How to get server message correctly

问题

Problem

I send the message "12345" from the socket server to the client:

myPrintWriter.println("12345");

After that I read this message on client:

int c;
while ((c = inputStream.read( )) != -1)
{
    byte[] buffer2 = new byte[1];
    buffer2[0] = (byte) c;
    String symbol = new String(buffer2 , "UTF-8");
    String symbolCode = Integer.toString((int)buffer2[0]);
    Log.v(symbol, symbolCode);
}
Log.v("c == -1", "Disconnected");

What I see in log:

With

out.println("abcrefg");

Why? I think it's line termination symbol. I need to get string "12345" or any other and next strings correctly. Help me please.

If I use bufferedReader.readLine():

try 
{
    byte[] b1 = new byte[1];
    int dataInt = clientSocket.getInputStream().read();
    b1[0] = (byte)dataInt;

    final String data;
    if(dataInt == -1)
        connectionIsLost();

    if(dataInt != -1)
    {
        String c = new String(b1, "UTF-8");
        data = c + inToServer.readLine();
    }
    else
        data = inToServer.readLine();

    if (data != null)
    {
        Log.v("data", data);
        runOnUiThread(new Runnable()
        {
            //data parsing
        });
    }
} 
catch (IOException e){...}

If I send messages slow:

> V/data(5301): -3#Leo#alone in the dark 11-12
> V/message(5301): Leo: alone in the dark 11-12
> V/data(5301): -3#Leo#cgh 11-12 
> V/message(5301): Leo: cgh 11-12 
> V/data(5301): -3#Leo#c
> V/message(5301): Leo: c 11-12 
> V/data(5301): -3#Leo#x 11-12 
> V/message(5301): Leo: x
> V/data(5301): -3#Leo#d 11-12
> V/message(5301): Leo: d

But if I do it faster:

> V/data(5512): -3#Leo#fccc
> V/message(5512): Leo: fccc
> V/data(5512): -3#Leo#ccc
> V/data(5512): -3#Leo#cccc
> V/message(5512): Leo: ccc
> V/message(5512): Leo: cccc
> V/data(5512): --3#Leo#cccc //<-----error
> V/data(5512): 3-3#Leo#cccc //<-----error
> V/data(5512): #Leo#xdd

Exception :(

回答1:

Have in mind the UTF-8 enconding may result in more than one byte per character, and your code above will fail to correctly handle them.

If you want to read String encoded in UTF-8, is better to have them decoded by a ´BufferdReader` and getting it line by line.

Example code:

    String line;
    BufferedReader _in = new BufferedReader(new InputStreamReader(_socket.getInputStream(),"UTF-8"));

    try {
         while ((line = _in.readLine()) != null) {
            Log.d(TAG, line);
         }
         Log.d(TAG, "Connection is closed");
    } catch (Exception e) {
         Log.d(TAG, "Connection is closed");
    }

Regards.

回答2:

Definitely it is CR/LF. It is there because you are using println. Try print instead.

来源：https://stackoverflow.com/questions/13359049/how-to-get-server-message-correctly

标签

android

sockets

inputstream