can't connect to remote host

[Sid]

hello!

I have a client/server program in which client lets user input two
numbers and the server adds the numbers and returns the sum to client.

the problems I am having are:

1. client is not able to connect to remote server. it is only
connecting to local host.

2. if a string seperated by "non-numeric" characters (e.g. 34a2dd) is
sent, both client and server throw an uncaught exception. i need to
fix the client or server or both and give useful feedback to the user.
i need to do the error checking of user i/p so that user enters only
integers seperated by whitespace.

I am attaching my code.
I am new to java and probably don't know much.
'shall greatly appreciate your help.

thanks in advance,
siddharth

code:

// usage: java TCPAdditionServer3 <port number>
// default port is 7777
// connection to be closed by client
// this server handles only one connection

import java.io.*;
import java.net.*;
import java.lang.*;
import java.util.*;

class TCPAdditionServer3{
public static void main(String[] args)throws Exception{
String clientSentence,capitalizedSentence;
int sum=0;
String sumString = "";
InetAddress serverAddress;
int portNumber = 7777;
Socket connectionSocket = null;

try {
portNumber = Integer.parseInt(args[0]);
}
catch (Exception e) {
System.out.println(" port = 7777 (default)");
portNumber = 7777;
}

// create welcoming socket at port number specified by user or
7777 if no choice is specified by user
ServerSocket welcomeSocket=new ServerSocket(portNumber);

//server infinite loop
while(true){
try {
// wait, on welcoming socket for contact by
client
connectionSocket=welcomeSocket.accept();
} catch (IOException e) {
System.out.println("Accept failed:");
System.exit(-1);
}

// create input stream, attached to socket
BufferedReader inFromClient=new BufferedReader(new
InputStreamReader(connectionSocket.getInputStream()));
// create output stream, attached to socket
DataOutputStream outToClient=new
DataOutputStream(connectionSocket.getOutputStream());

// read in line from socket
clientSentence=inFromClient.readLine();

StringTokenizer st= new StringTokenizer(clientSentence);
while(st.hasMoreTokens()) {
sum += Integer.parseInt(st.nextToken());
}

System.out.println("Waiting for connections on port " +
connectionSocket.getLocalPort() + " ... ");
System.out.println("Received connection from " +
connectionSocket.getInetAddress() + ":" +
connectionSocket.getLocalPort());

sumString = Integer.toString(sum);
clientSentence = " ";
capitalizedSentence = clientSentence + sumString + "\n";

//write out line to socket
outToClient.writeBytes(capitalizedSentence);

//connection closed by client
try {
connectionSocket.close();
System.out.println("Connection closed by client");
}
catch (IOException e) {
System.out.println(e);
}

}
}

}

code:

// usage: java TCPAdditionClient3 <server> <port>
// default port is 7777

/**
* TCPAdditionClient1.java
*
* @author Siddharth Jain
* @version 3.0
*/

/** Client Code */

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

/** this is the main class */
class TCPAdditionClient3{
public static void main(String[] args)throws Exception{

String sentence,sentc,portNumberString;
int portNumber= 7777;
String hostName = "localhost";
String modifiedSentence;
InetAddress clientAddress;
/** create input stream */
BufferedReader inFromUser1=new BufferedReader(new
InputStreamReader(System.in));

/** read arguments */
if(args.length == 2) {
hostName = args[0];
try {
portNumber = Integer.parseInt(args[1]);
System.out.println("client user i/p port number " +
portNumber);
}
catch (Exception e) {
System.out.println(" server port = 7777 (default)");
portNumber = 7777;
}
}

/** connect to server */
try{
/** create client socket, connect to server */
Socket clientSocket=new Socket(hostName,portNumber);

if (clientSocket.isConnected()== true);
{
System.out.println("Connecting to Server " +
clientSocket.getInetAddress() + ":" + clientSocket.getPort() + "..." +
"Connected");
}

/** create output stream attached to socket */
DataOutputStream outToServer=new
DataOutputStream(clientSocket.getOutputStream());
/** create input stream attached to socket */
BufferedReader inFromServer=new BufferedReader(new
InputStreamReader(clientSocket.getInputStream()));

System.out.println();
System.out.println("Enter a string of integers seperated by
non-numeric characters:");

sentence = inFromUser1.readLine();
/**send line to server */
outToServer.writeBytes(sentence+"\n");
/** read line from server */
modifiedSentence=inFromServer.readLine();
System.out.println("From Server-----> The Sum
is:"+modifiedSentence);

try {
clientSocket.close();
}
catch(IOException e) {
System.out.println(e);
}

} catch(UnknownHostException e) {
System.err.println(" Don't know about host: ");
System.exit(1);
} catch(IOException e) {
System.err.println(" Couldn't get I/O for the connection");
System.exit(1);
}

}
}

 

[Andrew Thompson]

I have a client/server program in which client lets user input two
numbers and the server adds the numbers and returns the sum to client.

the problems I am having are:

You are having some problems even before your code, let's
get those sorted first.

1. client is not able to connect to remote server.

Fails how? What happens, are exceptions thrown, what exceptions?

....it is only connecting to local host.

Also, ask a specific question.
<http://www.physci.org/codes/javafaq.jsp#specific>
(One of the aspects of asking a smart question is not to
forget to *ask* an actual question)

....

I am attaching my code.

Tips for example..
Indent code lines with spaces, it is easier to read
(but still keep them short). Further tips on the example.

I am new to java and probably don't know much.
'shall greatly appreciate your help.

You are posting to the wrong group.
The best group for those starting Java can be found here..
<http://www.physci.org/codes/javafaq.jsp#cljh>

See to those matters in a new post to c.l.j.help
(and I suggest you deal with them in separate threads)
and you will probably get more and better help.

HTH