java - Bukkit - 使用 VaultAPI 的 NPE(聊天)

Question

当尝试从 GUI 设置播放器后缀/前缀时，我收到一个用于设置所述前缀/后缀的空指针异常。 (我收到“您应用了 x 标签”消息，并且它确实关闭了库存。)

主类(定义和设置聊天的地方，而不是整个类)

public static Chat chat = null;
@SuppressWarnings("unused")
private TagsCommands tCmd;

public void onEnable() {
    if (Bukkit.getPluginManager().getPlugin("Vault") != null) {
        setupChat();
        createFolders();
        Message.console("&fPlugin successfully loaded");
        Bukkit.getPluginManager().registerEvents(new TagsGUI(), this);
        tCmd = new TagsCommands(this);
    } else {
        Message.console("&dCouldn't enable plugin as &aVault&c was not found");
        Bukkit.getPluginManager().disablePlugin(this);
        return;
    }
}

private boolean setupChat() {
    RegisteredServiceProvider<Chat> chatProvider = getServer().getServicesManager()
            .getRegistration(net.milkbowl.vault.chat.Chat.class);
    if (chatProvider != null) {
        chat = chatProvider.getProvider();

    }
    return (chat != null);
}

GUI 类(同样，这不是全部。错误位于该类的第 55 行。)

@EventHandler
public void inventoryClick(InventoryClickEvent event) {
    Player player = (Player) event.getWhoClicked();
    ItemStack click = event.getCurrentItem();
    if (opened.contains(player)) {
        event.setCancelled(true);
        File tags = new File("plugins/Tags/Pages", "One.yml");
        FileConfiguration tagsC = YamlConfiguration.loadConfiguration(tags);
        for (String title : tagsC.getConfigurationSection("Tags").getKeys(false)) {
            String tag = tagsC.getString("Tags." + title + ".Display");
            if (click.getItemMeta().getDisplayName().equals(Format.color(tag))) {
                if (player.hasPermission(tagsC.getString("Tags." + title + ".Permission"))) {
                    if (tagsC.getString("Tags." + title + ".Type").equalsIgnoreCase("prefix")) {
                        player.closeInventory();
                        Message.player("&fYou applied the '" + tag + "&f' tag", player);
                        Main.chat.setPlayerPrefix(player, Format.color(tag));
                        break;
                    } else if (tagsC.getString("Tags." + title + ".Type").equalsIgnoreCase("suffix")) {
                        player.closeInventory();
                        Message.player("&fYou applied the '" + tag + "&f' tag", player);
                        Main.chat.setPlayerSuffix(player, Format.color(tag));
                        break;
                    }
                } else {
                    Message.player("&fSorry, but you do not have permission to do this", player);
                    break;
                }
            }
        }
        return;
    }
}

第 55 行:Main.chat.setPlayerSuffix(player, Format.color(tag));

控制台错误消息:

[11:13:05 INFO]: BearToothh issued server command: /tags
[11:13:12 ERROR]: Could not pass event InventoryClickEvent to Tags v1.0
org.bukkit.event.EventException: null
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:500) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:485) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1889) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at net.minecraft.server.v1_12_R1.PacketPlayInWindowClick.a(SourceFile:33) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at net.minecraft.server.v1_12_R1.PacketPlayInWindowClick.a(SourceFile:10) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at net.minecraft.server.v1_12_R1.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:?]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:?]
        at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:748) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:406) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:679) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:577) [spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        at java.lang.Thread.run(Unknown Source) [?:?]
Caused by: java.lang.NullPointerException
        at me.askingg.tags.TagsGUI.inventoryClick(TagsGUI.java:55) ~[?:?]
        at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?]
        at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:?]
        at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:?]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:?]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:302) ~[spigot-1.12.2.jar:git-Spigot-2cf50f0-2b93d83]
        ... 15 more

Answer 1

public static Chat chat = null; 为 null，因此它返回 NullPointerException。您不能定义一个空的聊天并在不存在的聊天上设置前缀和内容^^您必须将 Chat chat 变量定义为现有聊天。