NAPT Firewall, RMI Callbacks and JRMP MultiplexProtocol

Hi All,
I am looking at having an RMI client behind a Network Address Port Translation firewall receive RMI calls back from an RMI server. NAPT makes it impossible for the client to listen for connection coming from the server through the NAPT firewall.
This is discussed at http://www.rmiproxy.com and http://cssassociates.com/rmifirewall.html but the proposed solutions do not appear to use the MultiplexProtocol protocol defined by JRMP (http://java.sun.com/j2se/1.4.2/docs/guide/rmi/spec/rmi-protocol3.html).
The RMI FAQ
"How can I receive incoming RMI calls through a local firewall"?
(http://java.sun.com/j2se/1.3/docs/guide/rmi/faq.html#firewallIn) had a section for JSSE 1.3 that explained how to use the multiplex protocol (option 4). It sounds like this option referred to the JRMP MultiplexProtocol protocol.
The multiplex protocol option has been removed from the 1.4 FAQ
(http://java.sun.com/j2se/1.4.2/docs/guide/rmi/faq.html#firewallIn).
Tried the "checkListen" and "socket factory" techniques mentioned in the 1.3 FAQ without success with 1.4.2. The RMI client behind the NAPT firewall runs in a signed Applet.
Is the ability of using the JRMP MultiplexProtocol protocol available in the JRE in order to receive incoming RMI calls through a local firewall? If yes, what do you do in order to use it?
What is the best way to have RMI callbacks work behind NAPT?
Thanks a lot in advance!
Cheers
Bertrand

As of about JDK 1.2.2, the ability of RMI clients to negotiate the multiplex protocol was
removed, but the server-side support remains.
Your best answer for negotiating NAT filrewalls may be the RMI Proxy http://www.rmiproxy.com, although I could be biased as I wrote it.
EJP

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"DEADLOCK" when showing dialog from RMI-callback.

