Implemented server re-registration when a server closes / updates

- When a server is closed, it will disappear from the server list
- When a player joins a server, the number of spaces left will decrease
- Servers now disappear instead of duplicating
- Added tests for ServerDescription
- Added documentation for new classes

Tags: #story[1247]

src/main/java/seng302/gameServer/GameState.java

@@ -1,37 +1,22 @@
 package seng302.gameServer;
 
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
 import javafx.scene.paint.Color;
-import javax.xml.parsers.DocumentBuilder;
-import javax.xml.parsers.DocumentBuilderFactory;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.w3c.dom.Document;
 import org.xml.sax.InputSource;
-import seng302.gameServer.messages.BoatAction;
-import seng302.gameServer.messages.BoatStatus;
-import seng302.gameServer.messages.CustomizeRequestType;
-import seng302.gameServer.messages.MarkRoundingMessage;
-import seng302.gameServer.messages.MarkType;
-import seng302.gameServer.messages.Message;
-import seng302.gameServer.messages.RoundingBoatStatus;
-import seng302.gameServer.messages.YachtEventCodeMessage;
-import seng302.model.GeoPoint;
-import seng302.model.Limit;
-import seng302.model.Player;
-import seng302.model.PolarTable;
-import seng302.model.ServerYacht;
+import seng302.gameServer.messages.*;
+import seng302.model.*;
 import seng302.model.mark.CompoundMark;
 import seng302.model.mark.Mark;
 import seng302.model.mark.MarkOrder;
 import seng302.utilities.GeoUtility;
 import seng302.utilities.XMLParser;
 
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import java.util.*;
+
 /**
  * A Static class to hold information about the current state of the game (model)
  * Also contains logic for updating itself on regular time intervals on its own thread
@@ -699,4 +684,11 @@ public class GameState implements Runnable {
     public static void resetCustomizationFlag() {
         customizationFlag = false;
     }
+
+    public static Integer getSpacesLeft(){
+        Integer numberOfPlayers = GameState.getPlayers().size();
+        Integer maxPlayers = GameState.MAX_PLAYERS;
+
+        return maxPlayers - numberOfPlayers - 1;
+    }
 }

src/main/java/seng302/gameServer/MainServerThread.java

@@ -1,17 +1,26 @@
 package seng302.gameServer;
 
-import javafx.application.Platform;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.w3c.dom.Document;
+import org.xml.sax.InputSource;
+import org.xml.sax.SAXException;
 import seng302.gameServer.messages.*;
 import seng302.model.GeoPoint;
 import seng302.model.Player;
 import seng302.model.PolarTable;
 import seng302.model.ServerYacht;
 import seng302.model.mark.CompoundMark;
+import seng302.model.stream.xml.parser.RegattaXMLData;
 import seng302.utilities.GeoUtility;
+import seng302.utilities.XMLGenerator;
+import seng302.utilities.XMLParser;
 
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import javax.xml.parsers.ParserConfigurationException;
 import java.io.IOException;
+import java.io.StringReader;
 import java.net.ServerSocket;
 import java.time.LocalDateTime;
 import java.util.*;
@@ -42,6 +51,41 @@ public class MainServerThread implements Runnable, ClientConnectionDelegate {
     private ArrayList<ServerToClientThread> serverToClientThreads = new ArrayList<>();
     private Logger logger = LoggerFactory.getLogger(MainServerThread.class);
 
+    private void startAdvertisingServer(){
+        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
+        DocumentBuilder db;
+        Document doc;
+        XMLGenerator generator = new XMLGenerator();
+
+        try {
+            db = dbf.newDocumentBuilder();
+            String regatta = generator.getRegattaAsXml();
+            StringReader stringReader = new StringReader(regatta);
+            InputSource is = new InputSource(stringReader);
+            doc = db.parse(is);
+        } catch (ParserConfigurationException | IOException | SAXException e) {
+            logger.warn("Couldn't load race regatta");
+            return;
+        }
+
+        RegattaXMLData regattaXMLData = XMLParser.parseRegatta(doc);
+
+        Integer spacesLeft = GameState.getSpacesLeft();
+
+        // No spaces left on server
+        if (spacesLeft < 1){
+            return;
+        }
+
+        // Start advertising server
+        try{
+            ServerAdvertiser.getInstance().setMapName(regattaXMLData.getCourseName()).setSpacesLeft(spacesLeft);
+            ServerAdvertiser.getInstance().registerGame(PORT, regattaXMLData.getRegattaName());
+        } catch (IOException e) {
+            logger.warn("Could not register server");
+        }
+    }
+
     public MainServerThread() {
         new GameState("localhost");
         try {
@@ -50,13 +94,7 @@ public class MainServerThread implements Runnable, ClientConnectionDelegate {
             serverLog("IO error in server thread handler upon trying to make new server socket", 0);
         }
 
-        // Start advertising server
-        try{
-            ServerAdvertiser.getInstance().registerGame(PORT, "PP Test Server", 10, "Random Map");
-        } catch (IOException e) {
-            logger.warn("Could not register server");
-        }
-
+        startAdvertisingServer();
 
