Upload Homework 2 - Goericke

assignments/src/MV3500Cohort2020JulySeptember/homework2/Goericke/GoerickeClient.java

+package MV3500Cohort2020JulySeptember.homework2.Goericke;
+
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.net.Socket;
+
+/**
+ *
+ * @author stefa
+ */
+public class GoerickeClient {
+
+    // IPv6 String constant for localhost address, similarly IPv4 127.0.0.1
+    public final static String LOCALHOST = "0:0:0:0:0:0:0:1";
+
+    public static void main(String[] args) {
+        
+        // Local vars/fields
+        Socket socket;
+        InputStream is;
+        InputStreamReader isr;
+        BufferedReader br;
+        String serverMessage;
+        
+        try {
+            while (true) {
+                System.out.println("\nGoerickeClient creating socket...");
+
+                // We request an IP to connect to ("localhost") and
+                // port number at that IP (2317). This establishes
+                // a connection to that IP in the form of a Socket
+                // object; the server uses a ServerSocket to wait for
+                // connections.
+                socket = new Socket(LOCALHOST, 2317); // locohost?
+
+                // thats my input stream 
+                is = socket.getInputStream();
+                isr = new InputStreamReader(is);
+                br = new BufferedReader(isr);
+
+                // Read a single line written by the server. We'd
+                // do things a bit differently if there were many lines to be read
+                // from the server instead of one only.
+                serverMessage = br.readLine();
+                System.out.println("The message the server sent was: '" + serverMessage + "'");
+                // socket gets closed, either automatically/silently by this code (or possibly by the server)
+                if (serverMessage.contentEquals("Welcome, how are you !!!")) {
+                    System.out.println("What a nice and friendly server");
+                } else if (serverMessage.contentEquals("Still alive there ?")){
+                    System.out.println("Yes, I am ... still .... where else should I be");
+                } else{
+                    System.out.println("Seems he does not have anything to tell");
+                }
+                
+            } // end while(true)
+        } catch (IOException e) {
+            System.err.println("Problem with TcpExample3ServerClient networking:"); // describe what is happening
+            System.err.println("Error: " + e);
+            
+            // Provide more helpful information to user if exception occurs due to running twice at one time
+            if (e instanceof java.net.BindException) {
+                System.err.println("*** Be sure to stop any other running instances of programs using this port!");
+            }
+        } finally {
+        
+            // program exit: tell somebody about that
+            System.out.println("\nclient exit");
+        }
+    }
+}

assignments/src/MV3500Cohort2020JulySeptember/homework2/Goericke/GoerickeServer.java

+package MV3500Cohort2020JulySeptember.homework2.Goericke;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.PrintStream;
+import java.net.InetAddress;
+import java.net.ServerSocket;
+import java.net.Socket;
+
+/**
+ * This runable sets up a TCP/IP server for use with a client coded 
+ * within MV3500 - Homework 2. 
+ * @author stefan goericke */
+public class GoerickeServer {
+    
+    
+    private static String getLogo(){
+        String masterString = "           #########   ######    #       #\r\n";
+        masterString = masterString + "               #       #          #     #\r\n";
+        masterString = masterString + "               #       ######      #   #\r\n";
+        masterString = masterString + "               #            #       # #\r\n";
+        masterString = masterString + "               #       ######        #\r\n\n\n";
+        return masterString;
+    }
+
+
+    /**
+     * @param args the command line arguments
+     */
+    public static void main(String[] args) {
+        System.out.print(getLogo());
+        try {
+            
+            // ServerSocket waits for a connection from a client. 
+            // Notice that it is outside the loop; ServerSocket
+            // needs to be made only once.
+            System.out.println("GoerickeServer has started... "); // it helps debugging to put this on console first
+            ServerSocket serverSocket = new ServerSocket(2317);
+            OutputStream os;
+            PrintStream ps;
+            InetAddress localAddress, remoteAddress;
+            int localPort, remotePort;
+
+            // Server is up and waiting (i.e. "blocked" or paused)
+            // Loop, infinitely, waiting for client connections.
+            // Stop the program somewhere else.
+            int counter = 0;
+            while (true) { 
+                
+                // block until connected to a client
+                try (Socket clientConnectionSocket = serverSocket.accept()) {
+                    counter++;
+                    // my output stream
+                    os = clientConnectionSocket.getOutputStream();
+                    ps = new PrintStream(os);
+                    
+                    
+                    if (counter==1){
+                        ps.println("Welcome, how are you !!!"); // this gets sent back to client!
+                    }
+                    else if (counter%10 == 0){
+                        ps.println("Still alive there ?");
+                    } else {
+                        ps.println("----------");
+                    }
+                    
+                    // Print some information locally about the Socket connection.
+                    // This includes the port and IP numbers on both sides (the socket pair).
+                     localAddress = clientConnectionSocket.getLocalAddress();
+                    remoteAddress = clientConnectionSocket.getInetAddress();
+                        localPort = clientConnectionSocket.getLocalPort();
+                       remotePort = clientConnectionSocket.getPort();
+                    
+                    if (( localAddress.getHostName().equals( localAddress.getHostAddress()) ||
+                        remoteAddress.getHostName().equals(remoteAddress.getHostAddress())) &&
+                        (counter%50==0)){
+                        System.out.println("Talking to myself ..... again");
+                    } else if (counter%50==0) {
+                        System.out.println("Connected to ....");
+                        System.out.print("(" + remoteAddress.getHostName() + "=" + remoteAddress.getHostAddress() + ", " + remotePort + " ))");
+                        System.out.println();
+                        System.out.println("I am ....");
+                        System.out.print("(" + localAddress.getHostName() + "=" +  localAddress.getHostAddress() + ", " + localPort + " ), ( ");    
+                    }
+
+                    // connection. try w/ resources explicitly ends the connection.
+                    ps.flush();
+                }
+            }
+        } catch (IOException e) {
+            System.err.println("Problem with TcpExample3Server networking: " + e);
+
+            // Provide more helpful information to user if exception occurs due to running twice at one time
+            if (e instanceof java.net.BindException) {
+                System.err.println("*** Be sure to stop any other running instances of programs using this port!");
+            }
+        }
+    }
+}