeHome(EntityInstanceInterceptor.java:122)
at org.jboss.ejb.plugins.EntityLockInterceptor.invokeHome(EntityLockInterceptor.java:79)
at org.jboss.ejb.plugins.EntityCreationInterceptor.invokeHome(EntityCreationInterceptor.java:44)
at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:98)
... 20 more
Caused by: java.lang.InstantiationException
at sun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:33)
at java.lang.reflect.Constructor.newInstance(Constructor.java:263)
at java.lang.Class.newInstance0(Class.java:301)
at java.lang.Class.newInstance(Class.java:254)
at org.jboss.ejb.plugins.BMPPersistenceManager.createBeanClassInstance(BMPPersistenceManager.java:145)
at org.jboss.resource.connectionmanager.CachedConnectionInterceptor.createBeanClassInstance(CachedConnectionInterceptor.java:251)
at org.jboss.ejb.EntityContainer.createBeanClassInstance(EntityContainer.java:294)
at org.jboss.ejb.plugins.AbstractInstancePool.get(AbstractInstancePool.java:208)
... 24 more
Pls explain what can i do now.
regards,
NaveenBabu.A
my client code is
import javax.ejb.*;
import javax.naming.*;
import java.rmi.*;
import javax.rmi.*;
import java.util.*;
import student.student1.*;
public class StudentClient
public static void main(String args[])
System.out.println("i am in start");
StudentHome home= null;
try{
System.setProperty("java.naming.factory.initial", "org.jnp.interfaces.NamingContextFactory");
System.setProperty("java.naming.provider.url", "localhost:1099");
Context context = new InitialContext();
try{
home = (StudentHome)PortableRemoteObject.narrow(context.lookup("Student"), StudentHome.class);
}catch(Exception e){System.out.println("err in StudentHome"+e);}
/* try{
home.create("Ammamn","A01");
}catch(Exception e){System.out.println("err in HomeCreate"+e);}*/
}catch(Exception e){System.out.println("error in client"+e);}
System.out.println("i am in end");
}

Try this,
Context context = new InitialContext(System.getProperties());

WS - "java.rmi.MarshalException: (1)Missing end tag for Body or Envelope"

HI All,
I'm new of this forum but I really hope you could help me solving the problem I have to connect Web Services and midlets.
Somehow my configuration works with some services I've found online but when I invoke very simple services deployed on my server(s) I always have "java.rmi.MarshalException: (1)Missing end tag for Body or Envelope" exception"
Let me add some more information to the problem:
System Configuration:
- JBoss (but I also tried axis) - standard installation (http/1.1)
- WTK 2.5 (but I also tried 2.2) - standard installation
- I tried "trusted" and "untrusted" security configuration of the servlet
- Netbeans IDE 5.0 (to create both Midlets and WS)
- WS uses document/literal as expected by JSR 172
The midlet is created with no problems but at the time of invocation the server throws the above exception (which is part of rmi. remoteException)
By monitoring the network both at client and server side I noticed that the information received is chuncked after 768 bytes. However, If the (soap) reponse is less than such value, I still have the error.
Using Http/1.1. at the mobile side, the service does not return me anything (0kb) while if I set the mobile device to http/1.0, I get the above error.
I really have to make the midlet running so any type of help will be really appreciated!!
Thanks in advance

Hi all,
as many developers I have encountered the famous "java.rmi.MarshallException:(1)Missing end tag for Body or Envelope" during the development of my WS app for J2ME (JSR 172).
It is correct that is the empty tag <soapenv:Header /> causing this error.
To fix this error, it is necessary to stop the server to generate this empty header in the response stream.
I have fixed this error for Axis2: unfortunaly it is necessary to modify a class in Axiom library. This library is used in Axis2 to produce the SOAP response, you can download the source code at http://ws.apache.org/commons/axiom/source-repository.html.
Here the class to modify:
axiom\modules\axiom-impl\src\main\java\org\apache\axiom\soap\impl\llom\soap11\SOAP11Factory.java
by commenting the line 273 in the method called getDefaultEnvelope() to prevent the empty header insertion in SOAP response:
public SOAPEnvelope getDefaultEnvelope() throws SOAPProcessingException {
        OMNamespace ns =
                new OMNamespaceImpl(
                        SOAP11Constants.SOAP_ENVELOPE_NAMESPACE_URI,
                        SOAP11Constants.SOAP_DEFAULT_NAMESPACE_PREFIX);
        SOAPEnvelopeImpl env = new SOAPEnvelopeImpl(ns, this);
        //createSOAPHeader(env); the line to be commented
        createSOAPBody(env);
        return env;
    }Finally you have to recompile Axiom using Maven to obtain the fixed package axiom-impl.jar and to replace this package on the lib repository of your Axis2 server.
A little tricky to fix this bug but now my app runs perfectly ;)
Enjoy!
Romain Pellerin
http://www.gasp-mobilegaming.org

