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Java DatagramSocket problem

gplana
gplana asked
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Last Modified: 2012-05-10
I have an application which sends a DatagramPacket to another by using a DatagramSocket. The sending application has a loop which gets a data from user (2 bytes) and then sends it to the receiving application. The receiving application has a loop which gets data from the DatagramSocket and prints it to console.

First packet is sended ok and showed to console by the receiver. However, after that, when receiver repeats the loop, the instruction dg.receive(p); doesn't seems to keep wainting until new data is received.

This is the code on the receiver:

                  dg = new DatagramSocket(port);
                  while(true)
                  {
                        p = new DatagramPacket(buf,2);
                        dg.receive(p);
                        buf = p.getData();
                        nvia = buf[0];
                        if ((nvia <= nvies) && (nvia>0))
                              vies[nvia-1] = buf[1];
                        
                        // Mostro l'estat de les vies
                        System.out.println("\n\n\n");
                        System.out.println("Estat de les vies");
                        System.out.println("-----------------");
                        for (nvia=1; nvia<=nvies; nvia++)
                              System.out.println("Via " + nvia + ":" + vies[nvia-1]);
                  }
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Author

Commented:
The error message that appears on the client is:
No buffer space available (maximum connections reached?): Cannot bind

The server seems to enter to an infinite looping without waiting for data to arrive.
Tomas Helgi JohannssonDatabase Administrator / Software Engineer
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Commented:
        Hi!

Take a look at this example on how to read/write a DataGramPacket through DataGramSocket.
http://www.java2s.com/Code/Java/Network-Protocol/ReadandwritewithDatagramPacket.htm

Remember to close the socket after sending/receiving the data to allow other connections to
be established.

Regards,
    Tomas Helgi
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Author

Commented:
Thank you. Just a question: if I want a loop which sends a message on every iteration on the loop,  should I close and open again or can I maintain the datagramsocket open for all messages and close at the end of the program ?
Database Administrator / Software Engineer
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Commented:
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Commented:
Thank you very much.

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