Java and Sockets

ID:152781
 
Oct 17 2005, 1:37 pm
Anyone here familiar with the way Java handles sockets and what not. I can not seem to be able to send binary over sockets. I was using PHP to send data to the Byond world using sockets and it works fine. However I am having trouble duplicating in java. I always get the (hit enter to continue) returned. I have tried almost anything to send the hex and or binary values over in a byte like I do in php. But its getting converted to a number or a string and wont send it properly. So if anyone knows how to send the data over java I would be very thankful.
Oct 17 2005, 7:10 pm
Sockets are basically the same everywhere. If you post some code I'll have a look at it.
Oct 18 2005, 10:48 am
In response to Crispy
 
import java.io.*;
import java.net.*;

public class EchoClient {
    public static void main(String[] args) throws IOException {

        Socket echoSocket = null;
        PrintWriter out = null;
        BufferedReader in = null;
      DataOutputStream test = null; 

        try {
            echoSocket = new Socket("127.0.0.1", 2323);

            out = new PrintWriter(echoSocket.getOutputStream(), true);
        test = new DataOutputStream(echoSocket.getOutputStream());

            in = new BufferedReader(new InputStreamReader(echoSocket.getInputStream()));
        } catch (UnknownHostException e) {
            System.err.println("Don't know about host: taranis.");
            System.exit(1);
        } catch (IOException e) {
            System.err.println("Couldn't get I/O for "
                               + "the connection to: taranis.");
            System.exit(1);
        }

    BufferedReader stdIn = new BufferedReader(
                                   new InputStreamReader(System.in));
    test.writeChar(0x00);
    test.writeChar(0x83);
    test.writeChar(0x15);
    test.writeChar(0x00);
    test.writeChar(0x00);
    test.writeChar(0x00);
    test.writeChar(0x00);
    test.writeChar(0x00);
    test.writeBytes("Hey Byond World");
    test.writeChar(0x00);
    test.flush();

    



    if(false)
    {
        out.close();
        in.close();
        stdIn.close();
        echoSocket.close();
    }
    }
}


I have tried all the different outputs but I can not send the correct data over Byond. Heh with PHP I managed it, and I can send java and php to each other.. but... the problem is I cant get java to send the hex or bytes to byond.
Oct 18 2005, 9:41 pm
In response to DoOmBringer
Firstly, the length of the message should be represented using 2 bytes, not 1. Secondly, the length of the message is not 0x15; it's 15. There's a difference. You either need to put 15, or 0x0F (which is 15 written in hexadecimal format).

    test.writeChar(0x00);
    test.writeChar(0x83);
    test.writeChar(0x00); // You missed out this line
    test.writeChar(15); // This line was wrong
    test.writeChar(0x00);
    test.writeChar(0x00);
    test.writeChar(0x00);
    test.writeChar(0x00);
    test.writeChar(0x00);
    test.writeBytes("Hey Byond World");
    test.writeChar(0x00);
    test.flush();
Oct 19 2005, 4:30 pm
In response to Crispy
The length of the message is actually 21 bytes.. Hey Byond World + the 5 bytes before and the 1 byte following it. At least thats how it works in the PHP version. Thanks for the help though, I think Im getting closer to getting it to work.
Oct 19 2005, 4:38 pm
In response to DoOmBringer
Alright its working now. The only thing missing was the empty byte before the length. Thanks alot Crispy, now I start development on my "secret" project heh.
Oct 20 2005, 11:59 am
Heh. wow, I did the same thing 2 months ago, I actually successfuly got it to send and receive messages from byond, I was planning on making BYOND worlds compatible with my Java games, so you can play byond games as a java applet. heh. almost got it working too.