Hi!
Today is the 10th day (full time) that I've been searching for a solution in Java Forums and Internet, but I couldn't find anything that helps me. Help is extremely appreciated, otherwise I'll go crazy! :-)
The problem is that RMI-callback thread "somehow blocks" the Event Dispatch Thread.
I want to do following:
1) I push the button in the client (btDoSomething)
(MOUSE_RELEASED,(39,14),button=1,modifiers=Button1,clickCount=1 is automatically pushed onto EventQueue)
2) btDoSomethingActionPerformed is invoked
3) inside of it I make a call to RMI-server (server.doSomething())
4) from this server method I invoke RMI-callback back to the client (client.askUser())
5) in the callback I want to display a question to the user (JOptionPane.showConfirmDialog)
6) user should answers the question
7) callback returns to server
8) client call to the server returns
9) btDoSomethingActionPerformed returns and everybody is happy :-)
This works normally in normal Client, that means, while a button is pushed, you can show Dialogs, but with RMI callback I get problems.
I just made a small client-server sample to simulate real project. What I want to achieve is that client invokes server method, server method does something, but if server method doesn't have enough information to make the decision it needs to do call back to the client and wait for input, so the user gets an JOptionPane.
Here is my callback method:
    /** this is the remote callback method, which is invoked from the sevrer */
    public synchronized String askUser() throws java.rmi.RemoteException {
        System.out.println("askUser() thread group: " + Thread.currentThread().getThreadGroup());
        System.out.println("callback started...");
        try {
            SwingUtilities.invokeLater(new Runnable() {
                public void run() {
                    System.out.println("My event started...");
                    JOptionPane.showConfirmDialog(parentFrame, "Are you OK?", "Question", JOptionPane.YES_NO_OPTION);
                    System.out.println("My event finished.");
        }catch (Exception e) {
            e.printStackTrace();
        try {
            Thread.currentThread().sleep(10000);
        }catch (Exception e) {
            e.printStackTrace();
        System.out.println("callback finished.");
        return "Yo!"; // just return anything
    }Here in this sample I let the callback thread sleep for 10 seconds, but in real project I let it sleep infinitely and I want to wake it up after the user has answered JOptionPane. But I have the DEADLOCK, because event queue is waiting for callback to finish and doesn't schedule the "showing dialog" event which contains the command for waking up the callback thread.
I looked very precisely when the event queue starts again to process events: it is precisely then when btDoSomethingActionPerformed is finished.
When I'm not accessing GUI inside of the callback, this callback mechanism works perfectly, but as soon as I want to show the dialog from inside of the RMI-callback method, the "AWT Event Dispatch Queue" is somehow frozen until RMI-callback thread is finished (and in turn btDoSomethingActionPerformed terminates) . I cannot explain this weird behaviour!!!
If I don't use SwingUtilities.invokeLater (I know this shoudn't be done outside of Event Dispatch Thread), but access the GUI directy, my JOptionPane is shown, but is not painted (it is blank gray) until callback thread returns.
Why showing (or painting) of dialog is not done until btDoSomethingActionPerformed is finished?
I also tried to spawn a new Thread inside of main RMI-callback thread, but nothing changed.
I also tried the workaround from some older posting to use myInvokeLater:
    private final static ThreadGroup _applicationThreadGroup = Thread.currentThread().getThreadGroup();
    public void myInvokeLater(final Runnable code) {
        (new Thread(_applicationThreadGroup, new Runnable() {
            public void run() { SwingUtilities.invokeLater(code); }
        ).start();
    }but this didn't help either.
Then I tried to spawn a new Thread directly from the Client's constructor, so that I'm sure that it belongs to the main appplication thread group. I even started that thread there in the constructor and made it wait for the callback. When callback came in, it would wake up that sleeping thread which should then show the dialog. But this did't help either.
Now I think that it is IMPOSSIBLE to solve this problem this way.
Spawning a new Process could work I think, but I'm not really sure if I want do to that.
I know I could make a solution where server method is invoked and if some information is missing I can raise custom exception, provide the input on client side and call the same server mathod again with this additional data, but for that I need to change server RMI interfaces, etc... to fit in this concept. I thought callback would much easier, but after almost 10 days of trying the callback...I almost regreted it :-(
Is anyone able to help?
Thank you very much!
Please scroll down for the complete sample (with build and run batch files), in case someone wants to try it. Or for the time being for your convenience you can download the whole sample from
http://www.onlineloop.com/~tornado/download/rmi_callback_blocks_gui.zip
######### BEGIN CODE ####################################
package callbackdialog;
public interface ICallback extends java.rmi.Remote {
    public String askUser() throws java.rmi.RemoteException;
package callbackdialog;
public interface IServer extends java.rmi.Remote {
    public void doSomething() throws java.rmi.RemoteException;
package callbackdialog;
import java.rmi.Naming;
public class Server {
    public Server() {
        try {
            IServer s = new ServerImpl();
            Naming.rebind("rmi://localhost:1099/ServerService", s);
        } catch (Exception e) {
            System.out.println("Trouble: " + e);
    public static void main(String args[]) {
        new Server();
package callbackdialog;
import java.rmi.Naming;
