Fix mDNS detection of hosts with the same IP address

This is the case for PCs running GFE and Sunshine side-by-side.

app/src/main/java/com/limelight/computers/ComputerManagerService.java

@@ -431,11 +431,6 @@ public class ComputerManagerService extends Service {
                 }
             }
 
-            @Override
-            public void notifyComputerRemoved(MdnsComputer computer) {
-                // Nothing to do here
-            }
-
             @Override
             public void notifyDiscoveryFailure(Exception e) {
                 LimeLog.severe("mDNS discovery failed");

app/src/main/java/com/limelight/discovery/DiscoveryService.java

@@ -54,13 +54,6 @@ public class DiscoveryService extends Service {
                 }
             }
 
-            @Override
-            public void notifyComputerRemoved(MdnsComputer computer) {
-                if (boundListener != null) {
-                    boundListener.notifyComputerRemoved(computer);
-                }
-            }
-
             @Override
             public void notifyDiscoveryFailure(Exception e) {
                 if (boundListener != null) {

app/src/main/java/com/limelight/nvstream/mdns/MdnsDiscoveryAgent.java

@@ -7,7 +7,6 @@ import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.net.NetworkInterface;
 import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 
@@ -25,13 +24,13 @@ public class MdnsDiscoveryAgent implements ServiceListener {
     
     private MdnsDiscoveryListener listener;
     private Thread discoveryThread;
-    private HashMap<InetAddress, MdnsComputer> computers = new HashMap<InetAddress, MdnsComputer>();
+    private HashSet<MdnsComputer> computers = new HashSet<>();
-    private HashSet<String> pendingResolution = new HashSet<String>();
+    private HashSet<String> pendingResolution = new HashSet<>();
     
     // The resolver factory's instance member has a static lifetime which
     // means our ref count and listener must be static also.
     private static int resolverRefCount = 0;
-    private static HashSet<ServiceListener> listeners = new HashSet<ServiceListener>();
+    private static HashSet<ServiceListener> listeners = new HashSet<>();
     private static ServiceListener nvstreamListener = new ServiceListener() {
         @Override
         public void serviceAdded(ServiceEvent event) {
@@ -107,7 +106,7 @@ public class MdnsDiscoveryAgent implements ServiceListener {
                 return false;
             }
         }
-    };
+    }
 
     static {
         // Override jmDNS's default topology discovery class with ours
@@ -261,7 +260,7 @@ public class MdnsDiscoveryAgent implements ServiceListener {
         for (Inet4Address v4Addr : v4Addrs) {
             synchronized (computers) {
                 MdnsComputer computer = new MdnsComputer(info.getName(), v4Addr, v6GlobalAddr, info.getPort());
-                if (computers.put(computer.getLocalAddress(), computer) == null) {
+                if (computers.add(computer)) {
                     // This was a new entry
                     listener.notifyComputerAdded(computer);
                 }
@@ -274,8 +273,7 @@ public class MdnsDiscoveryAgent implements ServiceListener {
 
             if (v6LocalAddr != null || v6GlobalAddr != null) {
                 MdnsComputer computer = new MdnsComputer(info.getName(), v6LocalAddr, v6GlobalAddr, info.getPort());
-                if (computers.put(v6LocalAddr != null ?
+                if (computers.add(computer)) {
-                        computer.getLocalAddress() : computer.getIpv6Address(), computer) == null) {
                     // This was a new entry
                     listener.notifyComputerAdded(computer);
                 }
@@ -353,7 +351,7 @@ public class MdnsDiscoveryAgent implements ServiceListener {
     
     public List<MdnsComputer> getComputerSet() {
         synchronized (computers) {
-            return new ArrayList<MdnsComputer>(computers.values());
+            return new ArrayList<>(computers);
         }
     }
 
@@ -377,28 +375,6 @@ public class MdnsDiscoveryAgent implements ServiceListener {
     @Override
     public void serviceRemoved(ServiceEvent event) {
         LimeLog.info("mDNS: Machine disappeared: "+event.getInfo().getName());
-
-        Inet4Address v4Addrs[] = event.getInfo().getInet4Addresses();
-        for (Inet4Address addr : v4Addrs) {
-            synchronized (computers) {
-                MdnsComputer computer = computers.remove(addr);
-                if (computer != null) {
-                    listener.notifyComputerRemoved(computer);
-                    break;
-                }
-            }
-        }
-
-        Inet6Address v6Addrs[] = event.getInfo().getInet6Addresses();
-        for (Inet6Address addr : v6Addrs) {
-            synchronized (computers) {
-                MdnsComputer computer = computers.remove(addr);
-                if (computer != null) {
-                    listener.notifyComputerRemoved(computer);
-                    break;
-                }
-            }
-        }
     }
 
     @Override

app/src/main/java/com/limelight/nvstream/mdns/MdnsDiscoveryListener.java

@@ -2,6 +2,5 @@ package com.limelight.nvstream.mdns;
 
 public interface MdnsDiscoveryListener {
     void notifyComputerAdded(MdnsComputer computer);
-    void notifyComputerRemoved(MdnsComputer computer);
     void notifyDiscoveryFailure(Exception e);
 }