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Callback calls instead of real client IP  RSS feed

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Hi all, I'd like to ask a question.. it may sound easy but I'm stuck with it.
I have successfully implemented a callback architecture in my program, but it works only if the server and client programs are on the same machine. If I load the client on another machine the client can call any rmi method on the server, but when it's time to use a callback method the server tries to connect to
Should I set java.hostname property also on the client? I don't think so, but never say never..

simplified versions of the sources:

Log of the server console:

java.rmi.ConnectException: Connection refused to host:; 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.invoke(UnicastRef.java:110)
at Root.Dominio.ServerDelegate_Stub.printMessage(ServerDelegate_Stub.java:55)
at Root.Rmi.RmiDelegate.printRemotely(RmiDelegate.java:116)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:305)
at sun.rmi.transport.Transport$1.run(Transport.java:159)
at java.security.AccessController.doPrivileged(Native Method)
at sun.rmi.transport.Transport.serviceCall(Transport.java:155)
at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:535)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:790)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:649)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)
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:366)
at java.net.Socket.connect(Socket.java:519)
at java.net.Socket.connect(Socket.java:469)
at java.net.Socket.<init>(Socket.java:366)
at java.net.Socket.<init>(Socket.java:180)
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)
... 19 more

Scripts I use to run the server and the clients:
java -Djava.security.policy=security.policy -jar Client.jar

java -Djava.security.policy=security.policy -Djava.rmi.server.hostname= -Djava.rmi.server.codebase=file:/home/Server/Client.jar -jar Server.jar

Can somebody figure out what's wrong in my code?
Thanks in advance, Andrea.
Andrea Guarini
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I should have set the hostname property also on the client...
I thought the UnicastRemoteObject.exportObject told the server everything it needed to call the clients.
If I have a client which runs on dhcp how should I set this property?
Now I'm in a LAN setting, so I simply put the local IP address of my client machine. Should I put the public IP address?
Ranch Hand
Posts: 67
Debian Eclipse IDE Java
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Normally a client also has a name on the network you could use that in the property (e.g. client.local). I hope this helps.
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1) host = "192.168...."
2) hostName = InetAddress.getByName(host).getHostAddress();

1) System.setProperty("java.rmi.server.hostname", host);
2) System.setProperty("java.rmi.server.hostname", hostName);
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