tcpclient.java

ssd8 exercise 3 Write a simple datagram client/server in Java and a tcp client/server also in java

import java.io.*;
import java.net.*;
import java.util.*;
/* 
 * Created on 2008-4-12
 *
 * TODO To change the template for this generated file go to
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 */

/**
 * @author Guest
 *
 * TODO To change the template for this generated type comment go to
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 */
public class TCPClient {

	/*
	 * Define the default port for the packet send to.
	 */
	private static int defaultPort = 8000;
	
	/*
	 * Define the size of buffer to make sure that one packet contain one byte.
	 */
	private static int bufferSize = 1;
	
	/*
	 * To make sure send-and-echo should be repeated 1000 times.
	 */
	private static int sendTimes = 1000;
	
	 /*
	  * The main(String[]) method.
	  */
	public static void main(String[] args)throws Exception {
	
		/*
		 * Record the current send-and-echo times 
		 */
		int count = 0;
		
		/*
		 * Record the the number of packets lost and duplicated.
         */
		int lostAndDuplicated = 0;
		
		/*
		 * Contain the average round trip time.
		 */
		float avgRtt;
		
		/*
		 * Sign the begining time of the whole send-and echo process. 
		 */
		Date start;
		
		/*
		 * Sign the ending time of the whole send-and echo process. 
		 */
		Date stop;
		
		/*
		 * Declarate the send byte. 
		 */
		byte sendBuffer[] = new byte[bufferSize];
		
		/*
		 * Declarate the receive byte. 
		 */
		byte receiveBuffer[] = new byte[bufferSize];
 
	    /*
	     * The out to server stream.
	     */
		DataOutputStream outToServer;
		
		/*
		 * The input from user stream.
		 */
		DataInputStream inFromUser;
		
		/*
		 * The TCP client socket.
		 */
		Socket clientSocket;
		
		/*
		 * Initial the send byte.
		 */
		sendBuffer[0] = 0;
	
		try{
			
		start = new Date();
		for(count = 0;count < sendTimes;count++)
		{
		clientSocket = new Socket("127.0.0.1",defaultPort);
		clientSocket.setSoTimeout(1000);
		outToServer = new DataOutputStream(clientSocket.getOutputStream());
		inFromUser = new DataInputStream(clientSocket.getInputStream());
		outToServer.write(sendBuffer);
		outToServer.flush();
		inFromUser.read(receiveBuffer);
		 
	    if(sendBuffer[0] != receiveBuffer[0])
		{
			 
			count--;
		 	lostAndDuplicated ++;
			
		}
		if(sendBuffer[0] < 127)
		{
			sendBuffer[0]++;
		}
		else
		{
			sendBuffer[0] = 0;
		}
		 
		clientSocket.close();
		}
		stop = new Date();
		avgRtt = (float)(stop.getTime()- start.getTime())/sendTimes;
		System.out.println("The number of packets lost and duplicated is: " + lostAndDuplicated);
		System.out.println("The average round trip time to send one byte with TCP is: " + avgRtt + " vs");
	}catch (SocketTimeoutException ste) {

			count--;
			
			lostAndDuplicated ++;;
			
	}catch(Exception e){
		
		e.printStackTrace();
		System.err.println("Error!");
		
	}
	}
}