New to Java RMI

I am having problems with the following code that I am currently trying to understand RMI from Java head First, the following are meant to be part of an universal browser that the browser downloads and displays interactive Java GUIs. Can someone explain what I am doing wrong as I am still new to Java please?
import java.awt.*;
import javax.swing.*;
import java.rmi.*;
import java.awt.event.*;
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      frame.setSize(500,500);
      frame.setVisible(true);
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          mainPanel.add(svc.getGuiPanel());
          mainPanel.validate();
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      Object[] services = null;
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     server = (ServiceServer) obj;
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     return services;
   class MyListListener implements ActionListener {
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          Object selection = serviceList.getSelectedItem();
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public static void main(String[] args) {
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}I am able to compile the code but come up with the following error messages at runtime
java.rmi.ConnectException: Connection refused to host: 127.0.0.1; nested exception is:
     java.net.ConnectException: Connection refused
     at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:601)
     at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:198)
     at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:184)
     at sun.rmi.server.UnicastRef.newCall(UnicastRef.java:322)
     at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
     at java.rmi.Naming.lookup(Naming.java:84)
     at ServiceBrowser.getServicesList(ServiceBrowser.java:53)
     at ServiceBrowser.buildGUI(ServiceBrowser.java:19)
     at ServiceBrowser.main(ServiceBrowser.java:82)
Caused by: java.net.ConnectException: Connection refused
     at java.net.PlainSocketImpl.socketConnect(Native Method)
     at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
     at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
     at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:432)
     at java.net.Socket.connect(Socket.java:529)
     at java.net.Socket.connect(Socket.java:478)
     at java.net.Socket.<init>(Socket.java:375)
     at java.net.Socket.<init>(Socket.java:189)
     at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:22)
     at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:128)
     at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:595)
     ... 8 more
java.lang.NullPointerException
     at ServiceBrowser.getServicesList(ServiceBrowser.java:64)
     at ServiceBrowser.buildGUI(ServiceBrowser.java:19)
     at ServiceBrowser.main(ServiceBrowser.java:82)
Exception in thread "main" java.lang.NullPointerException
     at javax.swing.DefaultComboBoxModel.<init>(DefaultComboBoxModel.java:53)
     at javax.swing.JComboBox.<init>(JComboBox.java:175)
     at ServiceBrowser.buildGUI(ServiceBrowser.java:21)
     at ServiceBrowser.main(ServiceBrowser.java:82)
The code for the remote implementation compile and runs, but the other code for services compiles but come back with the following error message at runtime:
Exception in thread "main" java.lang.NoSuchMethodError: main
I have included one of the services code below this happens with:
import javax.swing.*;
import java.awt.event.*;
import java.io.*;
public class DiceService implements Service {
    JLabel label;
    JComboBox numOfDice;
    public JPanel getGuiPanel() {
       JPanel panel = new JPanel();
       JButton button = new JButton("Roll 'em!");
       String[] choices = {"1", "2", "3", "4", "5"};
       numOfDice = new JComboBox(choices);
       label = new JLabel("dice values here");
       button.addActionListener(new RollEmListener());
       panel.add(numOfDice);
       panel.add(button);
       panel.add(label);
       return panel;
   public class RollEmListener implements ActionListener {
      public void actionPerformed(ActionEvent ev) {
         // roll the dice
         String diceOutput = "";
         String selection = (String) numOfDice.getSelectedItem();
         int numOfDiceToRoll = Integer.parseInt(selection);
         for (int i = 0; i < numOfDiceToRoll; i++) {
            int r = (int) ((Math.random() * 6) + 1);
            diceOutput += (" " + r);
        label.setText(diceOutput);
}

