refactor rename project 2 files to match folder (and Java) naming conventions

projects/Assignments/homework2/Hanley_README_MulticastHW.txt

+Hanley README for Multicast Homework
+
+Modified the code from multicast example 1.
+
+- adjusted packet to get compiled for every send
+- computed the "position" of the entity for each packet
+- shout out to Chris A for identifying the need to change the receiver to listen for doubles and not floats
+
+
+********** System outputs for classes:
+
+Sender:
+run-single:
+/239.1.2.15
+Sent multicast packet 0 of 100
+Sent multicast packet 1 of 100
+Sent multicast packet 2 of 100
+Sent multicast packet 3 of 100
+Sent multicast packet 4 of 100
+Sent multicast packet 5 of 100
+Sent multicast packet 6 of 100
+Sent multicast packet 7 of 100
+
+
+Receiver:
+run-single:
+/239.1.2.15
+Number received: 1 X Pos: 1.4142135623730951 Y Pos: 3.414213562373095
+Number received: 2 X Pos: 2.8284271247461903 Y Pos: 4.82842712474619
+Number received: 3 X Pos: 4.242640687119286 Y Pos: 6.242640687119285
+Number received: 4 X Pos: 5.656854249492381 Y Pos: 7.65685424949238
+Number received: 5 X Pos: 7.0710678118654755 Y Pos: 9.071067811865476
+Number received: 6 X Pos: 8.485281374238571 Y Pos: 10.485281374238571
+Number received: 7 X Pos: 9.899494936611667 Y Pos: 11.899494936611667
+Number received: 8 X Pos: 11.313708498984763 Y Pos: 13.313708498984763
\ No newline at end of file

projects/Assignments/homework2/Hanley_multicastHW_receiver.java

+/**
+ * This assignment uses the code from MV3500 example "multicastExample1"  
+ * modifications were made to way the packet is read to facilitate the double  
+ * instead of the float.
+ * 
+ * @author Brian
+ */
+import java.io.*;
+import java.net.*;
+
+
+public class Hanley_multicastHW_receiver {
+    public static final String MULTICAST_ADDRESS = "239.1.2.15";
+    public static final int DESTINATION_PORT = 1717;
+    /** How many routers can be crossed */
+    public static final int TTL = 10; 
+    
+    public static void main(String[] args) 
+    {
+        try
+        {
+        
+            // This is a java/IPv6 problem. You should also add it to the
+            // arguments used to start the app, eg -Djava.net.preferIPv4Stack=true
+            // set in the "run" section of preferences. Also, typically
+            // netbeans must be restarted after these settings.
+            // https://stackoverflow.com/questions/18747134/getting-cant-assign-requested-address-java-net-socketexception-using-ehcache
+            System.setProperty("java.net.preferIPv4Stack", "true");
+            
+            
+            MulticastSocket multicastSocket = new MulticastSocket(DESTINATION_PORT);
+            multicastSocket.setTimeToLive(TTL);
+            InetAddress multicastAddress = InetAddress.getByName(MULTICAST_ADDRESS);
+            System.out.println(multicastAddress);            
+            // Join group useful on receiving side
+            multicastSocket.joinGroup(multicastAddress);
+            // You can join multiple groups here
+            
+            int count = 0;
+            
+            while(true)
+            {
+                byte[] packetArray = new byte[1500];
+                DatagramPacket packet = new DatagramPacket(packetArray, packetArray.length);
+                
+                multicastSocket.receive(packet);
+                count++;
+                
+                ByteArrayInputStream bais = new ByteArrayInputStream(packet.getData());
+                DataInputStream dis = new DataInputStream(bais);
+                double firstNumber = dis.readDouble();
+                double secondNumber = dis.readDouble();
+                
+                System.out.println("Number received: " + count + " X Pos: " + firstNumber + " Y Pos: " + secondNumber);
+            }
+        }
+        catch(Exception e)
+        {
+            System.out.println(e);
+        }
+    }
+    
+}

projects/Assignments/homework2/Hanley_multicastHW_sender.java

+/**
+ * This assignment uses the code from MV3500 example "multicastExample1"  
+ * modifications were made to the packet creation and where the packet is 
+ * assembled.
+ * 
+ * @author Brian
+ */
+
+
+import java.io.*;
+import java.net.*;
+
+
+public class Hanley_multicastHW_sender {
+    public static final String MULTICAST_ADDRESS = "239.1.2.15";
+    public static final int DESTINATION_PORT = 1717;
+    /** How many routers can be crossed */
+    public static final int TTL = 10;
+    private int velocity;
+    private float xPos;
+    private float yPos;
+    
+    
+    public static void main(String[] args) 
+    {
+        int velocity = 2;
+        int dir = 45;
+        double xPos = 0;
+        double yPos = 2;
+              
+        
+        try
+        {
+            // This is a java/IPv6 problem. You should also add it to the
+            // arguments used to start the app, eg -Djava.net.preferIPv4Stack=true
+            // set in the "run" section of preferences. Also, typically
+            // netbeans must be restarted after these settings.
+            // https://stackoverflow.com/questions/18747134/getting-cant-assign-requested-address-java-net-socketexception-using-ehcache
+            System.setProperty("java.net.preferIPv4Stack", "true");
+            
+            
+            MulticastSocket multicastSocket = new MulticastSocket(1718);
+            multicastSocket.setTimeToLive(TTL);
+            InetAddress multicastAddress = InetAddress.getByName(MULTICAST_ADDRESS);
+            System.out.println(multicastAddress);            
+            // Join group useful on receiving side
+            multicastSocket.joinGroup(multicastAddress);
+            // You can join multiple groups here
+            
+       
+            // How fast does this go? Does UDP try to slow it down, or does
+            // this cause network problems? (hint: yes for an unlimited send
+            // rate, unlike TCP). How do you know on the receiving side
+            // that you haven't received a duplicate UDP packet, out of
+            // order packet, or dropped packet?
+            
+            for(int idx = 0; idx < 100; idx++)
+            {
+                
+                xPos = xPos + (Math.cos(Math.toRadians(dir))*velocity); //computes the horixontal displacement for each movement based on velocity - this is a fixed velocity and time increment
+                yPos = yPos + (Math.sin(Math.toRadians(dir))*velocity); //computes the vertical displacement for each movement based on velocity - this is a fixed velocity and time increment
+                
+                ByteArrayOutputStream baos = new ByteArrayOutputStream();
+                DataOutputStream dos = new DataOutputStream(baos);
+                dos.writeDouble(xPos);
+                dos.writeDouble(yPos);
+                
+                
+                byte[] buffer = baos.toByteArray();
+                
+                DatagramPacket packet = new DatagramPacket(buffer, buffer.length, multicastAddress, DESTINATION_PORT);
+                
+               multicastSocket.send(packet);
+               baos.reset();
+               Thread.sleep(1000); // Send 100, one per second
+               System.out.println("Sent multicast packet " + idx + " of 100");
+            }
+        }
+        catch(Exception e)
+        {
+            System.out.println(e);
+        }
+    }
+    
+}