-Misc clean up/refactor.

-Removed unnecessary Map.containsKey calls
-Using java 8 methods where possible to avoid external checks.

Source L2J HighFive branch:
9d0fee8537

trunk/java/com/l2jserver/gameserver/instancemanager/AntiFeedManager.java

@@ -154,15 +154,9 @@ public final class AntiFeedManager
 		}
 		
 		final Integer addrHash = Integer.valueOf(client.getConnectionAddress().hashCode());
-		int limit = max;
-		if (Config.L2JMOD_DUALBOX_CHECK_WHITELIST.containsKey(addrHash))
-		{
-			limit += Config.L2JMOD_DUALBOX_CHECK_WHITELIST.get(addrHash);
-		}
-		
 		final AtomicInteger connectionCount = event.computeIfAbsent(addrHash, k -> new AtomicInteger());
 		
-		return connectionCount.getAndIncrement() < limit;
+		return connectionCount.getAndIncrement() < (max + Config.L2JMOD_DUALBOX_CHECK_WHITELIST.getOrDefault(addrHash, 0));
 	}
 	
 	/**