how I do get suitable server running, can I not test the code on a local ip address first, i have included the remote implementation code below, can you advise how I can resolve this please or point me in the right direction?
import java.rmi.*;
import java.util.*;
import java.rmi.server.*;
public class ServiceServerImpl extends UnicastRemoteObject implements ServiceServer {
    HashMap<String, Service> serviceList;
    public ServiceServerImpl() throws RemoteException {
       // start and set up services
       setUpServices();
   private void setUpServices() {
       serviceList = new HashMap<String, Service>();
       serviceList.put("Dice Rolling Service", new DiceService());
       serviceList.put("Day of the Week Service", new DayOfTheWeekService());
       serviceList.put("Visual Music Service", new MiniMusicService());
    public Object[] getServiceList() {
       System.out.println("in remote");
       return serviceList.keySet().toArray();
    public Service getService(Object serviceKey) throws RemoteException {
       Service theService = (Service) serviceList.get(serviceKey);
       return theService;
    public static void main (String[] args) {
       try {
         Naming.rebind("ServiceServer", new ServiceServerImpl());
        } catch(Exception ex) { }
        System.out.println("Remote service is running");
}

Java.rmi.ConnectException: Connection refuse

Hi all,
I have built a simple RMI client server application.I can run client & server fine locally.
However if I test this appplication over the internet, I get this exception on the client:
java.rmi.ConnectException: Connection refused to host: 169.254.157.53; nested exception is:
java.net.ConnectException: Connection timed out: connectConnection refused to host:169.254.157.53
The RMI server is running on my PC and the client on a friend's remote PC.Both PCs are connected to Internet.
I don't have any firewall running on my PC (including windows XP firewall). The server RMI lookup on the client happens correctly,
the exception is raised when the client tries to call the remote method on the server.
Here is an extract of my RMI server code (it works locally):
public static void main(String[] args) throws Exception {
          try {
          // args[0] contains the database server name given as command line argument, arg[1] contains binary path that contains weather jpeg files
          CPrimaryWeatherServer test = new CPrimaryWeatherServer(args[0], args[1]);
          Naming.rebind("rmi://localhost:1099/WeatherPrimaryService", test);
          System.out.println("Serveur m�t�o principal d�marr�");
          } catch (Exception e){ System.out.println(e.getMessage());}
Here is an extract of my RMI client code (it works locally):
try{
                    rec=1;
                    leftClik=1;
                    System.out.println("Before RMI lookup");
                    IPrimaryWeatherServerService serveur =(IPrimaryWeatherServerService)Naming.lookup("rmi://"+primWS+":1099/WeatherPrimaryService");
                    System.out.println("After RMI lookup");
                    System.out.println("Before server method call");
                    z=serveur.getFullWeatherData(); --> exception is raised here
                    System.out.println("After RMI server method call");
I am directly connected to Internet using an ethernet card connected to an ADSL modem.169.254.157.53 is the automatic IP of my network card different from the IP given by my ISP. By the way, the client tries to contact me using my DNS name that resolves correctly to my ISP IP adress.
Thanks a lot for help,

because I am guessing that a local IP address is being embedded into the stub so the clien't can't find the remote server. I am guessing because you didn't provide the exception or its text. Anyway the suggestion will cause the correct public IP address/hostname to be embedded into the stub.

