Example usage for org.objectweb.asm MethodVisitor visitMaxs

List of usage examples for org.objectweb.asm MethodVisitor visitMaxs

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Introduction

In this page you can find the example usage for org.objectweb.asm MethodVisitor visitMaxs.

Prototype

public void visitMaxs(final int maxStack, final int maxLocals)

Source Link

Document

Visits the maximum stack size and the maximum number of local variables of the method.

Usage

From source file:net.wpm.reflectasm.ClassAccess.java

License:Open Source License

static private void insertSetPrimitive(ClassWriter cw, String classNameInternal, List<Field> fields,
        Type primitiveType, String setterMethodName, int loadValueInstruction) {
    int maxStack = 6;
    int maxLocals = 5;
    final String typeNameInternal = primitiveType.getDescriptor();
    MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, setterMethodName,
            "(Ljava/lang/Object;I" + typeNameInternal + ")V", null, null);
    mv.visitCode();//  w ww . j  av  a  2  s  .  c  om
    mv.visitVarInsn(ILOAD, 2);

    if (!fields.isEmpty()) {
        maxStack--;
        Label[] labels = new Label[fields.size()];
        Label labelForInvalidTypes = new Label();
        boolean hasAnyBadTypeLabel = false;
        for (int i = 0, n = labels.length; i < n; i++) {
            if (Type.getType(fields.get(i).getType()).equals(primitiveType))
                labels[i] = new Label();
            else {
                labels[i] = labelForInvalidTypes;
                hasAnyBadTypeLabel = true;
            }
        }
        Label defaultLabel = new Label();
        mv.visitTableSwitchInsn(0, labels.length - 1, defaultLabel, labels);

        for (int i = 0, n = labels.length; i < n; i++) {
            if (!labels[i].equals(labelForInvalidTypes)) {
                Field field = fields.get(i);
                mv.visitLabel(labels[i]);
                mv.visitFrame(F_SAME, 0, null, 0, null);
                if (isStatic(field.getModifiers())) {
                    mv.visitVarInsn(loadValueInstruction, 3);
                    mv.visitFieldInsn(PUTSTATIC, classNameInternal, field.getName(), typeNameInternal);
                } else {
                    mv.visitVarInsn(ALOAD, 1);
                    mv.visitTypeInsn(CHECKCAST, classNameInternal);
                    mv.visitVarInsn(loadValueInstruction, 3);
                    mv.visitFieldInsn(PUTFIELD, classNameInternal, field.getName(), typeNameInternal);
                }
                mv.visitInsn(RETURN);
            }
        }
        // Rest of fields: different type
        if (hasAnyBadTypeLabel) {
            mv.visitLabel(labelForInvalidTypes);
            mv.visitFrame(F_SAME, 0, null, 0, null);
            insertThrowExceptionForFieldType(mv, primitiveType.getClassName());
        }
        // Default: field not found
        mv.visitLabel(defaultLabel);
        mv.visitFrame(F_SAME, 0, null, 0, null);
    }
    mv = insertThrowExceptionForFieldNotFound(mv);
    mv.visitMaxs(maxStack, maxLocals);
    mv.visitEnd();
}

From source file:net.wpm.reflectasm.ClassAccess.java

License:Open Source License

static private void insertGetPrimitive(ClassWriter cw, String classNameInternal, List<Field> fields,
        Type primitiveType, String getterMethodName, int returnValueInstruction) {
    int maxStack = 6;
    final String typeNameInternal = primitiveType.getDescriptor();
    MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, getterMethodName, "(Ljava/lang/Object;I)" + typeNameInternal,
            null, null);/*www.j  ava2  s  .  c o  m*/
    mv.visitCode();
    mv.visitVarInsn(ILOAD, 2);

    if (!fields.isEmpty()) {
        maxStack--;
        Label[] labels = new Label[fields.size()];
        Label labelForInvalidTypes = new Label();
        boolean hasAnyBadTypeLabel = false;
        for (int i = 0, n = labels.length; i < n; i++) {
            if (Type.getType(fields.get(i).getType()).equals(primitiveType))
                labels[i] = new Label();
            else {
                labels[i] = labelForInvalidTypes;
                hasAnyBadTypeLabel = true;
            }
        }
        Label defaultLabel = new Label();
        mv.visitTableSwitchInsn(0, labels.length - 1, defaultLabel, labels);