         PolarTable.parsePolarFile(getClass().getResourceAsStream("/config/acc_polars.csv"));
         GameState.addMarkPassListener(this::broadcastMessage);
@@ -189,6 +227,12 @@ public class MainServerThread implements Runnable, ClientConnectionDelegate {
             }
         });
         serverToClientThread.addDisconnectListener(this::clientDisconnected);
+
+        try {
+            ServerAdvertiser.getInstance().setSpacesLeft(GameState.getSpacesLeft());
+        } catch (IOException e) {
+            logger.warn("Couldn't update advertisement");
+        }
     }
 
     /**
@@ -215,6 +259,13 @@ public class MainServerThread implements Runnable, ClientConnectionDelegate {
             }
         }
         serverToClientThreads.remove(closedConnection);
+
+        try {
+            ServerAdvertiser.getInstance().setSpacesLeft(GameState.getSpacesLeft());
+        } catch (IOException e) {
+            logger.warn("Couldn't update advertisement");
+        }
+
         closedConnection.terminate();
     }
 
@@ -222,7 +273,7 @@ public class MainServerThread implements Runnable, ClientConnectionDelegate {
         try {
             ServerAdvertiser.getInstance().unregister();
         } catch (IOException e) {
-            logger.warn("Error unregistering server");
+            logger.warn("Error unregistered server");
         }
 
         initialiseBoatPositions();

src/main/java/seng302/gameServer/ServerAdvertiser.java

@@ -6,20 +6,45 @@ import java.io.IOException;
 import java.net.InetAddress;
 import java.util.Hashtable;
 
+/**
+ * Advertises the game server on the local network
+ */
 public class ServerAdvertiser {
+    /*
+    Our service name & protocol
+
+    This must be in the format _Service._Proto.Name as per http://www.ietf.org/rfc/rfc2782.txt
+    Where Service is unique on the network, and protocol is usually _tcp.
+
+    The pseudo-domain 'local.' must end in a full-stop. This is used to indicate that
+    the lookup should be performed using an IP multicast query on the local IP network.
+
+    Read this before changing any of the following values
+    https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/NetServices/Articles/domainnames.html#//apple_ref/doc/uid/TP40002460-SW1
+     */
     private static String SERVICE = "_partyatsea";
     private static String PROTOCOL = "_tcp";
     public static String SERVICE_TYPE = SERVICE + "." + PROTOCOL + ".local.";
-    private static Integer PROTO_VERSION = 1;
-
 
     private static ServerAdvertiser instance = null;
     private static JmDNS jmdnsInstance = null;
+    private ServiceInfo serviceInfo; // Note: Whenever this is changed, our service will be re-registered on the network.
+
+    private Hashtable<String ,String> props;
 
     private ServerAdvertiser() throws IOException{
         jmdnsInstance = JmDNS.create(InetAddress.getLocalHost());
+
+        props = new Hashtable<>();
+        props.put("map", "");
+        props.put("spacesLeft", "0");
     }
 
+    /**
+     * Get an instance of the ServerAdvertiser, create an instance if there isn't already one
+     * @return A ServerAdvertiser Instance
+     * @throws IOException If there was an exception creating the instance
+     */
     public static ServerAdvertiser getInstance() throws IOException {
         if (instance == null){
             instance = new ServerAdvertiser();
@@ -28,13 +53,47 @@ public class ServerAdvertiser {
         return instance;
     }
 
-    public void registerGame(Integer portNo, String serverName, Integer spacesLeft, String mapName) {
-        Hashtable<String ,String> props = new Hashtable<>();
+    /**
+     * Set the map name & broadcast an update on the network
+     * @param mapName The new map name
+     * @return The current ServerAdvertiser instance
+     */
+    public ServerAdvertiser setMapName(String mapName){
+        props.replace("map", mapName);
 
-        props.put("map", mapName);
-        props.put("spacesLeft", spacesLeft.toString());
+        if (serviceInfo != null){
+            serviceInfo.setText(props);
+        }
 
-        ServiceInfo serviceInfo = ServiceInfo.create(SERVICE_TYPE, serverName, portNo, 0, 0, props);
+        return instance;
+    }
+
+    /**
+     * Set the spaces left on the server & broadcast an update on the network
+     * @param spacesLeft The number of spaces left on the server
+     * @return The current ServerAdvertiser instance
+     */
+    public ServerAdvertiser setSpacesLeft(Integer spacesLeft){
+        props.replace("spacesLeft", spacesLeft.toString());
+
+        if (serviceInfo != null){
+            serviceInfo.setText(props);
+        }
+
+        return instance;
+    }
+
+    /**
+     * Register this service on the network
+     *
+     * Note: other parameters (map name/spaces left etc) are set after the
+     * service has been registered
+     * @param portNo The servers port number
+     * @param serverName The servers name
+     */
+    public void registerGame(Integer portNo, String serverName) {
+
+        serviceInfo = ServiceInfo.create(SERVICE_TYPE, serverName, portNo, 0, 0, props);
 
         new java.util.Timer().schedule(
             new java.util.TimerTask() {
@@ -46,12 +105,14 @@ public class ServerAdvertiser {
                         System.out.println("Failed");
                     }
                 }
-            }, 0
-        );
+            }, 0);
     }
 
