Resolves issue #155, resolves issue #154, resolves issue #107

game/src/main/org/apollo/game/model/area/Region.java

@@ -2,11 +2,11 @@ package org.apollo.game.model.area;
 
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -76,7 +76,7 @@ public final class Region {
 	/**
 	 * The Map of Positions to Entities in that Position.
 	 */
-	private final Map<Position, Set<Entity>> entities = new HashMap<>();
+	private final Map<Position, Set<Entity>> entities = new ConcurrentHashMap<>();
 
 	/**
 	 * A List of RegionListeners registered to this Region.

game/src/main/org/apollo/game/service/GameService.java

@@ -119,7 +119,7 @@ public final class GameService extends Service {
 	 *
 	 * @param player The player.
 	 */
-	public void finalizePlayerRegistration(Player player) {
+	public synchronized void finalizePlayerRegistration(Player player) {
 		world.register(player);
 		Region region = world.getRegionRepository().fromPosition(player.getPosition());
 		region.addEntity(player);
@@ -150,7 +150,7 @@ public final class GameService extends Service {
 	/**
 	 * Called every pulse.
 	 */
-	public void pulse() {
+	public synchronized void pulse() {
 		finalizeRegistrations();
 		finalizeUnregistrations();