        for (int i = 0, n = labels.length; i < n; i++) {
            Field field = fields.get(i);
            if (!labels[i].equals(labelForInvalidTypes)) {
                mv.visitLabel(labels[i]);
                mv.visitFrame(F_SAME, 0, null, 0, null);
                if (isStatic(field.getModifiers())) {
                    mv.visitFieldInsn(GETSTATIC, classNameInternal, field.getName(), typeNameInternal);
                } else {
                    mv.visitVarInsn(ALOAD, 1);
                    mv.visitTypeInsn(CHECKCAST, classNameInternal);
                    mv.visitFieldInsn(GETFIELD, classNameInternal, field.getName(), typeNameInternal);
                }
                mv.visitInsn(returnValueInstruction);
            }
        }
        // Rest of fields: different type
        if (hasAnyBadTypeLabel) {
            mv.visitLabel(labelForInvalidTypes);
            mv.visitFrame(F_SAME, 0, null, 0, null);
            insertThrowExceptionForFieldType(mv, primitiveType.getClassName());
        }
        // Default: field not found
        mv.visitLabel(defaultLabel);
        mv.visitFrame(F_SAME, 0, null, 0, null);
    }
    mv = insertThrowExceptionForFieldNotFound(mv);
    mv.visitMaxs(maxStack, 3);
    mv.visitEnd();

}

From source file:net.yrom.tools.WriteStyleablesProcessor.java

License:Apache License

private void writeClinit(ClassWriter writer) {
    Map<String, int[]> styleables = symbols.getStyleables();
    MethodVisitor clinit = writer.visitMethod(Opcodes.ACC_STATIC, "<clinit>", "()V", null, null);
    clinit.visitCode();/*from   w  w  w  .j  a  v  a  2  s .  c  om*/

    for (Map.Entry<String, int[]> entry : styleables.entrySet()) {
        final String field = entry.getKey();
        final int[] value = entry.getValue();
        final int length = value.length;
        pushInt(clinit, length);
        clinit.visitIntInsn(Opcodes.NEWARRAY, Opcodes.T_INT);
        for (int i = 0; i < length; i++) {
            clinit.visitInsn(Opcodes.DUP); // dup
            pushInt(clinit, i);
            pushInt(clinit, value[i]);
            clinit.visitInsn(Opcodes.IASTORE); // iastore
        }
        clinit.visitFieldInsn(Opcodes.PUTSTATIC, RSymbols.R_STYLEABLES_CLASS_NAME, field, "[I");
    }
    clinit.visitInsn(Opcodes.RETURN);
    clinit.visitMaxs(0, 0); // auto compute
    clinit.visitEnd();
}

From source file:nova.core.wrapper.mc.forge.v17.asm.lib.ComponentInjector.java

License:Open Source License

private Class<? extends T> construct(List<Class<? extends Component>> components) {

    // Map components to specified wrapped interfaces
    Map<Class<?>, Class<? extends Component>> intfComponentMap = new HashMap<>();
    for (Class<? extends Component> component : components) {
        for (Passthrough pt : component.getAnnotationsByType(Passthrough.class)) {
            Class<?> intf;//www .  ja  v a  2  s.c o  m
            try {
                intf = Class.forName(pt.value());
            } catch (ClassNotFoundException exec) {
                throw new ClassLoaderUtil.ClassLoaderException(
                        "Invalid passthrough \"%s\" on component %s, the specified interface doesn't exist.",
                        pt.value(), component);
            }
            if (!intf.isAssignableFrom(component)) {
                throw new ClassLoaderUtil.ClassLoaderException(
                        "Invalid passthrough \"%s\" on component %s, the specified interface isn't implemented.",
                        pt.value(), component);
            }
            if (intfComponentMap.containsKey(intf)) {
                throw new ClassLoaderUtil.ClassLoaderException(
                        "Duplicate Passthrough interface found: %s (%s, %s)", pt.value(), component,
                        intfComponentMap.get(intf));
            }
            intfComponentMap.put(intf, component);
        }
    }