Java.rmi.MarshalException is thrown when we run JUnit TestCase

Hi,
We wrote a JUnit TestCase to test our EJBs of our J2EE project.
When we run the JUnit TestCase, we are facing Marshalling Exception.
Our application development IDE is WSAD5.0 and it's JUnit jar's version is 3.8.1
But the application is running fine when we manually run the application. This makes clear that there is no problem in the application.
And also all the required classes are implementing Serializable.
Here is the actual stack trace of the exception:
java.rmi.MarshalException: CORBA MARSHAL 0x0 No; nested exception is:
     org.omg.CORBA.MARSHAL: minor code: 0 completed: No
org.omg.CORBA.MARSHAL: minor code: 0 completed: No
     at java.lang.Class.newInstance0(Native Method)
     at java.lang.Class.newInstance(Class.java:262)
     at com.ibm.rmi.iiop.ReplyMessage.getSystemException(ReplyMessage.java:206)
     at com.ibm.rmi.iiop.ClientResponseImpl.getSystemException(ClientResponseImpl.java:130)
     at com.ibm.CORBA.iiop.ClientDelegate.invoke(ClientDelegate.java:556)
     at com.ibm.CORBA.iiop.ClientDelegate.invoke(ClientDelegate.java:708)
     at org.omg.CORBA.portable.ObjectImpl._invoke(ObjectImpl.java:258)
     at fos.server.lt.medicalInsurance.sbMedicalInsurance._MedicalInsuranceRemote_Stub.getInterventionFee(_MedicalInsuranceRemote_Stub.java:395)
     at getIntFeeEJB.CTestCase_Default._Default_0(CTestCase_Default.java:393)
     at getIntFeeEJB.CTestCase_Default.test_Default_0(CTestCase_Default.java:413)
     at java.lang.reflect.Method.invoke(Native Method)
     at junit.framework.TestCase.runTest(TestCase.java:154)
     at junit.framework.TestCase.runBare(TestCase.java:127)
     at junit.framework.TestResult$1.protect(TestResult.java:106)
     at junit.framework.TestResult.runProtected(TestResult.java:124)
     at junit.framework.TestResult.run(TestResult.java:109)
     at junit.framework.TestCase.run(TestCase.java:118)
     at junit.framework.TestSuite.runTest(TestSuite.java:208)
     at junit.framework.TestSuite.run(TestSuite.java:203)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:329)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:218)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:151)
Any idea how to resolve this issue. if so, please help.

i changed my plan to test application ng the way
mentioned above. But i think that it was due to lack
of memory on the system.
I hope this will be helpful.I got probleem whit java applet whit error report 3701
I hope jou can help me

Chat System: ConnectException: Connection timed out: connect

Hi There,
I am developing a chat system as part of a University project.
To explain what I have implemented:
I have three java classes;
1. Chat Server class which is constantly listening for incoming socket connection on a particular socket:
while (true)
Socket client = server.accept ();
System.out.println ("Accepted from " + client.getInetAddress ());
ChatHandler c = new ChatHandler (client);
c.start ();
2. Chat Handler class uses a thread for each client to handle multiple clients:
public ChatHandler (Socket s) throws IOException
this.s = s;
i = new DataInputStream (new BufferedInputStream (s.getInputStream ()));
o = new DataOutputStream (new BufferedOutputStream (s.getOutputStream ()));
public void run ()
try
handlers.addElement (this);
while (true)
String msg = i.readUTF ();
broadcast (msg);
catch (IOException ex)
ex.printStackTrace ();
finally
handlers.removeElement (this);
try
s.close ();
catch (IOException ex)
ex.printStackTrace();
protected static void broadcast (String message)
synchronized (handlers)
Enumeration e = handlers.elements ();
while (e.hasMoreElements ())
ChatHandler c = (ChatHandler) e.nextElement ();
try
synchronized (c.o)
c.o.writeUTF (message);
c.o.flush ();
catch (IOException ex)
c.stop ();
3. Chat Client class which has a simple GUI and sends messages to the server to be broadcasted to all other clients on the same socket port:
public ChatClient (String title, InputStream i, OutputStream o)
super (title);
this.i = new DataInputStream (new BufferedInputStream (i));
this.o = new DataOutputStream (new BufferedOutputStream (o));
setLayout (new BorderLayout ());
add ("Center", output = new TextArea ());
output.setEditable (false);
add ("South", input = new TextField ());
pack ();
show ();
input.requestFocus ();
listener = new Thread (this);
listener.start ();
public void run ()
try
while (true)
String line = i.readUTF ();
output.appendText (line + "\n");
catch (IOException ex)
ex.printStackTrace ();
finally
listener = null;
input.hide ();
validate ();
try
o.close ();
catch (IOException ex)
ex.printStackTrace ();
public boolean handleEvent (Event e)
if ((e.target == input) && (e.id == Event.ACTION_EVENT)) {
try {
o.writeUTF ((String) e.arg);
o.flush ();
} catch (IOException ex) {
ex.printStackTrace();
listener.stop ();
input.setText ("");
return true;
} else if ((e.target == this) && (e.id == Event.WINDOW_DESTROY)) {
if (listener != null)
listener.stop ();
hide ();
return true;
return super.handleEvent (e);
public static void main (String args[]) throws IOException
Socket s = new Socket ("192.168.2.3",4449);
new ChatClient ("Chat test", s.getInputStream (), s.getOutputStream ());
On testing this simple app on my local host I have launched several instances of ChatClient and they interact perfectly between each other.
Although when i test this app by launching ChatClient on another machine (using a wi-fi network connection at home), on the other machine that tries to connect to the hosting server (my machine) i get a "connection timed out" on the chatClient machine.
I have added the port and ip addresses in concern to the exceptions to by-pass the firewall but i am still getting the timeout.
Any suggestions?
Thanks!

