Java GeneratorAdapter.visitFieldInsn方法代碼示例

import org.objectweb.asm.commons.GeneratorAdapter; //導入方法依賴的package包/類
private static void prepareMethodParameters(GeneratorAdapter mv, String className, List<Type> args, Type returnType, boolean isStatic, int methodId) {
    //第一個參數：new Object[]{...};,如果方法沒有參數直接傳入new Object[0]
    if (args.size() == 0) {
        mv.visitInsn(Opcodes.ICONST_0);
        mv.visitTypeInsn(Opcodes.ANEWARRAY, "java/lang/Object");
    } else {
        createObjectArray(mv, args, isStatic);
    }

    //第二個參數：this,如果方法是static的話就直接傳入null
    if (isStatic) {
        mv.visitInsn(Opcodes.ACONST_NULL);
    } else {
        mv.visitVarInsn(Opcodes.ALOAD, 0);
    }

    //第三個參數：changeQuickRedirect
    mv.visitFieldInsn(Opcodes.GETSTATIC,
            className,
            REDIRECTFIELD_NAME,
            REDIRECTCLASSNAME);

    //第四個參數：false,標誌是否為static
    mv.visitInsn(isStatic ? Opcodes.ICONST_1 : Opcodes.ICONST_0);
    //第五個參數：
    mv.push(methodId);
    //第六個參數：參數class數組
    createClassArray(mv, args);
    //第七個參數：返回值類型class
    createReturnClass(mv, returnType);
}
 

import org.objectweb.asm.commons.GeneratorAdapter; //導入方法依賴的package包/類
/**
 * Pushes in the stack the value that should be redirected for the given local.
 */
protected static void redirectLocal(GeneratorAdapter mv, Type arg) {
    switch (arg.getDescriptor()) {
        case "Z":
            mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Boolean", "TYPE", "Ljava/lang/Class;");
            break;
        case "B":
            mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Byte", "TYPE", "Ljava/lang/Class;");
            break;
        case "C":
            mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Character", "TYPE", "Ljava/lang/Class;");
            break;
        case "S":
            mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Short", "TYPE", "Ljava/lang/Class;");
            break;
        case "I":
            mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Integer", "TYPE", "Ljava/lang/Class;");
            break;
        case "F":
            mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Float", "TYPE", "Ljava/lang/Class;");
            break;
        case "D":
            mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Double", "TYPE", "Ljava/lang/Class;");
            break;
        case "J":
            mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Long", "TYPE", "Ljava/lang/Class;");
            break;
        case "V":
            mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Void", "TYPE", "Ljava/lang/Class;");
            break;
        default:
            mv.visitLdcInsn(Type.getType(arg.getDescriptor()));
    }

}
 

import org.objectweb.asm.commons.GeneratorAdapter; //導入方法依賴的package包/類
@Override
@Unsafe(Unsafe.ASM_API)
public byte[] transform(String name, String transformedName, byte[] basicClass) {
	String srgName = this.srgName;
	if (!AlchemyEngine.isRuntimeDeobfuscationEnabled())
		srgName = DeobfuscatingRemapper.instance().mapMethodName(transformedName, this.srgName, desc);
	AlchemyTransformerManager.transform("<proxy>" + name + "|" + transformedName + "#" + proxyMethod.name + proxyMethod.signature
			+ "\n->  " + target + "#" + srgName + desc);
	ClassReader reader = new ClassReader(basicClass);
	ClassWriter writer = ASMHelper.newClassWriter(ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES);
	ClassNode node = new ClassNode(ASM5);
	reader.accept(node, 0);
	MethodNode oldMethod = null, newMethod = new MethodNode(proxyMethod.access, proxyMethod.name, proxyMethod.desc, proxyMethod.signature,
			proxyMethod.exceptions.toArray(new String[proxyMethod.exceptions.size()]));
	for (MethodNode method : node.methods)
		if (method.name.equals(proxyMethod.name) && method.desc.equals(proxyMethod.desc)) {
			oldMethod = method;
			GeneratorAdapter adapter = new GeneratorAdapter(newMethod, method.access, method.name, method.desc);
			Type owner = Type.getType(ASMHelper.getClassDesc(target));
			Method targetMethod = new Method(srgName, desc);
			switch (opcode) {
				case INVOKESTATIC:
					adapter.loadArgs();
					adapter.invokeStatic(owner, targetMethod);
					break;
				case INVOKEVIRTUAL:
					adapter.loadArgs();
					adapter.invokeVirtual(owner, targetMethod);
					break;
				case INVOKESPECIAL:
					adapter.invokeStatic(Type.getType(AlchemyEngine.class), new Method("lookup",
							"()Ljava/lang/invoke/MethodHandles$Lookup;"));
					adapter.push(srgName);
					Type args[] = Type.getArgumentTypes(desc);
					adapter.visitFieldInsn(GETSTATIC, "java/lang/Void", "TYPE", "Ljava/lang/Class;");
					adapter.push(args.length);
					adapter.newArray(Type.getType(Class.class));
					for (Type arg : args) {
						adapter.dup();
						adapter.push(arg);
						adapter.arrayStore(Type.getType(Class.class));
					}
					adapter.invokeStatic(Type.getType(MethodType.class), new Method("methodType",
							"(Ljava/lang/Class;[Ljava/lang/Class;)Ljava/lang/invoke/MethodType;"));
					adapter.push(owner);
					adapter.dupX2();
					adapter.invokeVirtual(Type.getType(MethodHandles.Lookup.class), new Method("findSpecial",
							"(Ljava/lang/Class;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/Class;)Ljava/lang/invoke/MethodHandle;"));
					adapter.loadArgs();
					adapter.invokeVirtual(Type.getType(MethodHandle.class), new Method("invoke", proxyMethod.desc));
					break;
				case INVOKEINTERFACE:
					adapter.loadArgs();
					adapter.invokeInterface(owner, targetMethod);
					break;
				default:
					AlchemyRuntimeException.onException(new RuntimeException("Unsupported opcode: " + opcode));
			}
			adapter.returnValue();
			adapter.endMethod();
			break;
		}
	node.methods.remove(oldMethod);
	node.methods.add(newMethod);
	node.accept(writer);
	return writer.toByteArray();
}