Prevent players from creating itemcases where ones already exist.

src/main/java/com/gmail/bleedobsidian/itemcase/commands/CreateCommand.java

@@ -73,6 +73,16 @@ public final class CreateCommand implements Command {
 
         // Get the players target block.
         target = player.getTargetBlock(null, 3).getLocation();
+        
+        // Check if itemcase already exists here.
+        if(ItemCaseCore.instance.getItemcaseManager().isItemcase(target)) {
+            
+            // Show message.
+            chatLogger.message(player, "command.create.invalid-location");
+            
+            // Exit.
+            return;
+        }
 
         // If target block is not on the list of accepted materials.
         if(!materials.contains(target.getBlock().getType())) {

src/main/java/com/gmail/bleedobsidian/itemcase/managers/ItemcaseManager.java

@@ -24,7 +24,6 @@ import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.OfflinePlayer;
 import org.bukkit.World;
-import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.EventPriority;
 import org.bukkit.event.Listener;
@@ -161,6 +160,29 @@ public final class ItemcaseManager {
                 new ItemcaseManagerListener(), ItemCaseCore.instance);
     }
     
+    /**
+     * If the given location is an itemcase or not.
+     * 
+     * @param location Location.
+     * @return Boolean.
+     */
+    public boolean isItemcase(Location location) {
+        
+        // For every itemcase.
+        for(Itemcase itemcase : this.itemcases) {
+            
+            // Check if location matches.
+            if(itemcase.getLocation().equals(location)) {
+                
+                // Return true.
+                return true;
+            }
+        }
+        
+        // Otherwise return false.
+        return false;
+    }
+    
     /**
      * @return A list of all active Itemcase instances.
      */

src/main/resources/languages/EN.yml

@@ -42,6 +42,10 @@ command:
         # invalid block type.
         invalid-type: "This block cannot be used for an ItemCase."
         
+        # Shown to the player when they try to make an itemcase where one
+        # already exists.
+        invalid-location: "An ItemCase already exists here."
+        
         # Shown to the player when they use the create command but they are not
         # holding any item in their main hand.
         main-hand: "You must be holding something in your main hand."