Format your code with [ code ] tag pair.
If you are a young university student I don't understand why current your code uses so many of
too-too-too old APIs including deprecated ones.
For example, DataInput/OutputStream should never be used for text I/Os because they aren't
always reliable.
Use Writers and Readers in modern Java programming
Here's a simple and standard chat program example:
(A few of obsolete APIs from your code remain here, but they are no problem.
Tested both on localhost and a LAN.)
/* ChatServer.java */
import java.io.*;
import java.util.*;
import java.net.*;
public class ChatServer{
ServerSocket server;
public ChatServer(){
    try{
      server = new ServerSocket(4449);
      while (true){
        Socket client = server.accept();
        System.out.println("Accepted from " + client.getInetAddress());
        ChatHandler c = new ChatHandler(client);
        c.start ();
    catch (IOException e){
      e.printStackTrace();
public static void main(String[] args){
    new ChatServer();
class ChatHandler extends Thread{
static Vector<ChatHandler> handlers = new Vector<ChatHandler>();
Socket s;
BufferedReader i;
PrintWriter o;
public ChatHandler(Socket s) throws IOException{
    this.s = s;
    i = new BufferedReader(new InputStreamReader(s.getInputStream()));
    o = new PrintWriter
     (new BufferedWriter(new OutputStreamWriter(s.getOutputStream())));
public void run(){
    try{
      handlers.addElement(this);
      while (true){
        String msg = i.readLine();
        broadcast(msg);
    catch (IOException ex){
      ex.printStackTrace();
    finally{
      handlers.removeElement(this);
      try{
        s.close();
      catch (IOException e){
        e.printStackTrace();
protected static void broadcast(String message){
    synchronized (handlers){
      Enumeration e = handlers.elements();
      while (e.hasMoreElements()){
        ChatHandler c = (ChatHandler)(e.nextElement());
        synchronized (c.o){
          c.o.println(message);
          c.o.flush();
/* ChatClient.java */
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.io.*;
public class ChatClient extends JFrame implements Runnable{
Socket socket;
JTextArea output;
JTextField input;
BufferedReader i;
PrintWriter o;
Thread listener;
JButton endButton;
public ChatClient (String title, Socket s){
    super(title);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    socket = s;
    try{
      i = new BufferedReader(new InputStreamReader(s.getInputStream()));
      o = new PrintWriter
       (new BufferedWriter(new OutputStreamWriter(s.getOutputStream())));
    catch (IOException ie){
      ie.printStackTrace();
    Container con = getContentPane();
    con.add (output = new JTextArea(), BorderLayout.CENTER);
    output.setEditable(false);
    con.add(input = new JTextField(), BorderLayout.SOUTH);
    con.add(endButton = new JButton("END"), BorderLayout.NORTH);
    input.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent ae){
        o.println(input.getText());
        o.flush();
        input.setText("");
    endButton.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent ev){
        try{
          socket.close();
        catch (IOException ie){
          ie.printStackTrace();
        System.exit(0);
    setBounds(50, 50, 500, 500);
    setVisible(true);
    input.requestFocusInWindow();
    listener = new Thread(this);
    listener.start();
public void run(){
    try{
      while (true){
        String line = i.readLine();
        output.append(line + "\n");
    catch (IOException ex){
      ex.printStackTrace();
    finally{
      o.close();
public static void main (String args[]) throws IOException{
    Socket sock = null;
    String addr = "127.0.0.1";
    if (args.length > 0){
      addr = args[0];
    sock = new Socket(addr, 4449);
    new ChatClient("Chat Client", sock);
}

