README.ja.md

ItemCooldownUtil

アイテムのクールダウンを扱うユーティリティークラスです。

Minecraft 1.9にて、エンダーパールなどのアイテムに対してクールダウンが実装されました。 そのクールダウンを任意のアイテムに対して設定したり、 アイテムがクールダウン中か確認することが出来るメソッドが実装されています。

動作環境

確認はしてないけれども、動くはずの環境です。

• Java 6以降
• CraftBukkit 1.9以降(Spigot等のCraftBukkitフォークを含む)
• Minecraft Client 1.9以降

動作確認環境

• Java 8(1.8.0_77)
• Spigot 1.9.2(git-Spigot-5a40365-b70058a)
• Minecraft Client 1.9.2 (with OptiFine)

例

import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.block.Action;
import org.bukkit.event.player.PlayerInteractEvent;
import org.bukkit.plugin.java.JavaPlugin;

/**
 * @author misterT2525
 */
public class TestPlugin extends JavaPlugin implements Listener {

    @Override
    public void onEnable() {
        Bukkit.getPluginManager().registerEvents(this, this);
    }

    @Override
    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
        if (!(sender instanceof Player)) {
            sender.sendMessage(ChatColor.RED + "This command is only executable from Player.");
            return false;
        }
        if (args.length != 1) {
            sender.sendMessage(ChatColor.RED + "Usage: /" + command.getName() + " <ticks>");
            return false;
        }
        int ticks;
        try {
            ticks = Integer.valueOf(args[0]);
        } catch (NumberFormatException e) {
            sender.sendMessage(ChatColor.RED + "Invalid number.");
            return false;
        }
        Player player = ((Player) sender);
        ItemCooldownUtil.setCooldown(player, player.getInventory().getItemInMainHand().getType(), ticks);
        return true;
    }

    @EventHandler
    @SuppressWarnings("unused")
    public void onInteract(PlayerInteractEvent event) {
        if (event.getAction() != Action.RIGHT_CLICK_AIR && event.getAction() != Action.RIGHT_CLICK_BLOCK) {
            return;
        }
        if (!event.hasItem()) {
            return;
        }

        Player player = event.getPlayer();

        if (ItemCooldownUtil.inCooldown(player, event.getItem().getType())) {
            player.sendMessage(ChatColor.RED + "クールダウン中です。");
        }
    }
}

発生する例外について

NullPointerException

このクラスの全てのメソッドは、引数にnullを渡されないことを想定しています。 その為、引数にnullが渡された場合にNullPointerExceptionが発生します。

IllegalArgumentException

引数にアイテムではないMaterialを渡した場合にIllegalArgumentExceptionが発生します。

RuntimeException

上記２つではないRuntimeExceptionは、主にこのユーティリティーが動作しない環境で呼ばれた場合に発生します。 もしも、1.9以降の環境で発生した場合には、不具合の可能性があるので連絡してくれると助かります。

連絡先

作者Twitter(@misterT2525)まで

ItemCooldownUtil.java

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2016 misterT2525
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package net.mistert2525.itemcooldownutil;// You can move to your package.

import org.bukkit.Bukkit;
import org.bukkit.Material;
import org.bukkit.entity.Player;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Arrays;

/**
 * Utility class for item cool-down
 * <p>
 * https://gist.github.com/misterT2525/56671488127d6a5e8cc7
 *
 * @author misterT2525
 */
public final class ItemCooldownUtil {

    public static void setCooldown(Player player, Material item, int ticks) throws NullPointerException, IllegalArgumentException {
        if (player == null) throw new NullPointerException("player");
        if (item == null) throw new NullPointerException("item");

        Object internalItem = convertItem(item);
        if (internalItem == null) throw new IllegalArgumentException("item");

        invokeMethod(getSetCooldownMethod(), getItemCooldown(player), internalItem, ticks);
    }

    public static boolean inCooldown(Player player, Material item) throws NullPointerException, IllegalArgumentException {
        if (player == null) throw new NullPointerException("player");
        if (item == null) throw new NullPointerException("item");

        Object internalItem = convertItem(item);
        if (internalItem == null) throw new IllegalArgumentException("item");

        return (Boolean) invokeMethod(getInCooldownMethod(), getItemCooldown(player), internalItem);
    }

