Client Server Email Problem

Atomic Pineapple

Hi,

I'm trying to make a VERY simple email client and server in java and I've hit a bit of a problem.

Here is the code in the client that sends the username to the server

[b]Client[/b] 


if ((message.trim()).equals (endMessage))
            {
               done = true;
               helper.done( );
            }
            else {
            	System.out.println("Enter your username");
            	username= br.readLine();
               if(helper.connect(username) == true)
               {
            	   loggedin = true;
               }

[b]Client Helper[/b]


public boolean connect(String newUser)throws SocketException,
   IOException 
   {
	   String response;
	   System.out.println("HELLO");
	   mySocket.sendMessage(newUser);
	   response = mySocket.receiveMessage();
	   System.out.println("hghg: " + response);
	   System.out.println("HELLO2");
	   if(response.equals("logged in"))
	      {
	    	  return true;
	      }
	   else
	      return false;
   }

This code asks the user to enter a username on the command line

here is the server code

[b]Server[/b] 


public static boolean login(String username)
   {	boolean outcome = false;
	   for(User u : users)
	   {
		   
		   if(u.equals(username))
		   {
			   outcome = true;
		   }
		   else{
			   outcome = false;
		   }}
	   return outcome;
	   
			   
   }

[b]Server Helper[/b]

if ((message.trim()).equals (endMessage)){
	                //Session over; close the data socket.
	/**/            System.out.println("Session over.");
	                myDataSocket.close( );
	                done = true;
	             } //end if
	             
	             else if(message.equals("login")) 
	             {
	                username = myDataSocket.receiveMessage();
	                
	                System.out.println(username);
	                
	                login(username);
	             
	                if(EchoServer3.login(username))
	                {
	                	myDataSocket.sendMessage("logged in");
	                }
	                else
	                {
	                	myDataSocket.sendMessage("login failed");
	                }

When I input a username on the command line, it gets as far as the first HELLO print statement but then nothing appears afeter that, I was wondering if anyone can spot an error anywhere in the code

Thanks in advance

lynchie

Well either your sendMessage call is not returning or your receiveMessage method is blocking waiting on a reply. Too hard to tell without seeing the code in its entirety.

Atomic Pineapple

lynchie wrote: »

Well either your sendMessage call is not returning or your receiveMessage method is blocking waiting on a reply. Too hard to tell without seeing the code in its entirety.

yep, I figured it was a missing recieve or send, cant seem to work it out at all, heres the entire code if anyone wants to glance over it, it doesnt really matter

Client

package Client;
import java.io.*;
import java.util.Vector;

import object.EmailObject;


public class EchoClient2 {
   static final String endMessage = ".";
   public static void main(String[] args) {
      InputStreamReader is = new InputStreamReader(System.in);
      BufferedReader br = new BufferedReader(is);
      
      String response = "";
      String username = "";
      
      
      try {
         System.out.println("Welcome to the Echo client.\n" +
            "What is the name of the server host?");
         String hostName = br.readLine();
         
         
         if (hostName.length() == 0) // if user did not enter a name
            hostName = "localhost";  //   use the default host name
         System.out.println("What is the port number of the server host?");
         String portNum = br.readLine();
         
         
         if (portNum.length() == 0)
            portNum = "1013";          // default port number
         EchoClientHelper2 helper = 
            new EchoClientHelper2(hostName, portNum);
         boolean done = false;
         boolean connected = false;
         boolean loggedin = false;
         String message, echo, option;
         
         
         if (!connected) {
            System.out.println("Enter login, or a single period to quit.");
            message = br.readLine( );
            if ((message.trim()).equals (endMessage))
            {
               done = true;
               helper.done( );
            }
            else {
            	System.out.println("Enter your username");
            	username= br.readLine();
            	System.out.println(username);
            	System.out.println(helper.connect((username)));
            	System.out.println("here");
               if(helper.connect(username))
               {
            	   loggedin = true;
            	   connected = true;
               }
               else if(connected)
            {
            	System.out.println("Enter 'send', 'read' or '.'");
            	message = br.readLine();
            	if ((message.trim()).equals (endMessage))
                {
                   done = true;
                   helper.done( );
                }
            	else if(message.equals("send"))
            	{
            		System.out.println("Enter the reciever");
            		String reciver = br.readLine();
            		