UnmarshalException while using prop java.rmi.server.ignoreStubClasses=true

I have created a test program to check the behaviour of setting the java.rmi.server.ignoreStubClasses property to true on the server side and not setting this flag on the client side.
This requirement is due to updation of an already running system, with stubs to a new version without stubs, without shutting down the system.
The files used by me are given below.
File Hello.java
package example.hello;
import java.rmi.Remote;
import java.rmi.RemoteException;
public interface Hello extends Remote {
String sayHello() throws RemoteException;
File Server.java
package example.hello;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
import java.rmi.server.UnicastRemoteObject;
public class Server implements Hello {
public Server() {}
public String sayHello() {
return "Hello, world!";
public static void main(String args[]) {
try {
LocateRegistry.createRegistry(1099);
Server obj = new Server();
Hello stub = (Hello) UnicastRemoteObject.exportObject(obj, 0);
// Bind the remote object's stub in the registry
Registry registry = LocateRegistry.getRegistry();
registry.bind("Hello", stub);
System.err.println("Server ready");
catch (Exception e)
System.err.println("Server exception: " + e.toString());
e.printStackTrace();
File Client.java
package example.hello;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
public class Client {
private Client() {}
public static void main(String[] args) {
String host = (args.length < 1) ? null : args[0];
try {
Registry registry = LocateRegistry.getRegistry(host);
Hello stub = (Hello) registry.lookup("Hello");
String response = stub.sayHello();
System.out.println("response: " + response);
} catch (Exception e) {
System.err.println("Client exception: " + e.toString());
e.printStackTrace();
First I run file Server.java using the following script (server.bat)
java -Djava.rmi.server.ignoreStubClasses=true -classpath .; example.hello.Server
pause
Then the client is run using the following script (client.bat)
java -classpath .; example.hello.Client 132.186.96.210
pause
While running the client, the following exception is obtained.
Client exception: java.rmi.ServerException: RemoteException occurred in server thread; nested except
java.rmi.UnmarshalException: error unmarshalling call header; nested exception is:
java.rmi.UnmarshalException: skeleton class not found but required for client version
java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.UnmarshalException: error unmarshalling call header; nested exception is:
java.rmi.UnmarshalException: skeleton class not found but required for client version
at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:325)
at sun.rmi.transport.Transport$1.run(Transport.java:153)
at java.security.AccessController.doPrivileged(Native Method)
at sun.rmi.transport.Transport.serviceCall(Transport.java:149)
at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
at java.lang.Thread.run(Thread.java:595)
at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(StreamRemoteCall.java:247)
at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:223)
at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:343)
at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
at example.hello.Client.main(Client.java:52)
Caused by: java.rmi.UnmarshalException: error unmarshalling call header; nested exception is:
java.rmi.UnmarshalException: skeleton class not found but required for client version
at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:250)
at sun.rmi.transport.Transport$1.run(Transport.java:153)
at java.security.AccessController.doPrivileged(Native Method)
at sun.rmi.transport.Transport.serviceCall(Transport.java:149)
at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
at java.lang.Thread.run(Thread.java:595)
Caused by: java.rmi.UnmarshalException: skeleton class not found but required for client version
at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:243)
... 6 more
I am not able to figure out why this thing is happening, If i also set the property java.rmi.server.ignoreStubClasses=true on the client side everything goes fine. But this I can't do. I can't set the property on the client side as the system is up and already running.
I am using JDK version 1.5.0_06. Same exception comes under JDK 6.0
Any help will be highly appreciated.

I think this is a bug. When you exported the Registry from your server JVM it was also exported with java.rmi.server.ignoreStubClasses=true, but the Registry bootstrap at the client requires the 1.1 stub protocol for compatiblity reasons so you got this error. I would report this on the Bug Parade.
You could get around it by setting java.rmi.server.ignoreStubClasses after exporting the Registry.
BTW java.rmi.server.ignoreStubClasses isn't supposed to do anything at the client whether true or false so you can cut your testing space in half.

Java RMI Chat System

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