Server

gistfile1.java

package com.skalar;

import 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 {
	public Server(int port) {
		calculator = new PostfixCalculator();
		
		in = null;
	    out = null;
	    
	    try {
		    serverSocket = new ServerSocket(port);
		} catch (IOException e) {
		    System.out.println("Could not listen on port: " + port);
		    return;
		}
	}
	
	public void startServer() {
		try {
			System.out.print("Waiting for a client...");
			fromClient = serverSocket.accept();
			System.out.println("Client connected");
		} catch (IOException e) {
			System.out.println("Can't accept");
			return;
		}
		
		try {
			in = new BufferedReader(new InputStreamReader(
					fromClient.getInputStream()));
			out = new PrintWriter(fromClient.getOutputStream(), true);
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		String input;

		try {
			System.out.println("Wait for messages");
			while ((input = in.readLine()) != null) {
				if (input.equalsIgnoreCase("exit"))
					break;
				out.println(calculator.calculateFromInfix(input));
				System.out.println(input);
			}
			out.close();
			in.close();
			fromClient.close();
			serverSocket.close();
		} catch (IOException exc) {
			exc.printStackTrace();
		}
	}
	
	public static void main(String[] args) {
		Server server = new Server(3000);
		server.startServer();
	}
	
	private PostfixCalculator calculator;
	
	private BufferedReader in;
	private PrintWriter out;
	
	private ServerSocket serverSocket;
	private Socket fromClient;
}