            		
            		System.out.println("Enter the message");
            		String body = br.readLine();
            		response = helper.sendMessage(reciver, username, body);
            		System.out.println(response);
            		
            	}
            	else if(message.equals("read")) {
            		Vector<EmailObject> r = helper.getUnreadMsgs(username);
            		
            		for(EmailObject v : r) {
            			System.out.println(v.getSender());
            			System.out.println(v.getReciever());
            			System.out.println(v.getMessage());
            		}
            	}
            			
            		
            			
            }
            
            
         
         } 
      }} // end try  
      catch (Exception ex) {
         ex.printStackTrace( );
      } //end catch
   } //end main
   
} // end class

Client Helper

package Client;
import java.net.*;
import java.util.Vector;
import java.io.*;

import object.EmailObject;




public class EchoClientHelper2 {

   static final String endMessage = ".";
   private MyStreamSocket mySocket;
   private InetAddress serverHost;
   private int serverPort;
   
   private static BufferedReader in, userEntry;
   private static PrintWriter out;
   private static String name;
   

   EchoClientHelper2(String hostName,
                     String portNum) throws SocketException,
                     UnknownHostException, IOException {
	    userEntry = new BufferedReader(new InputStreamReader(System.in));
	    in = new BufferedReader(new InputStreamReader(System.in));
  	    this.serverHost = InetAddress.getByName(hostName);
  		this.serverPort = Integer.parseInt(portNum);
      
   	this.mySocket = new MyStreamSocket(this.serverHost,
         this.serverPort); 
/**/  System.out.println("Connection request made");
   } // end constructor
	
   public String getEcho( String message) throws SocketException,
      IOException{     
      String echo = "";    
      mySocket.sendMessage( message);
	   
      echo = mySocket.receiveMessage();
      return echo;
   } 

   public void done( ) throws SocketException,
                              IOException{
      mySocket.sendMessage(endMessage);
      mySocket.close( );
   } // end done 
   
   public boolean connect(String newUser)throws SocketException,
   IOException 
   {
	   String response = "";
	   mySocket.sendMessage("login");
	   System.out.println("HELLO");
	   System.out.println("hghg: " + response);
	   System.out.println("hghg: " + newUser);
	   mySocket.sendMessage(newUser);
	   System.out.println("hghg324234: " + newUser);
	   response = mySocket.receiveMessage();
	   System.out.println("hghg: " + response);
	   System.out.println("HELLO2");
	   if(response.equals("logged in"))
	      {
	    	  return true;
	      }
	   else
	      return false;
   }
   
   public String sendMessage(String reciever, String sender, String text) throws IOException
   {
	   System.out.println("send message");
	   mySocket.sendMessage("sendMessage");
	   
	   mySocket.sendMessage(reciever);
	   mySocket.sendMessage(sender);
	   mySocket.sendMessage(text);
	   
	   
	   return mySocket.receiveMessage();
   }

   public Vector getUnreadMsgs(String user) throws IOException {
	   
	   
	   mySocket.sendMessage("getUnreadMsgs");
	   
	   Vector<EmailObject> emails = new Vector<EmailObject>();
	   EmailObject m = new EmailObject();
	   int loops = Integer.parseInt(mySocket.receiveMessage());
	   
	   for (int i = 0; i < loops; i++){
		   String to = mySocket.receiveMessage();
		   String from = mySocket.receiveMessage();
		   String bodytext = mySocket.receiveMessage();
		   
		   m.setReciever(to); 
		   m.setSender(from);
		   m.setMessage(bodytext);
		   
		   emails.add(m);
	   }
	   
	   ;
	   return emails;
   }

   
} //end class

Server

package Server;
import java.io.*;
import java.net.*;
import java.util.Vector;

import object.EmailObject;
import object.Inbox;
import object.User;





import Client.MyStreamSocket;



public class EchoServer3 
{
	static User u = new User("donal");
	
	private static Vector<Inbox> inboxes = new Vector<Inbox>();
	private static Vector<User> users = new Vector<User>();
	
   public static void main(String[] args) 
   {
	   
	   Inbox draffod = new Inbox("draffod");
	   Inbox aocon = new Inbox("aocon");
	   EmailObject m = new EmailObject("draffod", "aocon");
	   
	   aocon.addMessage(m);
	   
	   inboxes.add(aocon);
	   inboxes.add(draffod);
	   users.add(u);
	   