    /*========== Internal ==========*/

    private static Method GET_HANDLE;
    private static Method GET_ITEM_COOLDOWN;
    private static Method CONVERT_ITEM;

    private static Object getItemCooldown(Player player) {
        if (GET_HANDLE == null)
            GET_HANDLE = getMethodByName(getCraftBukkitClass("entity.CraftPlayer"), "getHandle");
        Object handle = invokeMethod(GET_HANDLE, player);

        if (GET_ITEM_COOLDOWN == null)
            GET_ITEM_COOLDOWN = getMethodByTypes(getMinecraftClass("EntityHuman"), "getItemCooldown", getItemCooldownClass());
        return invokeMethod(GET_ITEM_COOLDOWN, handle);
    }

    private static Object convertItem(Material item) {
        if (CONVERT_ITEM == null)
            CONVERT_ITEM = getMethodByName(getCraftBukkitClass("util.CraftMagicNumbers"), "getItem", Material.class);
        return invokeMethod(CONVERT_ITEM, null, item);
    }

    private static Method SET_COOLDOWN;
    private static Method IN_COOLDOWN;
    private static Class<?> ITEM_COOLDOWN_CLASS;
    private static Class<?> ITEM_CLASS;

    private static Method getSetCooldownMethod() {
        if (SET_COOLDOWN == null)
            SET_COOLDOWN = getMethodByTypes(getItemCooldownClass(), "setCooldown", void.class, getItemClass(), int.class);
        return SET_COOLDOWN;
    }

    private static Method getInCooldownMethod() {
        if (IN_COOLDOWN == null)
            IN_COOLDOWN = getMethodByTypes(getItemCooldownClass(), "inCooldown", boolean.class, getItemClass());
        return IN_COOLDOWN;
    }

    private static Class<?> getItemCooldownClass() {
        if (ITEM_COOLDOWN_CLASS == null)
            ITEM_COOLDOWN_CLASS = getMinecraftClass("ItemCooldown");
        return ITEM_COOLDOWN_CLASS;
    }

    private static Class<?> getItemClass() {
        if (ITEM_CLASS == null)
            ITEM_CLASS = getMinecraftClass("Item");
        return ITEM_CLASS;
    }

    /*========== Reflection ==========*/

    private static String OBC_PACKAGE;
    private static String NMS_PACKAGE;

    private static Class<?> getCraftBukkitClass(String name) {
        if (OBC_PACKAGE == null)
            OBC_PACKAGE = Bukkit.getServer().getClass().getPackage().getName() + ".";
        return getClass(OBC_PACKAGE + name);
    }

    private static Class<?> getMinecraftClass(String name) {
        if (OBC_PACKAGE == null)
            OBC_PACKAGE = Bukkit.getServer().getClass().getPackage().getName() + ".";
        if (NMS_PACKAGE == null)
            NMS_PACKAGE = OBC_PACKAGE.replace("org.bukkit.craftbukkit", "net.minecraft.server");
        return getClass(NMS_PACKAGE + name);
    }

    private static Class<?> getClass(String name) {
        try {
            return Class.forName(name);
        } catch (ClassNotFoundException e) {
            throw new RuntimeException("Unable to find " + name, e);
        }
    }

    private static Method getMethodByName(Class<?> clazz, String name, Class<?>... parameterTypes) {
        try {
            return clazz.getDeclaredMethod(name, parameterTypes);
        } catch (NoSuchMethodException e) {
            throw new RuntimeException("Unable to find " + buildMethodString(clazz, name, null, parameterTypes));
        }
    }

    private static Method getMethodByTypes(Class<?> clazz, String name, Class<?> returnType, Class<?>... parameterTypes) {
        for (Method method : clazz.getDeclaredMethods()) {
            if (!Modifier.isPublic(method.getModifiers())) {
                continue;
            }
            if (method.getReturnType().equals(returnType) && Arrays.equals(method.getParameterTypes(), parameterTypes)) {
                return method;
            }
        }
        throw new RuntimeException("Unable to find " + buildMethodString(clazz, name, returnType, parameterTypes));
    }

    private static Object invokeMethod(Method method, Object object, Object... args) {
        try {
            return method.invoke(object, args);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        } catch (InvocationTargetException e) {
            throw new RuntimeException(e);
        }
    }

    private static String buildMethodString(Class<?> clazz, String name, Class<?> returnType, Class<?>... parameterTypes) {
        StringBuilder sb = new StringBuilder(clazz.getSimpleName()).append('#').append(name).append('(');
        boolean firstParameter = true;
        for (Class<?> parameterType : parameterTypes) {
            if (firstParameter) {
                firstParameter = false;
            } else {
                sb.append(", ");
            }
            sb.append(parameterType.getSimpleName());
        }
        sb.append(')');
        if (returnType != null) {
            sb.append(": ").append(returnType.getSimpleName());
        }
        return sb.toString();
    }

    private ItemCooldownUtil() {
    }
}