Added MAX_PLAYER and MAX_PLAYER_MESSAGE flags

Allows setting maximum number of players in a region
and sends a message if a region is at capacity.

src/main/java/com/sk89q/worldguard/bukkit/WorldGuardPlayerListener.java

@@ -89,7 +89,9 @@ public void onPlayerMove(PlayerMoveEvent event) {
             ConfigurationManager cfg = plugin.getGlobalStateManager();
             WorldConfiguration wcfg = cfg.get(world);
 
-            if (player.getVehicle() != null) return; // handled in vehicle listener
+            if (player.getVehicle() != null) {
+                return; // handled in vehicle listener
+            }
             if (wcfg.useRegions) {
                 // Did we move a block?
                 if (event.getFrom().getBlockX() != event.getTo().getBlockX()
@@ -110,9 +112,34 @@ public void onPlayerMove(PlayerMoveEvent event) {
                     Vector pt = new Vector(event.getTo().getBlockX(), event.getTo().getBlockY(), event.getTo().getBlockZ());
                     ApplicableRegionSet set = mgr.getApplicableRegions(pt);
 
+                    // check if region is full
+                    Integer maxPlayers = set.getFlag(DefaultFlag.MAX_PLAYERS);
+                    boolean regionFull = false;
+                    String maxPlayerMessage = null;
+                    if (maxPlayers != null && !hasBypass) {
+                        for (ProtectedRegion region : set) {
+                            int occupantCount = 0;
+                            for(Player occupant : world.getPlayers()) {
+                                // Make sure you're not checking the same player
+                                // A person with bypass doesn't count as an occupant of the region
+                                if (!occupant.equals(player) && !plugin.getGlobalRegionManager().hasBypass(occupant, world)) {
+                                    if (region.contains(BukkitUtil.toVector(occupant.getLocation()))) {
+                                        if (++occupantCount >= maxPlayers) {
+                                            regionFull = true;
+                                            maxPlayerMessage = region.getFlag(DefaultFlag.MAX_PLAYERS_MESSAGE);
+                                            break;
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                    }
+
                     boolean entryAllowed = set.allows(DefaultFlag.ENTRY, localPlayer);
-                    if (!hasBypass && !entryAllowed) {
+                    if (!hasBypass && (!entryAllowed || regionFull)) {
-                        player.sendMessage(ChatColor.DARK_RED + "You are not permitted to enter this area.");
+                        String message = maxPlayerMessage != null ? maxPlayerMessage : "You are not permitted to enter this area.";
+
+                        player.sendMessage(ChatColor.DARK_RED + message);
 
                         Location newLoc = event.getFrom();
                         newLoc.setX(newLoc.getBlockX() + 0.5);

src/main/java/com/sk89q/worldguard/protection/flags/DefaultFlag.java

@@ -71,6 +71,7 @@ public final class DefaultFlag {
     public static final StateFlag POTION_SPLASH = new StateFlag("potion-splash", true);
     public static final StringFlag GREET_MESSAGE = new StringFlag("greeting", RegionGroup.ALL);
     public static final StringFlag FAREWELL_MESSAGE = new StringFlag("farewell", RegionGroup.ALL);
+    public static final StringFlag MAX_PLAYERS_MESSAGE = new StringFlag("max-players-reject-message", RegionGroup.ALL);
     public static final BooleanFlag NOTIFY_ENTER = new BooleanFlag("notify-enter", RegionGroup.ALL);
     public static final BooleanFlag NOTIFY_LEAVE = new BooleanFlag("notify-leave", RegionGroup.ALL);
     public static final SetFlag<EntityType> DENY_SPAWN = new SetFlag<EntityType>("deny-spawn", RegionGroup.ALL, new EntityTypeFlag(null));
@@ -83,6 +84,7 @@ public final class DefaultFlag {
     public static final IntegerFlag FEED_AMOUNT = new IntegerFlag("feed-amount", RegionGroup.ALL);
     public static final IntegerFlag MIN_FOOD = new IntegerFlag("feed-min-hunger", RegionGroup.ALL);
     public static final IntegerFlag MAX_FOOD = new IntegerFlag("feed-max-hunger", RegionGroup.ALL);
+    public static final IntegerFlag MAX_PLAYERS = new IntegerFlag("max-players-allowed", RegionGroup.ALL);
     public static final LocationFlag TELE_LOC = new LocationFlag("teleport", RegionGroup.MEMBERS);
     public static final LocationFlag SPAWN_LOC = new LocationFlag("spawn", RegionGroup.MEMBERS);
     public static final BooleanFlag BUYABLE = new BooleanFlag("buyable");
@@ -97,7 +99,7 @@ public final class DefaultFlag {
         CREEPER_EXPLOSION, ENDERDRAGON_BLOCK_DAMAGE, GHAST_FIREBALL, ENDER_BUILD,
         GREET_MESSAGE, FAREWELL_MESSAGE, NOTIFY_ENTER, NOTIFY_LEAVE,
         EXIT, ENTRY, LIGHTNING, ENTITY_PAINTING_DESTROY,
-        ENTITY_ITEM_FRAME_DESTROY, ITEM_DROP,
+        ENTITY_ITEM_FRAME_DESTROY, ITEM_DROP, MAX_PLAYERS, MAX_PLAYERS_MESSAGE,
         HEAL_AMOUNT, HEAL_DELAY, MIN_HEAL, MAX_HEAL,
         FEED_DELAY, FEED_AMOUNT, MIN_FOOD, MAX_FOOD,
         SNOW_FALL, SNOW_MELT, ICE_FORM, ICE_MELT, GAME_MODE,