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A Test Client

A simple HTTP client in Java.

Read command-line arguments: 
import java.net.*;
import java.io.*;
import java.util.*;

public class MultiClient
{
    public static void main(String[] args) 
    {
        // read arguments
        if (args.length!=2) {
            System.out.println("Usage: java MultiClient <host> <port>");
            System.exit(-1);
        }
        String host = args[0];
        int port = Integer.parseInt(args[1]);

        System.out.println("MultiClient 1.0");
        System.out.println("Enter request followed by one empty line or 'quit' to quit.");
        BufferedReader user = new BufferedReader(new InputStreamReader(System.in));

        try {

Read user's request and send it to the server: 
              
        mainloop:
            while (true) {
                // read user request
                StringBuffer req = new StringBuffer();
                boolean done = false, first = true;
                while (!done) {
                    // get a line
                    System.out.print(host + ":" + port + "> ");
                    String line = user.readLine();
                    if (line.equals("quit"))
                        break mainloop;
                    req.append(line).append("\r\n");
                    if (line.length()==0 && !first)
                        done = true; // done when reading blank line
                    first = false;
                }

Make connection to server and send the request: 
              
                Socket socket = null; 
                try {
                    // create socket and connect (don't occupy port too long)
                    socket = new Socket(host, port); 
                    socket.setSoTimeout(60000); // set timeout to 1 minute
                    PrintStream out = new PrintStream(socket.getOutputStream());
                    out.print(req); // send bytes in default encoding
                    out.flush();

Get server reply and print it to standard out: 
                              
                    // show reply
                    BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                    while (true) {
                        String line = in.readLine();
                        if (line==null)
                            break;
                        System.out.println(line);
                    }

Close connection and catch exceptions: 
              
                } catch (Exception e) { System.err.println(e); }
                if (socket!=null)                   
                    socket.close(); // close connection
            }
        }
        catch (Exception e) { System.err.println(e); }
    }
}

- a good starting point for making a simple Web browser - "just" add an HTML parser and a GUI (as Notscape using javax.swing.text.html)...

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