public class ServerImpl extends java.rmi.server.UnicastRemoteObject implements IServer {
    // Implementations must have an explicit constructor
    // in order to declare the RemoteException exception
    public ServerImpl() throws java.rmi.RemoteException {
        super();
    public void doSomething() throws java.rmi.RemoteException {
        System.out.println("doSomething started...");
        try {
            // ask the client for the "missing" value via RMI callback
            ICallback client = (ICallback)Naming.lookup("rmi://localhost/ICallback");
            String clientValue = client.askUser();
            System.out.println("Got value from callback: " + clientValue);
        }catch (Exception e) {
            e.printStackTrace();
        System.out.println("doSomething finished.");
package callbackdialog;
import java.rmi.server.RemoteStub;
import java.rmi.server.UnicastRemoteObject;
import java.rmi.registry.Registry;
import java.rmi.registry.LocateRegistry;
import java.rmi.Naming;
import javax.swing.JOptionPane;
import javax.swing.SwingUtilities;
import javax.swing.JFrame;
public class Client extends javax.swing.JFrame implements ICallback {
    private final JFrame parentFrame = this;
    private Registry mRegistry = null;
    private RemoteStub remoteStub = null;
    private IServer server = null;
    private final static ThreadGroup _applicationThreadGroup = Thread.currentThread().getThreadGroup();
    /** Creates new form Client */
    public Client() {
        initComponents();
        System.out.println("Client constructor thread group: " + Thread.currentThread().getThreadGroup());
        try {
            server = (IServer)Naming.lookup("rmi://localhost/ServerService");
            // register client to the registry, so the server can invoke callback on it
            mRegistry = LocateRegistry.getRegistry("localhost", 1099);
            remoteStub = (RemoteStub)UnicastRemoteObject.exportObject((ICallback)this);
            Registry mRegistry = LocateRegistry.getRegistry("localhost", 1099);
            mRegistry.bind("ICallback", remoteStub);
        }catch (java.rmi.AlreadyBoundException e) {
            try {
                mRegistry.unbind("ICallback");
                mRegistry.bind("ICallback", remoteStub);
            }catch (Exception ex) {
                // ignore it
        }catch (Exception e) {
            e.printStackTrace();
    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
    private void initComponents() {
        java.awt.GridBagConstraints gridBagConstraints;
        secondTestPanel = new javax.swing.JPanel();
        btDoSomething = new javax.swing.JButton();
        getContentPane().setLayout(new java.awt.GridBagLayout());
        setDefaultCloseOperation(javax.swing.WindowConstants.DISPOSE_ON_CLOSE);
        setTitle("RMI-Callback-GUI-problem sample");
        addWindowListener(new java.awt.event.WindowAdapter() {
            public void windowClosing(java.awt.event.WindowEvent evt) {
                formWindowClosing(evt);
        secondTestPanel.setLayout(new java.awt.GridBagLayout());
        btDoSomething.setText("show dialog");
        btDoSomething.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btDoSomethingActionPerformed(evt);
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 3;
        gridBagConstraints.insets = new java.awt.Insets(10, 0, 0, 0);
        secondTestPanel.add(btDoSomething, gridBagConstraints);
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.fill = java.awt.GridBagConstraints.BOTH;
        gridBagConstraints.weightx = 1.0;
        gridBagConstraints.weighty = 1.0;
        getContentPane().add(secondTestPanel, gridBagConstraints);
        pack();
    private void btDoSomethingActionPerformed(java.awt.event.ActionEvent evt) {
        System.out.println(java.awt.EventQueue.getCurrentEvent().paramString());
        try {
            server.doSomething(); // invoke server RMI method, which will do the client RMI-Callback
                                  // in order to show the dialog
        }catch (Exception e) {
            e.printStackTrace();
    private void formWindowClosing(java.awt.event.WindowEvent evt) {
        try {
            mRegistry.unbind("ICallback");
        }catch (Exception e) {
            e.printStackTrace();
        setVisible(false);
        dispose();
        System.exit(0);
    /** this is the remote callback method, which is invoked from the sevrer */
    public synchronized String askUser() throws java.rmi.RemoteException {
        System.out.println("askUser() thread group: " + Thread.currentThread().getThreadGroup());
        System.out.println("callback started...");
        try {
            SwingUtilities.invokeLater(new Runnable() {
                public void run() {
                    System.out.println("My event started...");
                    JOptionPane.showConfirmDialog(parentFrame, "Are you OK?", "Question", JOptionPane.YES_NO_OPTION);
                    System.out.println("My event finished.");
        }catch (Exception e) {
            e.printStackTrace();
        try {
            Thread.currentThread().sleep(10000);
        }catch (Exception e) {
            e.printStackTrace();
        System.out.println("callback finished.");
        return "Yo!"; // just return anything
     * @param args the command line arguments
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                Client client = new Client();
                client.setSize(500,300);
                client.setVisible(true);
    // Variables declaration - do not modify
    private javax.swing.JButton btDoSomething;
    private javax.swing.JPanel secondTestPanel;
    // End of variables declaration
1_build.bat
javac -cp . -d . *.java
rmic callbackdialog.ServerImpl
rmic callbackdialog.Client
pause
2_RunRmiRegistry.bat
rmiregistry
pause
3_RunServer.bat
rem java -classpath .\ Server
java callbackdialog.Server
pause
4_RunClient.bat
java callbackdialog.Client
pause
######### END CODE ####################################