    // Create new ClassNode from cached bytes
    ClassNode clazzNode = new ClassNode();
    String name = Type.getInternalName(baseClazz);
    String classname = name + "_$$_NOVA_" + cache.size();

    // Inject block field
    clazzNode.visit(V1_8, ACC_PUBLIC | ACC_SUPER, classname, null, name,
            intfComponentMap.keySet().stream().map(Type::getInternalName).toArray(s -> new String[s]));
    clazzNode.visitField(ACC_PRIVATE | ACC_FINAL, "$$_provider", Type.getDescriptor(ComponentProvider.class),
            null, null).visitEnd();

    // Add constructors
    for (Constructor<?> constructor : baseClazz.getConstructors()) {
        int mod = constructor.getModifiers();
        String descr = Type.getConstructorDescriptor(constructor);

        if (Modifier.isFinal(mod) || Modifier.isPrivate(mod)) {
            continue;
        }
        MethodVisitor mv = clazzNode.visitMethod(mod, "<init>", descr, null,
                ASMHelper.getExceptionTypes(constructor));

        // Call super constructor
        mv.visitCode();
        // load this
        mv.visitVarInsn(ALOAD, 0);
        Class<?>[] parameters = constructor.getParameterTypes();
        for (int i = 0; i < constructor.getParameterCount(); i++) {
            // variables
            mv.visitVarInsn(Type.getType(parameters[i]).getOpcode(ILOAD), i + 1);
        }
        mv.visitMethodInsn(INVOKESPECIAL, Type.getInternalName(baseClazz), "<init>", descr, false);
        // return
        mv.visitInsn(RETURN);
        mv.visitMaxs(0, 0);
        mv.visitEnd();
    }

    // Add methods
    for (Class<?> intf : intfComponentMap.keySet()) {
        // Create class constant
        Type clazzConst = Type.getType(intf.getClass());

        for (Method m : intf.getMethods()) {
            boolean isVoid = m.getReturnType() == null;
            String descr = Type.getMethodDescriptor(m);

            MethodVisitor mv = clazzNode.visitMethod(ACC_PUBLIC, m.getName(), descr, null,
                    ASMHelper.getExceptionTypes(m));
            mv.visitCode();

            // load block instance
            mv.visitVarInsn(ALOAD, 0);
            mv.visitFieldInsn(GETFIELD, classname, "$$_provider", Type.getDescriptor(ComponentProvider.class));
            mv.visitLdcInsn(clazzConst);
            // load component instance
            mv.visitMethodInsn(INVOKEVIRTUAL, Type.getInternalName(ComponentProvider.class), "get",
                    Type.getMethodDescriptor(Type.getType(Component.class), Type.getType(Class.class)), false);

            // add parameters
            Class<?>[] parameters = m.getParameterTypes();
            for (int i = 0; i < m.getParameterCount(); i++) {
                mv.visitVarInsn(Type.getType(parameters[i]).getOpcode(ILOAD), i + 1);
            }

            // invoke
            mv.visitMethodInsn(INVOKEINTERFACE, Type.getInternalName(intf), m.getName(), descr, true);
            mv.visitInsn(isVoid ? RETURN : Type.getType(m.getReturnType()).getOpcode(IRETURN));
            mv.visitMaxs(0, 0);
            mv.visitEnd();
        }
    }

    clazzNode.visitEnd();

    return ASMHelper.defineClass(clazzNode, ClassWriter.COMPUTE_MAXS, baseClazz.getProtectionDomain());
}

From source file:one.nio.http.gen.RequestHandlerGenerator.java

License:Apache License

public RequestHandler generateFor(Method m, Object router) {
    if (Modifier.isStatic(m.getModifiers())) {
        throw new IllegalArgumentException("Method should not be static: " + m);
    }// w w w. jav a 2s  .co m

    Class returnType = m.getReturnType();
    if (returnType != void.class && returnType != Response.class) {
        throw new IllegalArgumentException("Invalid return type of " + m);
    }

