client.java

HTTP/1.0 Client HTTP/1.0 Server

/**
 * @date 2009/4/6
 * @author ***
 * @version 1.0.0
 * 
 * TODO To change the template for this generated type comment go to
 * Window - Preferences - Java - Code Style - Code Templates
 */
import java.io.*;
import java.net.*;

public class Client {
	/**
	 * Main function of the class Client.
	 * 
	 * @param args
	 *            the first parameter is hostname of the server.
	 * @throws Exception
	 */
	public static void main(String[] args) throws IOException {
		// Creat a socket
		Socket clientSocket = null;
		// Open a TCP connection to port 80 of the server.
		try {
			clientSocket = new Socket(args[0], 80);
		} catch (IOException e) {
			System.out.println(e);
		}
		System.out.println("Hello," + args[0] + "is connecting.");
		// inFromUser is used to receive the users' input
		BufferedReader inFromUser = new BufferedReader(new InputStreamReader(
				System.in));
		// inFromServer is used to get information from server
		BufferedReader inFromServer = new BufferedReader(new InputStreamReader(
				clientSocket.getInputStream()));
		// Receive the server's response, show the user the response headers,
		getResponse(inFromUser, inFromServer, clientSocket);
		// Save the response contents to a file.
		saveResponse(inFromServer);
		// close the inFromServer and the inFromUser
		inFromServer.close();
		inFromUser.close();
	}

	/**
	 * Receive the server's response, show the user the response headers,
	 * 
	 * @param request
	 *            the request specified by users.
	 * @throws IOException
	 */
	public static void getResponse(BufferedReader inFromUser,
			BufferedReader inFromServer, Socket clientSocket)
			throws IOException {
		try {
			PrintWriter outToServer = new PrintWriter(clientSocket
					.getOutputStream());
			// get user's and send it to server
			String request = "";
			System.out
					.println("\rPlease enter your request as 'GET / HTTP/1.0':");
			request = inFromUser.readLine() + "\r\n";
			outToServer.println(request);
			outToServer.flush();
			// print the header of the information from server
			System.out.println("Header:");
			// read the first line from server
			String sentence = inFromServer.readLine();
			while (sentence.length() != 0) {
				System.out.println(sentence);
				sentence = inFromServer.readLine();
			}
		} catch (IOException e) {
			System.out.println(e);
		}
	}

	/**
	 * Save the response contents to a file.
	 * 
	 * @param request
	 *            the file's name.
	 * @throws IOException
	 */
	public static void saveResponse(BufferedReader inFromServer)
			throws IOException {
		try {
			// input the file'name
			System.out.println("\rPlease enter a file's name: ");
			BufferedReader input = new BufferedReader(new InputStreamReader(
					System.in));
			String fileName = input.readLine();
			PrintWriter file = new PrintWriter(new FileWriter(fileName));
			String sentence = "";
			// Write the response contents to the file
			sentence = inFromServer.readLine();
			while (sentence != null) {
				file.println(sentence);
				sentence = inFromServer.readLine();
			}
			// close the file
			file.close();
			System.out.println("\rThe content is saved in " + fileName + "");
		} catch (IOException e) {
			System.out.println(e);
		}
	}
}