Question

Project Description

In this project, you will be developing a multithreaded Web server and a simple web client. The Web server and Web client communicate using a text-based protocol called HTTP (Hypertext Transfer Protocol).

Requirements for the Web server

• The server is able to handle multiple requests concurrently. This means the implementation is multithreaded. In the main thread, the server listens to a specified port, e.g., 8080. Upon receiving an HTTP request, the server sets up a TCP connection to the requesting client and serves the request in a separate thread. After sending the response back to the client, it closes the connection.
• The server is assumed to work with HTTP GET messages. If the requested file exists, the server responds with “HTTP/1.1 200 OK” together with the requested page to the client, otherwise it sends a corresponding error message, e.g., “HTTP/1.1 404 Not Found” or “HTTP/1.1 400 Bad Request”.
• If running the server program using command line, the syntax should be:

server_code_name [<port_number>]

where the optional <port_number> is the port on which the server is listening to connections from clients. If the port number is not entered, the default port 8080 is used.

• You can test your Web server implementation on your local machine using a Web browser, e.g., Internet Explorer, Firefox, or Chrome. You need to specify the used port number within the URL, for example,

http://localhost:8080/index.htm

If omitting the port number portion, i.e., 8080, the browser will use the default port 80.

• The server should response with a default page when users do not enter a specific page in the URL, for example,

http://localhost:8080/

It should also work when the request includes a path to the requested file, for example,

http://localhost:8080/path/to/file/example.htm

• You should display/log the request and header lines of request messages on the server for the purpose of debugging.

Requirements for the simple Web client

• The client is able to connect to the server via a socket and to request a page on the server.
• Upon receipt of the response message from the server, the client extracts and displays/logs the message status, and then retrieves the page content from the message body.

• If running the client program using command line, the syntax should be:

client_code_name <server_IPaddress/name> [<port_number>] [<requested_file_name>]

where the <server_IPaddress/name> is the IP address or name of the Web server, e.g., 127.0.0.1 or localhost for the server running on the local machine. The optional <port_number> is the port on which the server is listening to connections from clients. If the port number is not entered, the default port 8080 is used. The optional <requested_file_name> is the name of the requested file, which may include the path to the file. If the file name is not entered, the default file “index.htm” is used.

I Just need help with the simple web client

Use Java

I used the eclipse IDE to develop the web server.

Answer 1

mport java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;


public class Server_X_Client {
public static void main(String args[]){


    Socket s=null;
    ServerSocket ss2=null;
    System.out.println("Server Listening......");
    try{
        ss2 = new ServerSocket(4445); // can also use static final PORT_NUM , when defined

    }
    catch(IOException e){
    e.printStackTrace();
    System.out.println("Server error");

    }

    while(true){
        try{
            s= ss2.accept();
            System.out.println("connection Established");
            ServerThread st=new ServerThread(s);
            st.start();

        }

    catch(Exception e){
        e.printStackTrace();
        System.out.println("Connection Error");

    }
    }

}

}

class ServerThread extends Thread{  

    String line=null;
    BufferedReader  is = null;
    PrintWriter os=null;
    Socket s=null;

    public ServerThread(Socket s){
        this.s=s;
    }

    public void run() {
    try{
        is= new BufferedReader(new InputStreamReader(s.getInputStream()));
        os=new PrintWriter(s.getOutputStream());

    }catch(IOException e){
        System.out.println("IO error in server thread");
    }

    try {
        line=is.readLine();
        while(line.compareTo("QUIT")!=0){

            os.println(line);
            os.flush();
            System.out.println("Response to Client  :  "+line);
            line=is.readLine();
        }   
    } catch (IOException e) {

        line=this.getName(); //reused String line for getting thread name
        System.out.println("IO Error/ Client "+line+" terminated abruptly");
    }
    catch(NullPointerException e){
        line=this.getName(); //reused String line for getting thread name
        System.out.println("Client "+line+" Closed");
    }

    finally{    
    try{
        System.out.println("Connection Closing..");
        if (is!=null){
            is.close(); 
            System.out.println(" Socket Input Stream Closed");
        }

        if(os!=null){
            os.close();
            System.out.println("Socket Out Closed");
        }
        if (s!=null){
        s.close();
        System.out.println("Socket Closed");
        }

        }
    catch(IOException ie){
        System.out.println("Socket Close Error");
    }
    }//end finally
    }

// Client

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.Socket;

public class NetworkClient {

public static void main(String args[]) throws IOException{


    InetAddress address=InetAddress.getLocalHost();
    Socket s1=null;
    String line=null;
    BufferedReader br=null;
    BufferedReader is=null;
    PrintWriter os=null;

    try {
        s1=new Socket(address, 4445); // You can use static final constant PORT_NUM
        br= new BufferedReader(new InputStreamReader(System.in));
        is=new BufferedReader(new InputStreamReader(s1.getInputStream()));
        os= new PrintWriter(s1.getOutputStream());
    }
    catch (IOException e){
        e.printStackTrace();
        System.err.print("IO Exception");
    }

    System.out.println("Client Address : "+address);
    System.out.println("Enter Data to echo Server ( Enter QUIT to end):");

    String response=null;
    try{
        line=br.readLine(); 
        while(line.compareTo("QUIT")!=0){
                os.println(line);
                os.flush();
                response=is.readLine();
                System.out.println("Server Response : "+response);
                line=br.readLine();

            }



    }
    catch(IOException e){
        e.printStackTrace();
    System.out.println("Socket read Error");
    }
    finally{

        is.close();os.close();br.close();s1.close();
                System.out.println("Connection Closed");

    }

}
}