    String className = "RequestHandler" + (count++) + "_" + m.getName();
    String routerType = Type.getDescriptor(m.getDeclaringClass());

    ClassWriter cv = new ClassWriter(ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES);
    cv.visit(V1_6, ACC_PUBLIC | ACC_FINAL, className, null, "java/lang/Object",
            new String[] { "one/nio/http/RequestHandler" });

    // private final Object router;
    cv.visitField(ACC_PRIVATE | ACC_FINAL, "router", routerType, null, null).visitEnd();

    // public RequestHandler(Object router);
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC, "<init>", "(" + routerType + ")V", null, null);
    mv.visitCode();

    mv.visitVarInsn(ALOAD, 0);
    mv.visitInsn(DUP);
    mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
    mv.visitVarInsn(ALOAD, 1);
    mv.visitFieldInsn(PUTFIELD, className, "router", routerType);

    mv.visitInsn(RETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();

    // public final void handleRequest(Request request, HttpSession session) throws IOException;
    mv = cv.visitMethod(ACC_PUBLIC | ACC_FINAL, "handleRequest",
            "(Lone/nio/http/Request;Lone/nio/http/HttpSession;)V", null, null);
    mv.visitCode();

    if (m.getReturnType() == Response.class) {
        mv.visitVarInsn(ALOAD, 2);
    }

    mv.visitVarInsn(ALOAD, 0);
    mv.visitFieldInsn(GETFIELD, className, "router", routerType);
    setupArguments(mv, m);
    emitInvoke(mv, m);

    if (m.getReturnType() == Response.class) {
        mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/http/HttpSession", "writeResponse",
                "(Lone/nio/http/Response;)V");
    }

    mv.visitInsn(RETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();

    cv.visitEnd();
    return instantiate(cv.toByteArray(), m, router);
}

From source file:one.nio.serial.gen.DelegateGenerator.java

License:Apache License

private static void generateConstructor(ClassVisitor cv) {
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
    mv.visitCode();//from   www .  j av a2  s. co  m

    mv.visitVarInsn(ALOAD, 0);
    mv.visitMethodInsn(INVOKESPECIAL, MAGIC_CLASS, "<init>", "()V");

    mv.visitInsn(RETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

From source file:one.nio.serial.gen.DelegateGenerator.java

License:Apache License

private static void generateCalcSize(ClassVisitor cv, Class cls, FieldDescriptor[] fds) {
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC | ACC_FINAL, "calcSize",
            "(Ljava/lang/Object;Lone/nio/serial/CalcSizeStream;)V", null,
            new String[] { "java/io/IOException" });
    mv.visitCode();//from w w w.j  a va 2  s  .c  o m

    Method writeObjectMethod = JavaInternals.findMethodRecursively(cls, "writeObject",
            ObjectOutputStream.class);
    if (writeObjectMethod != null
            && !Repository.hasOptions(writeObjectMethod.getDeclaringClass(), Repository.SKIP_WRITE_OBJECT)) {
        mv.visitVarInsn(ALOAD, 1);
        mv.visitFieldInsn(GETSTATIC, "one/nio/serial/gen/NullObjectOutputStream", "INSTANCE",
                "Lone/nio/serial/gen/NullObjectOutputStream;");
        emitInvoke(mv, writeObjectMethod);
    }

    int primitiveFieldsSize = 0;

    for (FieldDescriptor fd : fds) {
        Field ownField = fd.ownField();
        Class sourceClass = fd.type().resolve();
        FieldType srcType = FieldType.valueOf(sourceClass);

        if (srcType != FieldType.Object) {
            primitiveFieldsSize += srcType.dataSize;
        } else if (ownField == null) {
            primitiveFieldsSize++; // 1 byte to encode null reference
        } else {
            mv.visitVarInsn(ALOAD, 2);
            mv.visitVarInsn(ALOAD, 1);
            if (fd.parentField() != null)
                emitGetField(mv, fd.parentField());
            emitGetField(mv, ownField);
            emitTypeCast(mv, ownField.getType(), sourceClass);
            mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/serial/CalcSizeStream", "writeObject",
                    "(Ljava/lang/Object;)V");
        }
    }

