Fix race conditions, NPEs and command logic in ItemManager

modules/ItemManager/src/main/java/com/mcatk/itemmanager/ItemManagerCommand.java

@@ -4,12 +4,11 @@
 import org.bukkit.command.CommandExecutor;
 import org.bukkit.command.CommandSender;
 import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
 
 public class ItemManagerCommand implements CommandExecutor {
-    private CommandSender sender;
-    private String[] args;
 
-    void printHelp() {
+    void printHelp(CommandSender sender) {
         sender.sendMessage("帮助：严格按照格式执行");
         sender.sendMessage("创建类型: /im create <类型ID>");
         sender.sendMessage("加入物品: /im add <类型ID> <商品ID>");
@@ -22,54 +21,75 @@ public boolean onCommand(CommandSender sender, Command command, String label, St
         if (!sender.isOp()) {
             return false;
         }
-        this.sender = sender;
-        this.args = args;
         if (args.length == 0) {
-            printHelp();
+            printHelp(sender);
             return true;
         }
         switch (args[0].toLowerCase()) {
             case "create":
-                create();
+                create(sender, args);
                 break;
             case "add":
-                add();
+                add(sender, args);
                 break;
-            case "give":
-                give();
+            case "get":
+                get(sender, args);
                 break;
             case "list":
-                list();
+                list(sender);
                 break;
             default:
         }
         return true;
     }
 
-    private void create() {
+    private void create(CommandSender sender, String[] args) {
+        if (args.length < 2) {
+            sender.sendMessage("参数不足: /im create <类型ID>");
+            return;
+        }
         String sortId = args[1];
         ItemManager.getItemSort().createSort(sortId);
         sender.sendMessage("Ok");
     }
 
-    private void add() {
+    private void add(CommandSender sender, String[] args) {
+        if (args.length < 3) {
+            sender.sendMessage("参数不足: /im add <类型ID> <商品ID>");
+            return;
+        }
+        if (!(sender instanceof Player)) {
+            sender.sendMessage("只有玩家可以执行此命令");
+            return;
+        }
         String sortId = args[1];
         String itemId = args[2];
         ItemManager.getItemSort().addItem(sortId, itemId,
                 ((Player) sender).getInventory().getItemInMainHand());
         sender.sendMessage("Ok");
     }
 
-    private void give() {
+    private void get(CommandSender sender, String[] args) {
+        if (args.length < 3) {
+            sender.sendMessage("参数不足: /im get <类型ID> <商品ID>");
+            return;
+        }
+        if (!(sender instanceof Player)) {
+            sender.sendMessage("只有玩家可以执行此命令");
+            return;
+        }
         String sortId = args[1];
         String itemId = args[2];
-        ((Player) sender).getInventory().addItem(
-                ItemManager.getItemSort().getItem(sortId, itemId)
-        );
-        sender.sendMessage("Ok");
+        ItemStack item = ItemManager.getItemSort().getItem(sortId, itemId);
+        if (item != null) {
+            ((Player) sender).getInventory().addItem(item);
+            sender.sendMessage("Ok");
+        } else {
+            sender.sendMessage("物品不存在");
+        }
     }
 
-    private void list() {
+    private void list(CommandSender sender) {
         sender.sendMessage(ItemManager.getItemSort().listAll());
     }
 

modules/ItemManager/src/main/java/com/mcatk/itemmanager/ItemSort.java

@@ -32,6 +32,9 @@ public void addItem(String id1, String id2, ItemStack itemStack) {
     }
 
     public ItemStack getItem(String id1, String id2) {
+        if (!itemsHashMap.containsKey(id1)) {
+            return null;
+        }
         return itemsHashMap.get(id1).getItemStackHashMap().get(id2);
     }