I can understand that only partially, because SwingUtilities.invokeLater puts(redirects) my runnable object directly into AWT thread. The only conclusion I can draw from all things that I have tried until now , is that SwingUtilities.invokeLater(<showing the dialog>) invoked from a RMI thread somehow have lower "priority" than events coming directly from the AWT-thread and therefore it is held back until normal awt event completes (in this case BUTTON_RELEASED).
But what I don't understand is the fact that the dialog is not shown even If I create and start a new thread from the client's constructor. This thread has nothing to do with RMI as it is in the main thread group:
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    private BlockingObject blocker = new BlockingObject();
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        initComponents();
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                try {
                    dialogBlocker.sleep(0);
                    System.out.println("My event started...");
                    JOptionPane.showConfirmDialog(parentFrame, "Are you OK?", "Question", JOptionPane.YES_NO_OPTION);
                    blocker.wake();
                    System.out.println("My event finished.");
                }catch (Exception e) {
                    e.printStackTrace();
        }).start();
        ...Callback is then only used to wake up this thread which should display the dialog:
    public Object askUser() throws java.rmi.RemoteException {
        System.out.println("callback started...");
        dialogBlocker.wake();
        blocker.sleep(0);
        System.out.println("callback finished.");
        return userChoice; // return anything I don't care for now
class BlockingObject {
    public void sleep(long timeout) {
        synchronized(this){
            try {
                wait(timeout);
            }catch (InterruptedException e) {}
    public void wake() {
        synchronized(this){
            notifyAll();
    }In this case the dialog is shown, but it is NOT painted, so I have deadlock again. Why it is not painted?!?
Haven't I uncouple it from RMI-Thread?
But perhaps I'm looking at the wrong side of the whole thing.
If I invoke server.doSomething (as ejp proposed) in a separate thread, then everything is fine (except that I cannot use this solution in my project :-( ).
It seems that the whole problem is NOT AT ALL related to callback itself, but rather to the fact that if client invokes remote call, even dialogs can't be shown until the rmi call returns to the client.
Thank you, Drindilica