	   
	   
      int serverPort = 1013;    
      String message;

       
      try {
         
   	   ServerSocket myConnectionSocket = 
            new ServerSocket(serverPort); 
     System.out.println("Message server ready.");  
         while (true) {  // forever loop
                 System.out.println("Waiting for a connection.");
            MyStreamSocket myDataSocket = new MyStreamSocket
                (myConnectionSocket.accept( ));
        System.out.println("connection accepted");
         message = myDataSocket.receiveMessage();
         System.out.println(message);
         if(message == "login"){
        	 
        	 System.out.println("login Recieved");
        	 
         }
            
            Thread theThread = 
               new Thread(new EchoServerThread(myDataSocket));
            theThread.start();
            
            // and go on to the next client
            } //end while forever
       } // end try
	    catch (Exception ex) {
          ex.printStackTrace( );
	    } // end catch
   } //end main
   
   public static boolean login(String username)
   {	boolean outcome = false;
	   for(User u : users)
	   {
		   
		   if(u.equals(username))
		   {
			   outcome = true;
		   }
		   else{
			   outcome = false;
		   }}
	   return outcome;
	   
			   
   }
  
   public static Boolean addToInbox(EmailObject m)
   {
	   System.out.println("In server add to inbox");
	   String reciever =  m.getReciever();
	  for(Inbox i : inboxes)
	  {
		  if(i.equals(reciever))
		  {
			  
			  return true;
		  }
			   
	  }
	  return false;
   }
   
   public static Vector<EmailObject> getMessages(String userName)
   {
	   Vector<EmailObject> unread = new Vector<EmailObject>();
	   int c = 0;
	   for(Inbox i : inboxes)
	   {
			  if(i.equals(userName))
			  {
				  
				  
				 break;
			  }
			  else
			  {
				  c++;
			  }
	   }
   
	   
	   Inbox box = inboxes.get(c);
	   
	   Vector<EmailObject> messages = box.getMessages();
	   
	   int o = 0;
	   for(EmailObject m : messages)
	   {
		   
			   unread.add(m);
		   
			o++;
	   }
	   System.out.println("unread size: " + unread.size());
	   return unread;
	   
	   
   }
   
   
} // end class

Server Helper

package Server;

import java.util.ArrayList;
import java.util.Vector;

import object.EmailObject;
import object.Inbox;
import object.User;


import Client.MyStreamSocket;

class EchoServerThread implements Runnable {
	   String username;
		static final String endMessage = ".";
	   MyStreamSocket myDataSocket;
	   
	   EchoServerThread(MyStreamSocket myDataSocket) {
	      this.myDataSocket = myDataSocket;
	   }
	 
	   public void run( ) {
	      boolean done = false;
	      String message;
	      try {
	             message = myDataSocket.receiveMessage( );
				
	             if ((message.trim()).equals (endMessage)){
	             
                    System.out.println("Session over.");
	                myDataSocket.close( );
	                done = true;
	             } 
	             
	             else if(message.equals("login")) 
	             {
	            	 System.out.println("gets to here.");
	                username = myDataSocket.receiveMessage();
	                System.out.println("gets to here two.");
	                System.out.println(username);
	                
	                login(username);
	             
	                if(EchoServer3.login(username))
	                {
	                	myDataSocket.sendMessage("logged in");
	                }
	                else
	                {
	                	myDataSocket.sendMessage("login failed");
	                }
	                	
	               
	             }
	             
	             message = myDataSocket.receiveMessage( );
	             if(message.equals("sendMessage"))
	             {
	            	System.out.println("In thred send message");
	            	String sender = myDataSocket.receiveMessage();
	            	String body = myDataSocket.receiveMessage();
	            	
	            	
	                
	               
	            	
	            	EmailObject m = new EmailObject( sender, body);
	            	if(EchoServer3.addToInbox(m))
	            	{
	            		myDataSocket.sendMessage("MessageSent");
	            		
