Java tutorial
/* * This file is part of Applied Energistics 2. * Copyright (c) 2013 - 2014, AlgorithmX2, All rights reserved. * * Applied Energistics 2 is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * Applied Energistics 2 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 Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with Applied Energistics 2. If not, see <http://www.gnu.org/licenses/lgpl>. */ package appeng.transformer.asm; import java.util.Iterator; import javax.annotation.Nullable; import com.google.common.collect.HashMultimap; import com.google.common.collect.Multimap; import org.apache.logging.log4j.Level; import org.objectweb.asm.ClassReader; import org.objectweb.asm.ClassWriter; import org.objectweb.asm.Opcodes; import org.objectweb.asm.tree.AbstractInsnNode; import org.objectweb.asm.tree.ClassNode; import org.objectweb.asm.tree.InsnNode; import org.objectweb.asm.tree.MethodInsnNode; import org.objectweb.asm.tree.MethodNode; import org.objectweb.asm.tree.VarInsnNode; import net.minecraft.launchwrapper.IClassTransformer; import cpw.mods.fml.relauncher.FMLRelaunchLog; import appeng.helpers.Reflected; @Reflected public final class ASMTweaker implements IClassTransformer { private static final String[] EXCEPTIONS = new String[0]; private final Multimap<String, PublicLine> privateToPublicMethods = HashMultimap.create(); @Reflected public ASMTweaker() { this.privateToPublicMethods.put("net.minecraft.client.gui.inventory.GuiContainer", new PublicLine("func_146977_a", "(Lnet/minecraft/inventory/Slot;)V")); this.privateToPublicMethods.put("net.minecraft.client.gui.inventory.GuiContainer", new PublicLine("a", "(Lzk;)V")); this.privateToPublicMethods.put("appeng.tile.AEBaseTile", new PublicLine("writeToNBT", "(Lnet/minecraft/nbt/NBTTagCompound;)V")); this.privateToPublicMethods.put("appeng.tile.AEBaseTile", new PublicLine("func_145841_b", "(Lnet/minecraft/nbt/NBTTagCompound;)V")); this.privateToPublicMethods.put("appeng.tile.AEBaseTile", new PublicLine("b", "(Ldh;)V")); this.privateToPublicMethods.put("appeng.tile.AEBaseTile", new PublicLine("readFromNBT", "(Lnet/minecraft/nbt/NBTTagCompound;)V")); this.privateToPublicMethods.put("appeng.tile.AEBaseTile", new PublicLine("func_145839_a", "(Lnet/minecraft/nbt/NBTTagCompound;)V")); this.privateToPublicMethods.put("appeng.tile.AEBaseTile", new PublicLine("a", "(Ldh;)V")); } @Nullable @Override public byte[] transform(String name, String transformedName, byte[] basicClass) { if (basicClass == null) { return null; } try { if (transformedName != null && this.privateToPublicMethods.containsKey(transformedName)) { ClassNode classNode = new ClassNode(); ClassReader classReader = new ClassReader(basicClass); classReader.accept(classNode, 0); for (PublicLine set : this.privateToPublicMethods.get(transformedName)) { this.makePublic(classNode, set); } // CALL VIRTUAL! if (transformedName.equals("net.minecraft.client.gui.inventory.GuiContainer")) { for (MethodNode mn : classNode.methods) { if (mn.name.equals("func_146977_a") || (mn.name.equals("a") && mn.desc.equals("(Lzk;)V"))) { MethodNode newNode = new MethodNode(Opcodes.ACC_PUBLIC, "func_146977_a_original", mn.desc, mn.signature, EXCEPTIONS); newNode.instructions.add(new VarInsnNode(Opcodes.ALOAD, 0)); newNode.instructions.add(new VarInsnNode(Opcodes.ALOAD, 1)); newNode.instructions.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, classNode.name, mn.name, mn.desc, false)); newNode.instructions.add(new InsnNode(Opcodes.RETURN)); this.log(newNode.name + newNode.desc + " - New Method"); classNode.methods.add(newNode); break; } } for (MethodNode mn : classNode.methods) { if (mn.name.equals("func_73863_a") || mn.name.equals("drawScreen") || (mn.name.equals("a") && mn.desc.equals("(IIF)V"))) { Iterator<AbstractInsnNode> i = mn.instructions.iterator(); while (i.hasNext()) { AbstractInsnNode in = i.next(); if (in.getOpcode() == Opcodes.INVOKESPECIAL) { MethodInsnNode n = (MethodInsnNode) in; if (n.name.equals("func_146977_a") || (n.name.equals("a") && n.desc.equals("(Lzk;)V"))) { this.log(n.name + n.desc + " - Invoke Virtual"); mn.instructions.insertBefore(n, new MethodInsnNode(Opcodes.INVOKEVIRTUAL, n.owner, n.name, n.desc, false)); mn.instructions.remove(in); break; } } } } } } ClassWriter writer = new ClassWriter(ClassWriter.COMPUTE_MAXS); classNode.accept(writer); return writer.toByteArray(); } } catch (Throwable ignored) { } return basicClass; } private void makePublic(ClassNode classNode, PublicLine set) { for (MethodNode mn : classNode.methods) { if (mn.name.equals(set.name) && mn.desc.equals(set.desc)) { mn.access = (mn.access & (~(Opcodes.ACC_FINAL | Opcodes.ACC_PRIVATE | Opcodes.ACC_PROTECTED))) | Opcodes.ACC_PUBLIC; this.log(mn.name + mn.desc + " - Transformed"); } } } private void log(String string) { FMLRelaunchLog.log("AE2-CORE", Level.INFO, string); } private static final class PublicLine { private final String name; private final String desc; public PublicLine(String name, String desc) { this.name = name; this.desc = desc; } } }