i try to program a part of a university research project about multi client – server socket programming.my code works as well as so that i give valide result but the problem is that evalutor of our group said that my code have not a good speed on connection for data transfer.i will be thankfull if you found the problem(s) in my code that cause this issue.
server part:
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import j
ava.io.PrintStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketAddress;
import java.net.UnknownHostException;
import java.util.ArrayList;
/**
*
*/
/**
* @author Sina
*
*/
public class BoxServer {
ServerSocket serversocket;
static ThreadHandler t[]=new ThreadHandler[100];
static int size=0;
static ArrayList<Message> messagebox=new ArrayList<Message>();
public static void main(String[] args) {
ServerSocket serverSocket = null;
try {
serverSocket = new ServerSocket(79);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
while(true)
{
try{
//InetAddress inetadress=InetAddress.getLocalHost();
//System.out.println(inetadress);
//System.out.println(inetadress.getHostName());
//System.out.println(inetadress.getHostAddress());
Socket socket=serverSocket.accept();
if(socket==null)
{
System.out.println("null");
}
t[size]=new ThreadHandler(socket,"username");
size++;
t[size-1].start();
}
catch(UnknownHostException e){
System.out.println("salam s");
System.out.println(e.getMessage());
}
catch (IOException e) {
System.out.println("bye s");
System.out.println(e.getMessage());
}
}
}
}
class ThreadHandler extends Thread{
private String socname;
Socket mySocket;
ObjectInputStream inp;
ObjectOutputStream outp;
public ThreadHandler(Socket s,String socketName)
{
this.mySocket=s;
this.socname=socketName;
}
public void run()
{
try {
inp=new ObjectInputStream(mySocket.getInputStream());
outp=new ObjectOutputStream(mySocket.getOutputStream());
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
while(true)
{
System.out.println("thread run");
System.out.println(mySocket.getLocalPort());
System.out.println(mySocket.getLocalAddress());
try {
// System.out.println("my socket:"+mySocket.getOutputStream());
System.out.println(mySocket.isConnected());
System.out.println(inp.available());
System.out.println("inp = "+inp);
System.out.println("reeead "+ inp.readObject());
Message mess=(Message)inp.readObject();
System.out.println("dsd");
System.out.println("mess: "+mess);
BoxServer.messagebox.add(mess);
if(mess.getReceiver().equals("system-use:code=1"))
{
System.out.println(mess.getSender()+" wants to see his/her Inbox");
}
//mySocket.close();
} catch (Exception e) {
// TODO Auto-generated catch block
System.out.println("bug dar thread");
e.printStackTrace();
}
}
}
}
client part
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;
import java.util.TimerTask;
import java.util.concurrent.ScheduledExecutorService;
import javax.swing.Timer;
public class Main {
/**
* @param args
*/
static Socket socket=new Socket();
public static void main(String[] args) {
System.out.println("newuser(n) or login(l)");
Scanner scanner=new Scanner(System.in);
String typeOfOperation=scanner.nextLine();
if(typeOfOperation.equals("n"))
{
}
else
if(typeOfOperation.equals("l"))
{
try {
socket = new Socket("127.0.0.1",79);
final ObjectOutputStream out = new ObjectOutputStream(socket.getOutputStream());
ObjectInputStream in=new ObjectInputStream(socket.getInputStream());
while(true)
{
Thread timer=new Thread()
{
public void run()
{
while(true)
{
Message temp=new Message();
temp.setReceiver("system-use:code=1");
temp.setSender("username");
try {
out.writeObject(temp);
sleep(5000);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (InterruptedException e) {
// TODO: handle exception
e.printStackTrace();
}
}
}
};
timer.start();
String username=scanner.nextLine();
String to=scanner.nextLine();
String body=scanner.nextLine();
Message all=new Message();
all.setText(body);
all.setReceiver(to);
all.setSender(username);
System.out.println("you connected to system");
System.out.println(socket);
System.out.println("now should write");
out.writeObject(all);
System.out.println("ghable threAD");
}
// socket.close();
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
System.out.println("salaam c");
System.out.println(e.getMessage());
} catch (IOException e) {
// TODO Auto-generated catch block
System.out.println("bye c");
System.out.println(e.getMessage());
}
}
else
{
System.out.println("bad operation. try again!");
}
}
}
Message class(Entity only not important i think!):
import java.io.Serializable;
public class Message implements Serializable{
String sender;
String receiver;
String text;
boolean delivered=false;
public void delived()
{
this.delivered=true;
}
private String tostringOfClass;
public void setReceiver(String receiver) {
this.receiver = receiver;
}
public void setSender(String sender) {
this.sender = sender;
}
public void setText(String text) {
this.text = text;
}
public String getReceiver() {
return receiver;
}
public String getSender() {
return sender;
}
public String getText() {
return text;
}
public String toString()
{
tostringOfClass="sender : "+sender+" \n"+"receiver : "+receiver+" \n"+"message: "+text;
return tostringOfClass;
}
}
Your evaluator missed something much more important: it doesn’t work. You are calling readObject() twice per loop in the server, but all you do with the first result is print it out with System.out.println(). So your code is missing every odd object.
There isn’t much you could do to improve the speed of this. He probably wants you to interpose a BufferedOutputStream between the ObjectOutputStream and the socket, and similarly for BufferedInputStream. However the object streams already run their own buffers, so this is probably a waste of time. He might also want you to use large socket send and receive buffers, if you’ve been taught about those: see Socket.setXXXBufferSize(). Set them to at least 32k. He might also be anti-Serialization, but for this application I don’t see that it makes much difference. This is an interactive application, and the messages are small, so the speed over the network is basically irrelevant. You can only type so fast.
You should also close in the client when the user types whatever it is that tells the program to stop, and in the server you must catch EOFException, before IOException, and close the socket and break out of the read loop when you get it.
Also printing out Socket.isConnected() yields no useful information. The socket is always connected at the points you print it at. This method is not a health-check for the connection, it only tells you about the state of your Socket. Not the same thing.
Your evaluator seems to me to be focussing on entirely the wrong thing.