Java

Socket Send/Receive 16-bit Integers

Demonstrates sending and receiving 16-bit integers over a socket connection using either big-endian or little-endian byte ordering. Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    //  This example requires the Chilkat API to have been previously unlocked.
    //  See Global Unlock Sample for sample code.

    CkSocket sock = new CkSocket();

    //  --------------------------------------------------------------------
    //  This example uses the public TCP echo service at https://tcpbin.com/
    //  --------------------------------------------------------------------

    boolean useTls = false;
    int port = 4242;
    int maxWaitMs = 5000;
    success = sock.Connect("tcpbin.com",port,useTls,maxWaitMs);
    if (success == false) {
        System.out.println(sock.lastErrorText());
        return;
        }

    //  Wait a max of 2 seconds for a response..
    sock.put_MaxReadIdleMs(2000);

    //  Send a 16-bit integer using big-endian byte ordering (also called network byte order)
    //  12022 decimal = 2EF6 hex
    int value = 12022;
    boolean bigEndian = true;
    sock.SendInt16(value,bigEndian);
    //  Send it again, because we'll read it two different ways..
    sock.SendInt16(value,bigEndian);

    //  The tcpbin.com echo server only echoes after receiving an LF (linefeed char)
    sock.SendByte(10);

    //  Let's see hex values of the 2 bytes sent in network byte order (big-endian)
    //  (The echo server sends back exactly the bytes received.)
    String hexStr = sock.receiveNBytesENC(2,"hex");

    //  In the big-ending byte order, the byte order is most significant byte to least significant,
    //  therefore we should see the bytes in the order 0x2E 0xF6.
    System.out.println("Expecting big-endian 2EF6");
    System.out.println(hexStr);

    //  Let's read directly to an integer..
    success = sock.ReceiveInt16(bigEndian,true);
    System.out.println("Expecting 12022");
    System.out.println("Received: " + sock.get_ReceivedInt());

    //  Consume the LF that gets echoed back..
    sock.ReceiveByte(true);

    //  --------------------------------------------------------------------
    //  Let's do the same thing, but with little-endian byte ordering.

    System.out.println("----");

    //  12022 decimal = 2EF6 hex, but little-endian byte ordering will send the bytes in the order 0xF6 0x2E
    value = 12022;
    bigEndian = false;
    sock.SendInt16(value,bigEndian);
    sock.SendInt16(value,bigEndian);
    sock.SendByte(10);

    hexStr = sock.receiveNBytesENC(2,"hex");

    System.out.println("Expecting little-endian F62E");
    System.out.println(hexStr);

    success = sock.ReceiveInt16(bigEndian,true);
    System.out.println("Expecting 12022");
    System.out.println("Received: " + sock.get_ReceivedInt());

    //  Consume the LF that gets echoed back..
    sock.ReceiveByte(true);

    sock.Close(1000);

    //  Output:

    //  Expecting big-endian 2EF6
    //  2EF6
    //  Expecting 12022
    //  Received: 12022
    //  ----
    //  Expecting little-endian F62E
    //  F62E
    //  Expecting 12022
    //  Received: 12022
  }
}