Thomerson Homework 1

deliverables/src/MV3500Cohort2018JulySeptember/homework1/ThomersonAssignment1.java

+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package MV3500Cohort2018JulySeptember.homework1;
+import java.io.*;
+import java.net.*;
+
+/**
+ * The simplest possible TCP network program. It listens for
+ * a connection, from telnet (telnet localhost 2317) or a program
+ * you write, which we will do later. Right now the TcpExample simply
+ * writes a string in response to a connection. 
+ * 
+ * Testing the running server program from telnet looks like this:
+ * 
+ * it154916:projects mcgredo$ telnet localhost 2317
+ * Trying ::1...
+ * Connected to localhost.
+ * Escape character is '^]'.
+ * This was written by the server
+ * Connection closed by foreign host.
+ * 
+ * Notice that "This was written by the server" matches 
+ * what is written by the code below, over the output stream.
+ * 
+ * After this first connection the program below drops out
+ * the bottom of the program, and does not repeat itself.
+ * The program exits.
+ * 
+/**
+ *
+ * @author courtneythomerson
+ */
+public class ThomersonAssignment1 {
+
+    public static void main(String[] args) {
+        
+        try
+        {
+            // NETBEANS IS THE SERVER.
+            // Create a new ServerSocket with the input 2317 in the constructor.
+            // SERVER SOCKET is the socket the client will connect to
+            // ServerSocket needs to be made only once
+            
+            
+            ServerSocket serverSocket = new ServerSocket(2317);
+            
+            //**Set a time out to stop the .accept method from blocking indefinitely
+            //serverSocket.setSoTimeout(10000);
+            
+            //**Add a second server socket to listen for clients
+            //ServerSocket secondServerSocket = new ServerSocket(1990);
+            //secondServerSocket.setSoTimeout(1);
+            
+            //Count how many connections have been made
+            int connectionCount = 0;
+            
+            while(true){
+                // The Socket object represents the connection between
+                // the server and client, including a full duplex
+                // connection (.accept() is a blocking method)
+                Socket clientConnection = serverSocket.accept();
+              
+                //Once a client has been excepted iterate the connectionCount
+                connectionCount += 1;
+                
+                // Use Java io classes to write text (as opposed to
+                // unknown bytes of some sort) to the client
+                OutputStream os = clientConnection.getOutputStream();
+                PrintStream ps = new PrintStream(os);
+            
+                //Confirm the connection on both sides through NetBeans
+                ps.println("This is the server (NetBeans) writting to the client (Terminal)"); // to remote client
+                System.out.println("This is the server (NetBeans) confirming the connection with the client (Terminal)"); // to server console
+            
+                //NetBeans tells the client which connection number they are
+                ps.println("This connection was number " + connectionCount );
+                
+                //Get information about the connection
+                //SERVER IP Address
+                InetAddress localAddress = clientConnection.getLocalAddress();
+                //SERVER Port
+                int localPort = clientConnection.getLocalPort();
+                
+                //CLIENT IP Address
+                InetAddress remoteAddress = clientConnection.getInetAddress();
+                //CLIENT Port
+                int remotePort = clientConnection.getPort();
+                
+                //Have the server (NetBeans) show all the collected information
+                System.out.println("\nSocket Pair:\n\t"
+                        + "Server: IP - " + localAddress.toString() +  ", Port - " + localPort + "\n\t" 
+                        + "Client: IP - " + remoteAddress.toString() + ", Port - " + remotePort);
+                
+                System.out.println("\nConnection: " + connectionCount + "\n");
+                
+                // "flush()" in important in that it forces a write 
+                // across what is in fact a slow connection
+                ps.flush();
+            
+                clientConnection.close();
+            }
+        }
+        catch(Exception e)
+        {
+            System.out.println("problem with networking: " + e);
+        }
+    }
+    
+}