com.comphenix.pulse.Button.java Source code

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Here is the source code for com.comphenix.pulse.Button.java

Source

/*
 *  PulseExtenderMod - Allows you to customize the duration a button is down in Bukkit.
 *  Copyright (C) 2012 Kristian S. Stangeland
 *
 *  This program is free software; you can redistribute it and/or modify it under the terms of the 
 *  GNU General Public License as published by the Free Software Foundation; either version 2 of 
 *  the License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 
 *  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
 *  See the GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along with this program; 
 *  if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 
 *  02111-1307 USA
 */

package com.comphenix.pulse;

import java.lang.reflect.Method;
import java.util.Random;

import net.minecraft.server.BlockButton;
import net.minecraft.server.World;
import net.minecraft.server.WorldServer;

import org.apache.commons.lang.ArrayUtils;
import org.bukkit.block.Block;
import org.bukkit.craftbukkit.CraftWorld;

public class Button {

    private static final int pressedBit = 0x8;

    // Whether or not to completely ignore CraftBukkit-only methods
    private static boolean disableDirectAccess;
    private static boolean useReflection;

    // The underlying block
    private Block block;

    // Reflection method to call
    private static Method updateMethod;

    public Button(Block block) {
        this.block = block;
    }

    public boolean isPressed() {
        return (block.getData() & pressedBit) != 0;
    }

    public void setPressed(boolean state, boolean updatePhysics) {

        byte data = block.getData();

        // Set bit
        if (state)
            data |= pressedBit;
        else
            data &= ~pressedBit;

        block.setData(data, updatePhysics);
    }

    public void updateTick() {

        // Guard
        if (disableDirectAccess) {
            return;
        }

        Random ignored = new Random();

        try {

            CraftWorld craftWorld = (CraftWorld) block.getWorld();
            WorldServer server = craftWorld.getHandle();
            BlockButton notchButton = (BlockButton) net.minecraft.server.Block.byId[77];

            try {
                // Try to call the method directly
                if (!useReflection) {
                    notchButton.b(server, block.getX(), block.getY(), block.getZ(), ignored);
                    return;
                }

            } catch (NoSuchMethodError e) {
                // Nope, didn't work.
                useReflection = true;
            }

            if (updateMethod == null) {
                updateMethod = findObsfucatedMethod(BlockButton.class);
            }

            // Call this method
            updateMethod.invoke(notchButton, (World) server, block.getX(), block.getY(), block.getZ(), ignored);

        } catch (Exception ex) {
            System.err.println("Incompatible CraftBukkit version! " + ex.getMessage());
            ex.printStackTrace();
            disableDirectAccess = true;
        }
    }

    private Method findObsfucatedMethod(Class<BlockButton> clazz) {

        Class<?>[] expected = new Class<?>[] { World.class, int.class, int.class, int.class, Random.class };

        // Find the correct method to call
        for (Method method : clazz.getMethods()) {
            if (ArrayUtils.isEquals(method.getParameterTypes(), expected)) {
                return method;
            }
        }

        // Damn
        throw new RuntimeException("Unable to find updateTick-method in BlockButton.");
    }

    /**
     * Retrieves the block this button is standing on.
     * @return The block the button is standing on.
     */
    public Block getOffset() {

        int data = block.getData() & 0x7;

        if (data == 1) {
            return block.getRelative(-1, 0, 0);
        } else if (data == 2) {
            return block.getRelative(1, 0, 0);
        } else if (data == 3) {
            return block.getRelative(0, 0, -1);
        } else if (data == 4) {
            return block.getRelative(0, 0, 1);
        } else {
            return block.getRelative(0, -1, 0);
        }
    }
}