+    /**
+     * Unregister the service
+     */
     public void unregister(){
-        jmdnsInstance.unregisterAllServices();
-        jmdnsInstance = null;
+        if (serviceInfo != null)
+            jmdnsInstance.unregisterService(serviceInfo);
     }
 }

src/main/java/seng302/gameServer/ServerDescription.java

@@ -3,7 +3,6 @@ package seng302.gameServer;
 public class ServerDescription {
     private String address;
     private Integer portNum;
-
     private String serverName;
     private String mapName;
     private Integer spacesLeft;
@@ -36,4 +35,39 @@ public class ServerDescription {
     public Integer spacesLeft() {
         return spacesLeft;
     }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == null) {
+            return false;
+        }
+        if (!ServerDescription.class.isAssignableFrom(obj.getClass())) {
+            return false;
+        }
+        final ServerDescription other = (ServerDescription) obj;
+
+        if (!this.getAddress().equals(other.getAddress()) ) {
+            return false;
+        }
+
+        if (!this.portNumber().equals(other.portNumber())){
+            return false;
+        }
+
+        if (!this.getMapName().equals(other.getMapName())){
+            return false;
+        }
+
+        if (!this.getName().equals(other.getName())){
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return this.getName().hashCode() + this.getAddress().hashCode() +
+                this.portNumber().hashCode() + this.getMapName().hashCode();
+    }
 }

src/main/java/seng302/gameServer/ServerToClientThread.java

@@ -1,59 +1,24 @@
 package seng302.gameServer;
 
 
-import java.io.BufferedReader;
-import java.io.ByteArrayOutputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
-import java.io.OutputStream;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import seng302.gameServer.messages.*;
+import seng302.model.Player;
+import seng302.model.ServerYacht;
+import seng302.model.stream.packets.PacketType;
+import seng302.model.stream.packets.StreamPacket;
+import seng302.model.stream.xml.generator.Race;
+import seng302.utilities.XMLGenerator;
+
+import java.io.*;
 import java.net.Socket;
 import java.net.SocketException;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
-import java.util.Observable;
-import java.util.Observer;
+import java.util.*;
 import java.util.concurrent.ThreadLocalRandom;
 import java.util.stream.Collectors;
 import java.util.zip.CRC32;
 import java.util.zip.Checksum;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import seng302.gameServer.messages.BoatAction;
-import seng302.gameServer.messages.BoatLocationMessage;
-import seng302.gameServer.messages.ClientType;
-import seng302.gameServer.messages.CustomizeRequestType;
-import seng302.gameServer.messages.Message;
-import seng302.gameServer.messages.RegistrationResponseMessage;
-import seng302.gameServer.messages.RegistrationResponseStatus;
-import seng302.gameServer.messages.XMLMessage;
-import seng302.gameServer.messages.XMLMessageSubType;
-import seng302.gameServer.messages.YachtEventCodeMessage;
-import seng302.gameServer.messages.YachtEventCodeMessage;
-import seng302.model.Player;
-import seng302.model.ServerYacht;
-import seng302.model.stream.packets.PacketType;
-import seng302.model.stream.packets.StreamPacket;
-import seng302.model.stream.xml.generator.Race;
-import seng302.model.stream.xml.generator.Regatta;
-import seng302.utilities.XMLGenerator;
-import seng302.gameServer.messages.BoatAction;
-import seng302.gameServer.messages.BoatLocationMessage;
-import seng302.gameServer.messages.ClientType;
-import seng302.gameServer.messages.Message;
-import seng302.gameServer.messages.RegistrationResponseMessage;
-import seng302.gameServer.messages.RegistrationResponseStatus;
-import seng302.gameServer.messages.XMLMessage;
-import seng302.gameServer.messages.XMLMessageSubType;
-import seng302.gameServer.messages.YachtEventCodeMessage;
-import seng302.model.Player;
-import seng302.model.ServerYacht;
-import seng302.model.stream.packets.PacketType;
-import seng302.model.stream.packets.StreamPacket;
-import seng302.model.stream.xml.generator.Race;
-import seng302.model.stream.xml.generator.Regatta;
-import seng302.utilities.XMLGenerator;
 
 /**
  * A class describing a single connection to a Client for the purposes of sending and receiving on
@@ -258,12 +223,6 @@ public class ServerToClientThread implements Runnable, Observer {
             race.addBoat(yacht);
         }
 
-        //@TODO calculate lat/lng values
-        xml.setRegatta(
-            new Regatta(
-                "Party Parrot Test Server", "Bermuda Test Course",
-                57.6679590, 11.8503233)
-        );
         xml.setRace(race);
 
         XMLMessage xmlMessage;