    if (primitiveFieldsSize != 0) {
        mv.visitVarInsn(ALOAD, 2);
        mv.visitInsn(DUP);
        mv.visitFieldInsn(GETFIELD, "one/nio/serial/CalcSizeStream", "count", "I");
        emitInt(mv, primitiveFieldsSize);
        mv.visitInsn(IADD);
        mv.visitFieldInsn(PUTFIELD, "one/nio/serial/CalcSizeStream", "count", "I");
    }

    mv.visitInsn(RETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

From source file:one.nio.serial.gen.DelegateGenerator.java

License:Apache License

private static void generateWrite(ClassVisitor cv, Class cls, FieldDescriptor[] fds) {
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC | ACC_FINAL, "write",
            "(Ljava/lang/Object;Lone/nio/serial/DataStream;)V", null, new String[] { "java/io/IOException" });
    mv.visitCode();/*from  w  w w  .  j a v a2  s.  co m*/

    Method writeObjectMethod = JavaInternals.findMethodRecursively(cls, "writeObject",
            ObjectOutputStream.class);
    if (writeObjectMethod != null
            && !Repository.hasOptions(writeObjectMethod.getDeclaringClass(), Repository.SKIP_WRITE_OBJECT)) {
        mv.visitVarInsn(ALOAD, 1);
        mv.visitFieldInsn(GETSTATIC, "one/nio/serial/gen/NullObjectOutputStream", "INSTANCE",
                "Lone/nio/serial/gen/NullObjectOutputStream;");
        emitInvoke(mv, writeObjectMethod);
    }

    for (FieldDescriptor fd : fds) {
        Field ownField = fd.ownField();
        Class sourceClass = fd.type().resolve();
        FieldType srcType = FieldType.valueOf(sourceClass);

        mv.visitVarInsn(ALOAD, 2);

        if (ownField == null) {
            mv.visitInsn(FieldType.Void.convertTo(srcType));
        } else {
            mv.visitVarInsn(ALOAD, 1);
            if (fd.parentField() != null)
                emitGetField(mv, fd.parentField());
            emitGetField(mv, ownField);
            emitTypeCast(mv, ownField.getType(), sourceClass);
        }

        mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/serial/DataStream", srcType.writeMethod(),
                srcType.writeSignature());
    }

    mv.visitInsn(RETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

From source file:one.nio.serial.gen.DelegateGenerator.java

License:Apache License

private static void generateRead(ClassVisitor cv, Class cls, FieldDescriptor[] fds, List<Field> defaultFields) {
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC | ACC_FINAL, "read",
            "(Lone/nio/serial/DataStream;)Ljava/lang/Object;", null,
            new String[] { "java/io/IOException", "java/lang/ClassNotFoundException" });
    mv.visitCode();//from   w  w  w. j  a v a  2s.c om

    mv.visitVarInsn(ALOAD, 1);
    mv.visitTypeInsn(NEW, Type.getInternalName(cls));
    mv.visitInsn(DUP);
    mv.visitVarInsn(ASTORE, 2);
    mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/serial/DataStream", "register", "(Ljava/lang/Object;)V");

    ArrayList<Field> parents = new ArrayList<Field>(1);
    for (FieldDescriptor fd : fds) {
        Field ownField = fd.ownField();
        Field parentField = fd.parentField();
        Class sourceClass = fd.type().resolve();
        FieldType srcType = FieldType.valueOf(sourceClass);

        if (parentField != null && !parents.contains(parentField)) {
            parents.add(parentField);
            mv.visitFieldInsn(GETSTATIC, "one/nio/util/JavaInternals", "unsafe", "Lsun/misc/Unsafe;");
            mv.visitVarInsn(ALOAD, 2);
            mv.visitLdcInsn(unsafe.objectFieldOffset(parentField));
            mv.visitTypeInsn(NEW, Type.getInternalName(parentField.getType()));
            mv.visitMethodInsn(INVOKESPECIAL, "sun/misc/Unsafe", "putObject",
                    "(Ljava/lang/Object;JLjava/lang/Object;)V");
        }

