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Thread: server/client communication problem

  1. #1
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    Default server/client communication problem

    I am confused with my project.

    It is a server/client system which uses java nio.

    The requiremet is that the server keep sending 10 messages to the client. Then the client read messages. But the cilent can read incomplete message which causes exception.

    I have a message size at the beginning of a message. How to let the client read the number of bytes specified in the msgSize.


    how to solve this problem? Thanks.


  2. #2
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    Default Re: server/client communication problem

    What classes and methods are you using?

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    Default Re: server/client communication problem

    For read:
                 n = socket.read(rbuf);
    	     if (((n==0) || (n==-1))) {
    		logger.logInfo("t=" + t + " count=" + count + " and break."); //5-21-11
    		break;
    	     }

    For write:
                  n = socket.write(buffer);
    	      if(n == 0) { 							
    		buffer.clear();
    		break;//Feb14					
    	      }							
    	      count += n;					
    	      if(buffer.hasRemaining()){					
    		buffer.compact();				
    	      }

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    Default Re: server/client communication problem

    How to let the client read the number of bytes specified in the msgSize.
    What class is socket?
    Your code appears to try read rbuf.size number of bytes. Why not read the header and get the message size at the beginning of a message before reading the rest.

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    Default Re: server/client communication problem

    Thank you. But the SocketChannel class just provide method to read a chunk, instead of byte by byte. Is there any way to read the header and get message size first. Then I can read the required amount of bytes. Thanks.

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    Default Re: server/client communication problem

    n = socket.read(rbuf)
    What class is the variable socket that you show in your code sample?

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    Default Re: server/client communication problem

    socket is an instance of SocketChannel.

    If I add an interval between messages, the problem is not there. I just feel that adding an interval may not be a good solution. Is there other ways?

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    Default Re: server/client communication problem

    Sorry, I haven't worked with that.

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    Default Re: server/client communication problem

    thank you.

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