example simulation program for students

examples/src/OpenDis7Examples/ExampleSimulation.java

+/**
+ * Copyright (c) 2008-2020, MOVES Institute, Naval Postgraduate School (NPS). All rights reserved.
+ * This work is provided under a BSD open-source license, see project license.html and license.txt
+ */
+package OpenDis7Examples;
+
+import edu.nps.moves.dis7.enumerations.VariableRecordType;
+import edu.nps.moves.dis7.pdus.CommentPdu;
+import edu.nps.moves.dis7.pdus.EntityID;
+import edu.nps.moves.dis7.pdus.EntityStatePdu;
+import edu.nps.moves.dis7.pdus.FirePdu;
+import edu.nps.moves.dis7.pdus.Pdu;
+import edu.nps.moves.dis7.utilities.DisThreadedNetworkInterface;
+import edu.nps.moves.dis7.utilities.PduFactory;
+
+public class ExampleSimulation
+{
+    // class variables
+    PduFactory pduFactory = new PduFactory();
+    DisThreadedNetworkInterface disNetworkInterface;
+    DisThreadedNetworkInterface.PduListener pduListener;
+    Pdu receivedPdu;
+    
+    String networkAddress = "239.1.2.3";
+    int    networkPort    = 3000;
+
+    /**
+     * Initialize network interface, choosing best available network interface
+     */
+    public void setUpNetworkInterface()
+    {
+        disNetworkInterface = new DisThreadedNetworkInterface(networkAddress, networkPort);
+        
+        System.out.println("Network confirmation: address=" + disNetworkInterface.getMcastGroup() + " port=" + disNetworkInterface.getDisPort());
+        pduListener = new DisThreadedNetworkInterface.PduListener()
+        {
+            /** Callback handler for listener */
+            @Override
+            public void incomingPdu(Pdu newPdu)
+            {
+                receivedPdu = newPdu;
+            }
+        };
+        disNetworkInterface.addListener(pduListener);
+    }
+
+    /** All done, release network resources */
+    public void tearDownNetworkInterface()
+    {
+        disNetworkInterface.removeListener(pduListener);
+        disNetworkInterface.kill();
+        disNetworkInterface = null;
+    }
+
+    /** 
+     * Send a PDU of any type
+     * @param pdu the pdu to send
+     */
+    private void sendPdu(Pdu pdu)
+    {
+        try
+        {
+            disNetworkInterface.send(pdu);
+            Thread.sleep(100); // TODO consider refactoring the wait logic and moving externally
+        } 
+        catch (InterruptedException ex)
+        {
+            System.err.println(this.getClass().getName() + " Error sending PDU: " + ex.getLocalizedMessage());
+            System.exit(1);
+        }
+    }
+
+    /**
+     * PDU sending: Entity State, Fire, Comment
+     * @see <a href="https://docs.oracle.com/javase/tutorial/java/javaOO/arguments.html">Passing Information to a Method or a Constructor</a> Arbitrary Number of Arguments
+     * @param entityStatePdu the ESPDU to send, if any
+     * @param firePdu        the FirePDU to send, if any
+     * @param commentType    enumeration value describing the narrative comment
+     * @param comments       String array of narrative comments
+     */
+    public void createSendPdus(EntityStatePdu entityStatePdu,
+                               FirePdu firePdu,
+                               VariableRecordType commentType,
+                               // vararg... variable length string
+                               String... comments)
+    {
+        if (entityStatePdu != null)
+            sendPdu(entityStatePdu);
+            
+        if (firePdu != null)
+            sendPdu(firePdu); // bang
+        
+        if ((comments == null) || (comments.length > 0))
+        {
+            if (commentType == null)
+                commentType = VariableRecordType.OTHER;
+            CommentPdu commentPdu = pduFactory.makeCommentPdu(commentType, comments);
+            sendPdu(commentPdu);
+        }
+    }
+  
+    public static void main(String[] args)
+    {
+        // initial execution: can handle args array of initialization arguments here
+        
+        ExampleSimulation thisProgram = new ExampleSimulation(); // creates instance
+
+        thisProgram.setUpNetworkInterface();
+
+        thisProgram.runSimulation ();
+
+        thisProgram.tearDownNetworkInterface();
+    }
+    
+    public void runSimulation ()
+    {
+        final int MAX_LOOP_COUNT = 10;
+        int loopCount = 0;
+        VariableRecordType narrativeType = VariableRecordType.OTHER;
+        boolean simulationComplete = false; // termination condition
+        
+        // model setup
+        EntityID       entityID_1    = new EntityID();
+        entityID_1.setSiteID(1).setApplicationID(2).setEntityID(3);
+
+        EntityStatePdu entityStatePdu = pduFactory.makeEntityStatePdu();
+        entityStatePdu.setEntityID(entityID_1);
+
+        FirePdu               firePdu = pduFactory.makeFirePdu();
+        
+        while (loopCount < MAX_LOOP_COUNT) // loop while allowed, can set additional conditions to break
+        {
+            String narrativeMessage1, narrativeMessage2, narrativeMessage3;
+            // initialize loop variables
+            loopCount++;
+            
+            // your simulation code here!
+            
+            
+            
+            
+            // your narrative code for CommentPdu here
+            narrativeMessage1 = "MV3500 ExampleSimulation";
+            narrativeMessage2 = "runSimulation loop " + loopCount;
+            narrativeMessage3 = ""; // intentionally blank for testing
+            
+            // your termination condition
+            if (loopCount > 4) // for example
+            {
+                simulationComplete = true;
+                System.out.println ("*** termination condition met, simulationComplete=" + simulationComplete);
+            }
+            
+            // loop now finished so terminate if simulation complete, otherwise send latest PDUs and continue
+            if (simulationComplete)
+                break;
+            System.out.println ("sending PDUs for simulation step " + loopCount + ", monitor loopback to confirm sent");
+            createSendPdus(entityStatePdu, firePdu, null, narrativeMessage1, narrativeMessage2, narrativeMessage3);
+            System.out.println ("... PDUs successfully sent");
+        }
+    }
+}