How to get data from TCP socket into a ByteBuffer

Question

I need to get incoming data from a socket into a ByteBuffer and I do not know how to do it. I am new to this field and therefore not sure of the best way to start. I found the following but that is not what I want as it gets the data in line but I need to have all of my data in bytebuffer for other purposes.

ServerSocket welcomeSocket = new ServerSocket(Integer.parseInt(ibmPort));
while (true) {
    Socket connectionSocket = welcomeSocket.accept();                   
    BufferedReader inFromClient =  new BufferedReader(new InputStreamReader(connectionSocket.getInputStream()));
    DataOutputStream outToClient = new DataOutputStream(connectionSocket.getOutputStream());
    clientSentence = inFromClient.readLine();
    System.out.println("Received: " + clientSentence);
    setRequestDataFromCT(clientSentence);
    capitalizedSentence = clientSentence.toUpperCase() + '\n';
    outToClient.writeBytes(capitalizedSentence);
}

You should add which language you are using. To me it looks like Java but well I dont know. — clentfort, Sep 18 '12 at 14:19
The code you posted uses Reader interface, which handles human readable strings rather than bytes. Is that what you want? — pmoleri, Sep 18 '12 at 15:48
I want it to handle the incoming string as a byte since there are characters there that can't be cast in string. — user1372020, Sep 18 '12 at 16:18

pmoleri · Accepted Answer · 2012-09-18T16:43:00.813

This code will read all the bytes and store them in a ByteBuffer, you may have to adjust the bufferSize to store all the data you need.

int bufferSize = 8192;
ServerSocket welcomeSocket = new ServerSocket(Integer.parseInt(ibmPort));
while (true) {
    Socket connectionSocket = welcomeSocket.accept();
    ByteBuffer bf = ByteBuffer.allocate(bufferSize);
    BufferedInputStream inFromClient = new BufferedInputStream(connectionSocket.getInputStream());
    while (true) {
        int b = inFromClient.read();
        if (b == -1) {
            break;
        }
        bf.put( (byte) b);
    }
    connectionSocket.close();
}

Many thanks. I also just a minute ago find a similar way. I post it here too as it might be useful. — user1372020, Sep 18 '12 at 16:45

user207421 · Answer 2 · 2012-09-19T22:27:45.293

2

int count = SocketChannel.read(ByteBuffer). Not sure why you added the 'socketchannel' tag if you weren't using SocketChannels, but this is how to do it.

edited Sep 19 '12 at 22:27

answered Sep 18 '12 at 23:59

user207421

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score -1 · Answer 3 · answered Sep 18 '12 at 16:49

-1

        ServerSocket welcomeSocket = new ServerSocket(Integer.parseInt(ibmPort));
        while (true) {
            Socket connectionSocket = welcomeSocket.accept();
            InputStream stream = connectionSocket.getInputStream();
            byte[] data = new byte[1024];
            int count = stream.read(data);
            ByteBuffer bb = ByteBuffer.allocate(data.length);
            bb.put(data);
            bb.flip();
        }

answered Sep 18 '12 at 16:49

user1372020

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12

2

Careful, there's no guarantee that the read method will read all the data at once, it can return with a portion of the data to be received. – pmoleri Sep 18 '12 at 19:29
(-1 if I were allowed) You should not be calling allocate() inside the while loop – Alastair Nov 15 '16 at 21:12

How to get data from TCP socket into a ByteBuffer

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