RMI callback with JAVA1.5

Since the version 1.5 we have no need to distribute the stub to all the clients.
It's a great feature, but I need to perform a callback from the server to the client, in this case I need to perform a call to UnicastRemoteObject.exportObject() client-side before calling the registration method exposed by the server, and the stub of the class implementing the callback interface must be placed in the classpath of the server, is it true? Is there any other methos to perform an RMI-callback?
To be clear as much as possible I have this interface exposed by the server
public interface Services extends Remote
public Map<String, ApplicationStatus> applicationsList () throws RemoteException;
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public ApplicationStatus stopApplication (String identifier) throws RemoteException;
public int exitCode (String identifier) throws RemoteException;
   * This method, as the name says, is used by the client to register the listener to some server-side event.
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public void registerForNotification (ExitCodeCallback callback) throws RemoteException;
}and the interface of the callback is
public interface ExitCodeCallback extends Remote
public void notifyExitCode (ExitCodeEvent event) throws RemoteException;
}On the server side I export the services in the registry
Services servicesServerSide = new MyServices();
Services services = (Services) UnicastRemoteObject.exportObject(servicesServerSide , 0);and on the client I perform a lookup of the services
Registry registry = LocateRegistry.getRegistry("192.168.0.1", 1099);
Services services = (Services) registry.lookup("SERVICES");I export my implementation of the interface
public class ClientExitCodeCallback implements ExitCodeCallback
public void notifyExitCode (ExitCodeEvent event)
    System.out.println(event.asString());
}through the code
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java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
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     java.lang.ClassNotFoundException: it.sogei.jscheduler.rmi.client.ClientExitCodeCallback_Stub
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     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:466)
     at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:707)
     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:126)
     at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:179)
     at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:132)
     at $Proxy0.registerForNotification(Unknown Source)
     at it.sogei.jscheduler.rmi.client.StartClient.main(StartClient.java:45)
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     java.lang.ClassNotFoundException: it.sogei.jscheduler.rmi.client.ClientExitCodeCallback_Stub
     at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:285)
     at sun.rmi.transport.Transport$1.run(Transport.java:153)
     at java.security.AccessController.doPrivileged(Native Method)
     at sun.rmi.transport.Transport.serviceCall(Transport.java:149)
     at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:466)
     at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:707)
     at java.lang.Thread.run(Thread.java:595)
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     at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
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     at java.rmi.server.RMIClassLoader$2.loadClass(RMIClassLoader.java:620)
     at java.rmi.server.RMIClassLoader.loadClass(RMIClassLoader.java:247)
     at sun.rmi.server.MarshalInputStream.resolveClass(MarshalInputStream.java:197)
     at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1544)
     at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1466)
     at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1699)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1305)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:348)
     at sun.rmi.server.UnicastRef.unmarshalValue(UnicastRef.java:290)
     at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:279)
     ... 6 moreIs it true all of the above?

If the server gets that exception, it's because the client found and used the stub when it exported its callback, or else the server is running < 1.5.
If the client explicitly cites a port number or zero and it is running >= 1.5 and there is no stub class, it won't use it; it will create a dynamic stub class; and it will send an object of that class to the server as a parameter to the registration call. If the server is running >= 1.5, it will succesfully deserialize that object, reconstruct the dynamic stub from information in the serialization stream, and execute the registration method implementation.
If the client exports by using a stub class instead of the above, it will create an object of that class and send it to the server as a parameter to the registration call; the server will try to deserialize it; and if it doesn't have the stub class available it will throw that exception.
This is how it works.

RMI Callback Applet Tomcat!

Hello,
First timer here...bear with me.
I am running a RMI server and an applet with one interface for the RMI Server. This part works fine. The .class files and the html is deployed thru TOMCAT 4.1
The problem is however when the server code is changed to handle callbacks with the applet. Have already changed the security policy file. Now the applet too has its own interface.
Compiled the .java files and also rmic applet and rmic server. Started the registry after that. And the server too with the codebase too mentioned with -Djava.rmi.server.codebase. (As in the HelloWorld example on the sun website) So far so good.
However as soon as I load the appletviewer as http://localhost:8080/page.html (As I am running Tomcat) the error I get is:
IO Exception while reading: Connection refused: connect
Is it something to do with firewalls? But then everything is right now local and am lost...Any help will be really appreciated. Thanks a bunch.

More explanation to the mentioned problem:
I am sorry for not being very clear on this. Hope this helps.
This link has the "QuoteServer" example which is on the same lines as my project.
http://engronline.ee.memphis.edu/advjava/Examples/RMI/rmi_example.htm
In the above example I compile all four files and then generate rmic for applet and server. Then I place all the class files and the related html for the applet in TOMCAT.
Policy file:
grant {
// Allow everything for now
permission java.security.AllPermission;
permission java.net.SocketPermission "*:1024-65535", "connect,accept";
permission java.net.SocketPermission "*:80", "connect";
Then I start my TOMCAT and then the server with codebase=http:\\localhost:8080\(my folder)\ and the security file as mentioned above. So far so good.
The problem occurs when I start my applet as
appletviewer -J-Djava.security.policy="above file here" http:\\localhost:8080\page.html
Also when I loaded the applet in IE I got the AccessControlException:access denied. Can you also direct me as to how to direct the above security policy file in IE?
Thanks in advance for your patience. I hope I am clearer this time. Please let me know if more details are required.
Appreciate your help.

