hellfirepvp.astralsorcery.core.patch.helper.PatchKnockbackEvent.java Source code

Introduction

Here is the source code for hellfirepvp.astralsorcery.core.patch.helper.PatchKnockbackEvent.java

Source

/*******************************************************************************
 * HellFirePvP / Astral Sorcery 2017
 *
 * This project is licensed under GNU GENERAL PUBLIC LICENSE Version 3.
 * The source code is available on github: https://github.com/HellFirePvP/AstralSorcery
 * For further details, see the License file there.
 ******************************************************************************/

package hellfirepvp.astralsorcery.core.patch.helper;

import hellfirepvp.astralsorcery.core.ClassPatch;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.tree.AbstractInsnNode;
import org.objectweb.asm.tree.ClassNode;
import org.objectweb.asm.tree.FieldInsnNode;
import org.objectweb.asm.tree.InsnNode;
import org.objectweb.asm.tree.MethodInsnNode;
import org.objectweb.asm.tree.MethodNode;
import org.objectweb.asm.tree.TypeInsnNode;
import org.objectweb.asm.tree.VarInsnNode;

/**
 * This class is part of the Astral Sorcery Mod
 * The complete source code for this mod can be found on github.
 * Class: PatchKnockbackEvent
 * Created by HellFirePvP
 * Date: 02.12.2016 / 19:02
 */
public class PatchKnockbackEvent extends ClassPatch {

    public PatchKnockbackEvent() {
        super("net.minecraft.entity.EntityLivingBase");
    }

    @Override
    public void patch(ClassNode cn) {
        MethodNode mn = getMethod(cn, "knockBack", "func_70653_a", "(Lnet/minecraft/entity/Entity;FDD)V");
        AbstractInsnNode n = mn.instructions.getFirst();
        mn.instructions.insertBefore(n,
                new FieldInsnNode(Opcodes.GETSTATIC, "net/minecraftforge/common/MinecraftForge", "EVENT_BUS",
                        "Lnet/minecraftforge/fml/common/eventhandler/EventBus;"));
        mn.instructions.insertBefore(n,
                new TypeInsnNode(Opcodes.NEW, "hellfirepvp/astralsorcery/common/event/EntityKnockbackEvent"));
        mn.instructions.insertBefore(n, new InsnNode(Opcodes.DUP));
        mn.instructions.insertBefore(n, new VarInsnNode(Opcodes.ALOAD, 0)); //thisEntity
        mn.instructions.insertBefore(n, new VarInsnNode(Opcodes.ALOAD, 1)); //attackingEntity
        mn.instructions.insertBefore(n, new VarInsnNode(Opcodes.FLOAD, 2)); //str
        mn.instructions.insertBefore(n,
                new MethodInsnNode(Opcodes.INVOKESPECIAL,
                        "hellfirepvp/astralsorcery/common/event/EntityKnockbackEvent", "<init>",
                        "(Lnet/minecraft/entity/EntityLivingBase;Lnet/minecraft/entity/Entity;F)V", false));
        mn.instructions.insertBefore(n,
                new MethodInsnNode(Opcodes.INVOKEVIRTUAL, "net/minecraftforge/fml/common/eventhandler/EventBus",
                        "post", "(Lnet/minecraftforge/fml/common/eventhandler/Event;)Z", false));
        mn.instructions.insertBefore(n, new InsnNode(Opcodes.POP));
    }

}