sender_01.java

codigo fuente de protocolo ARQ stop and wait (IDLE ARQ)

package ece544.p1.zbwu;

import java.io.IOException;
import java.io.InputStream;

import ece544.p1.ISender;
import edu.rutgers.winlab.labloma.net.*;


/**
 * Zhibin Wu, 
 * [e-mail] 
 *
 * Implementation of the IReceiver 
 */
public class 
Sender 
	implements ISender
{
	/**
	 * define private variables here
         * sending buffer is 1024 bytes
         * assgin the port to local defaultport variable
	 */
        private INetworkPort defaultport;
        private byte[] in;
	public 
	Sender(
		INetworkPort port
	) {
             defaultport = port ;
             in = new byte[1024];

	}

	/**
	 * @see ece544.p1.ISender#send(InputStream, IAddress)
         * 
         * The method is simple, reading 1020 bytes from the inputstream
         * to the buffer in[1024]
         * initilzie last 4 bytes as buffer as "0000", then fill
         * the 4 bytes as length indicator, becasue the length is at most
         * 1020, thus, 4 character is enough
         * Then, use the "send" functin provide by port to sending those
         * 1024-size packets out of the networkport.
         *
	 */
	public void 
	send(
		InputStream stream, 
		IAddress addr
	) throws IOException 
	{
            int i;
            int j;
            int len_str;

            while ( (j=stream.read(in,0,1020))!= -1)
            {

              String s= Integer.toString (j);
              len_str = s.length();
	      byte[] len = s.getBytes();
              for ( i= 1020; i< 1024; i++ ) in[i] = '0';  
              for ( i= 0; i< len_str; i++) in [1024- len_str + i] = len[i]; 
              defaultport.send (addr, in);
            }            
          

	}

}