	            	}
	            	else
	            	{
	            		myDataSocket.sendMessage("MessageFailed");
	            	}
	             }
	             
	             //message = myDataSocket.receiveMessage( );
	             if(message.equals("getUnreadMsgs"))
	             {
	            	 Vector v = EchoServer3.getMessages(username);
	            	 EmailObject mm = new EmailObject();
	            	 
	            	 String loops = Integer.toString(v.size());
	            	 myDataSocket.sendMessage(loops);
	            	 
	            	 for (int i = 0; i < v.size(); i++) {
	            		 mm = (EmailObject) v.get(i);
	            		 
	            		 myDataSocket.sendMessage("From: " + mm.getReciever());
	            		 myDataSocket.sendMessage("Body: " + mm.getMessage());
	            	 }
	            	 
	             }
	          
	        }// end try
	        catch (Exception ex) {
	           System.out.println("Exception caught in thread: " + ex);
	        } // end catch
	   } //end run

		public boolean login(String username)
		{
			return EchoServer3.login(username);
		}
			
	} //end class 

I'll post it up if i get it myself

lynchie

Dont see the implementation of MyStreamSocket anywhere? I assume its based on standard java Scokets, so I guess you are using standard IO streams to read write from the sockets? I assume you are flushing the buffers after writing data to them?

Atomic Pineapple

lynchie wrote: »

Dont see the implementation of MyStreamSocket anywhere? I assume its based on standard java Scokets, so I guess you are using standard IO streams to read write from the sockets? I assume you are flushing the buffers after writing data to them?

sorry i left it out to keep the post a bit shorter, yeh using standard streams

here is the code

import java.net.*;
import java.io.*;

public class MyStreamSocket extends Socket {
   private Socket  socket;
   private BufferedReader input;
   private PrintWriter output;

   private InetAddress ipaddress;

   MyStreamSocket(InetAddress acceptorHost,
                  int acceptorPort ) throws SocketException,
                                   IOException{
      socket = new Socket(acceptorHost, acceptorPort );
      setStreams( );
      setLocationInfo();

   }

   public MyStreamSocket(Socket socket)  throws IOException {
      this.socket = socket;
      setStreams( );
      setLocationInfo();
   }

   private void setStreams( ) throws IOException{
      // get an input stream for reading from the data socket
      InputStream inStream = socket.getInputStream();
      input =
         new BufferedReader(new InputStreamReader(inStream));
      OutputStream outStream = socket.getOutputStream();
      // create a PrinterWriter object for character-mode output
      output =
         new PrintWriter(new OutputStreamWriter(outStream));
   }

   private void setLocationInfo() throws IOException
   {
	   ipaddress = socket.getInetAddress();
   }

   public void sendMessage(String message)
   		          throws IOException {
      output.println(message);
      //The ensuing flush method call is necessary for the data to
      // be written to the socket data stream before the
      // socket is closed.
      output.flush();
   } // end sendMessage

   public String receiveMessage( )
		throws IOException {
      // read a line from the data stream
      String message = input.readLine( );
      return message;
   } //end receiveMessage


	
} //end class

lynchie

First off.. if(message == "login") is wrong.. use .equals()

   MyStreamSocket myDataSocket = new MyStreamSocket
                (myConnectionSocket.accept( ));
        System.out.println("connection accepted");
        [b] message = myDataSocket.receiveMessage();[/b]
         System.out.println(message);

the message contains "login" at this point. You then create the server thread with this socket, and inside it the first thing u do is

 public void run( ) {
	      boolean done = false;
	      String message;
	      try {
	  [b]           message = myDataSocket.receiveMessage( );[/b]

which blocks and waits for another message without processing the current message.

I suggest you remove the receiveMessage() call from the EchoServer3 code and it should get past that issue.

When you do it should go past the hello..

Welcome to the Echo client.
What is the name of the server host?

What is the port number of the server host?

Connection request made
Enter login, or a single period to quit.
login
Enter your username
test
test
HELLO
hghg:
hghg: test
hghg324234: test
hghg: login failed
HELLO2
false
here
HELLO
hghg:
hghg: test
hghg324234: test