        if (ownField == null) {
            mv.visitVarInsn(ALOAD, 1);
            mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/serial/DataStream", srcType.readMethod(),
                    srcType.readSignature());
            mv.visitInsn(srcType.convertTo(FieldType.Void));
        } else if (Modifier.isFinal(ownField.getModifiers())) {
            FieldType dstType = FieldType.valueOf(ownField.getType());
            mv.visitFieldInsn(GETSTATIC, "one/nio/util/JavaInternals", "unsafe", "Lsun/misc/Unsafe;");
            mv.visitVarInsn(ALOAD, 2);
            if (parentField != null)
                emitGetField(mv, parentField);
            mv.visitLdcInsn(unsafe.objectFieldOffset(ownField));
            mv.visitVarInsn(ALOAD, 1);
            mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/serial/DataStream", srcType.readMethod(),
                    srcType.readSignature());
            if (srcType == FieldType.Object)
                emitTypeCast(mv, Object.class, sourceClass);
            emitTypeCast(mv, sourceClass, ownField.getType());
            mv.visitMethodInsn(INVOKESPECIAL, "sun/misc/Unsafe", dstType.putMethod(), dstType.putSignature());
        } else {
            mv.visitVarInsn(ALOAD, 2);
            if (parentField != null)
                emitGetField(mv, parentField);
            mv.visitVarInsn(ALOAD, 1);
            mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/serial/DataStream", srcType.readMethod(),
                    srcType.readSignature());
            if (srcType == FieldType.Object)
                emitTypeCast(mv, Object.class, sourceClass);
            emitTypeCast(mv, sourceClass, ownField.getType());
            emitPutField(mv, ownField);
        }
    }

    if (defaultFields != null && !defaultFields.isEmpty()) {
        for (Field defaultField : defaultFields) {
            String defaultValue = defaultField.getAnnotation(Default.class).value();
            putFieldConstant(mv, defaultField, defaultValue);
        }
    }

    Method readObjectMethod = JavaInternals.findMethodRecursively(cls, "readObject", ObjectInputStream.class);
    if (readObjectMethod != null
            && !Repository.hasOptions(readObjectMethod.getDeclaringClass(), Repository.SKIP_READ_OBJECT)) {
        mv.visitVarInsn(ALOAD, 2);
        mv.visitFieldInsn(GETSTATIC, "one/nio/serial/gen/NullObjectInputStream", "INSTANCE",
                "Lone/nio/serial/gen/NullObjectInputStream;");
        emitInvoke(mv, readObjectMethod);
    }

    mv.visitVarInsn(ALOAD, 2);
    mv.visitInsn(ARETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

From source file:one.nio.serial.gen.DelegateGenerator.java

License:Apache License

private static void generateSkip(ClassVisitor cv, FieldDescriptor[] fds) {
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC | ACC_FINAL, "skip", "(Lone/nio/serial/DataStream;)V", null,
            new String[] { "java/io/IOException", "java/lang/ClassNotFoundException" });
    mv.visitCode();/*  w  ww  .ja v  a 2s  . co m*/

    int skipSize = 0;

    for (FieldDescriptor fd : fds) {
        Class sourceClass = fd.type().resolve();
        FieldType srcType = FieldType.valueOf(sourceClass);

        if (srcType != FieldType.Object) {
            skipSize += srcType.dataSize;
        } else {
            if (skipSize > 0) {
                mv.visitVarInsn(ALOAD, 1);
                emitInt(mv, skipSize);
                mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/serial/DataStream", "skipBytes", "(I)I");
                mv.visitInsn(POP);
                skipSize = 0;
            }
            mv.visitVarInsn(ALOAD, 1);
            mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/serial/DataStream", "readObject",
                    "()Ljava/lang/Object;");
            mv.visitInsn(POP);
        }
    }

    if (skipSize > 0) {
        mv.visitVarInsn(ALOAD, 1);
        emitInt(mv, skipSize);
        mv.visitMethodInsn(INVOKEVIRTUAL, "one/nio/serial/DataStream", "skipBytes", "(I)I");
        mv.visitInsn(POP);
    }

    mv.visitInsn(RETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}