RMI Callback questions

Hello everybody,
1. Can i have a RMI callback mechanisms established between WLS5.1 and WLE5.0.x..xx
environments?
2. What are the problems associated with it? Any rule of thumb please
3. I need to access EJB's on the WLS side of it,(once hte callback is invoked
by the server) and at the server side, the RMI Server is a daemon looking on the
tuxedo bus using JOLT API's? Any constraints in this approach from BEA Perspective?
Please let me know. It's urgent.
with regds
siva

"siva" <[email protected]> writes:
1. Can i have a RMI callback mechanisms established between WLS5.1 and WLE5.0.x..xx
environments?
2. What are the problems associated with it? Any rule of thumb please
3. I need to access EJB's on the WLS side of it,(once hte callback is invoked
by the server) and at the server side, the RMI Server is a daemon looking on the
tuxedo bus using JOLT API's? Any constraints in this approach from BEA Perspective?I know it can be done using Jolt, I don't know what the limitations are.
andy

RMI Callback with Applet

Hi,
I have a simple RMI Callback Client/Sever Application, where the client-side is inplemented in a JApplet. All works fine by local tests (client and server on my machine), but when the client is on remote machine I got an security exception or error (ClassFormatError(Bad magic number)).
How can I make my client/server work?

No, I'm testing inside LAN, no firewalls, no proxys, no nothing. Just a server and the client (applet).
And this strange error, I'll paste the entire stack trace:
java.lang.ClassFormatError: Client (Bad magic number)
at java.lang.ClassLoader.defineClass0(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at sun.applet.AppletClassLoader.findClass(Unknown Source)
at sun.plugin.security.PluginClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadCode(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
On my local machine oll works fine... is the problem the applet's "sandbox"? Or...?
Any ideas are welcome
Thanks

RMI Callback ConnectException

Hi,
I'm trying to get a RMI Callback running on 2 different machines. The client registers itself at the server who then calls a method on the client. Locally everything works fine, but when running the server on a different PC I get a ConnectException when trying to call the callback method on the client. Funnily enough, the IP to which the connection is refused is that of the server! Why does it try to connect to itself? No firewalls involved, policies okay, registry running... Tested already with two machines running the same OS and Java version.
What am I missing?
Thanks a lot!

I'm also facing the same problem. The application without callbacks runs without problem in one machine AND two different machines. but when i run those on different machines the app with callbacks fails. In this case the client program gives error. The IP address it looks to connect is correct in my case.
Lookup completed
Server said hello
Exception in CallbackClient: java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.ConnectException: Connection refused to host: 192.168.0.199; nested exception is:
java.net.ConnectException: Connection refused

Ports and IPs to be open/permitted in firewall to download and work in creative cloud

What is the complete list of ports and IP addresses to be open/permited in our enterprise firewall in order to let internal PCs download and work with creative cloud applications?

Our firewall only supports IP configuration (not URL). Do you have IP list?
From: Rajshree [email protected]
Sent: miércoles, 06 de noviembre de 2013 17:23
To: Simon, Mariano
Subject: Ports and IPs to be open/permitted in firewall to download and work in creative cloud
Re: Ports and IPs to be open/permitted in firewall to download and work in creative cloud
created by Rajshree <http://forums.adobe.com/people/Rajshree> in Adobe Creative Cloud - View the full discussion <http://forums.adobe.com/message/5819892#5819892

NAPT Firewall, RMI Callbacks and JRMP MultiplexProtocol

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