NMSUtil.java

/**
 * This document a contribution to the Qixalite project.
 */
package com.qixalite.plugins.meguy26.mipayrarbil.minigames.nms;

import org.bukkit.entity.Player;
import org.omg.PortableServer.ThreadPolicyOperations;

import java.lang.reflect.Method;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Created by Meguy26 on 8/6/2015. <p> Package: com.qixalite.plugins.meguy26.mipayrarbil.minigames.nms
 * <p> Project: MingameFramework <p>
 */
public class NMSUtil {
    private static String version;
    private static Class<?> entity;
    private static Class<?> craftPlayer;
    private static Method getPlayerHandle;
    private static Method setInvisible;
    private static boolean setup = false;


    public static void setPlayerInvisible(Player player, boolean invisible) {
        try {
            setupNMS();
            Object playerEntity = entity.cast(
                    getPlayerHandle.invoke(craftPlayer.cast(player), new Class<?>[] {}));
            setInvisible.invoke(playerEntity, invisible);
        } catch (Throwable throwable) {
            throwable.printStackTrace();
        }
    }

    private static void setupNMS() {
        if (! setup) {
            try {
                craftPlayer = getNMSClass("org.bukkit.craftbukkit.%s.entity.CraftPlayer");
                entity = getNMSClass("net.minecraft.server.%s.Entity");
                getPlayerHandle = craftPlayer.getDeclaredMethod("getHandle", new Class<?>[] {});
                setInvisible = entity.getDeclaredMethod("setInvisible", boolean.class);
                setup = true;
            } catch (Throwable throwable) {
                throwable.printStackTrace();
            }
        }
    }

    private static Class<?> getNMSClass(String nmsClass) {
        pullVersion();

        if (version == null) {
            return null;
        }

        try {
            return Class.forName(String.format(nmsClass, version));
        } catch (ClassNotFoundException e) {
            return null;
        }

    }

    private static void pullVersion() {
        if (version == null) {
            Pattern pat = Pattern.compile("net\\.minecraft\\.(?:server)?\\.(v(?:\\d_)+R\\d)");
            for (Package p : Package.getPackages()) {
                String name = p.getName();
                Matcher m = pat.matcher(name);
                if (m.matches()) {
                    version = m.group(1);
                }
            }
        }
    }
}