Example usage for org.objectweb.asm Opcodes RETURN

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Prototype

int RETURN

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Usage

From source file:cn.annoreg.asm.DelegateGenerator.java

License:Open Source License

public static MethodVisitor generateStaticMethod(ClassVisitor parentClass, MethodVisitor parent,
        String className, String methodName, String desc, final Side side) {

    //This method is a little bit complicated.
    //We need to generate a delegate class implementing NetworkCallDelegate and a redirect
    //the code that originally generated here in parent, into the delegate class,
    //by returning a MethodVisitor under the ClassVisitor of the delegate class.
    //Besides, we should generate a call to NetworkCallManager into parent.

    //Above is the original method. Now it has a little bit change. To allow private call in
    //here, we need to generate the delegate method in this class instead of in a delegate class.
    //We make the delegate method public so that the delegate class can call it.

    //delegateName is a string used by both sides to identify a network-call delegate.
    final String delegateName = className + ":" + methodName + ":" + desc;
    final Type[] args = Type.getArgumentTypes(desc);
    final Type ret = Type.getReturnType(desc);

    //Check types
    for (Type t : args) {
        //TODO support these types
        if (!t.getDescriptor().startsWith("L") && !t.getDescriptor().startsWith("[")) {
            throw new RuntimeException("Unsupported argument type in network call. in method " + methodName
                    + ", " + t.getDescriptor());
        }/*from w w w.  j  a v  a  2  s .c o  m*/
    }
    if (!ret.equals(Type.VOID_TYPE)) {
        throw new RuntimeException(
                "Unsupported return value type in network call. " + "Only void is supported.");
    }

    //Generate call to NetworkCallManager in parent.
    parent.visitCode();
    //First parameter
    parent.visitLdcInsn(delegateName);
    //Second parameter: object array
    pushIntegerConst(parent, args.length); //array size
    parent.visitTypeInsn(Opcodes.ANEWARRAY, Type.getInternalName(Object.class));
    for (int i = 0; i < args.length; ++i) {
        parent.visitInsn(Opcodes.DUP);
        pushIntegerConst(parent, i);
        parent.visitVarInsn(Opcodes.ALOAD, i);
        parent.visitInsn(Opcodes.AASTORE);
    }
    //Call cn.annoreg.mc.network.NetworkCallManager.onNetworkCall
    parent.visitMethodInsn(Opcodes.INVOKESTATIC, Type.getInternalName(NetworkCallManager.class),
            "onNetworkCall",
            Type.getMethodDescriptor(Type.VOID_TYPE, Type.getType(String.class), Type.getType(Object[].class)));
    parent.visitInsn(Opcodes.RETURN);
    parent.visitMaxs(5, args.length);
    parent.visitEnd();

    //Create delegate object.
    final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);
    final String delegateId = Integer.toString(delegateNextID++);
    final Type delegateClassType = Type.getType("cn/annoreg/asm/NetworkCallDelegate_" + delegateId);
    cw.visit(Opcodes.V1_5, Opcodes.ACC_PUBLIC, delegateClassType.getInternalName(), null,
            Type.getInternalName(Object.class),
            new String[] { Type.getInternalName(NetworkCallDelegate.class) });
    //package cn.annoreg.asm;
    //class NetworkCallDelegate_? implements NetworkCallDelegate {
    {
        MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null);
        mv.visitCode();
        mv.visitVarInsn(Opcodes.ALOAD, 0);
        mv.visitMethodInsn(Opcodes.INVOKESPECIAL, Type.getInternalName(Object.class), "<init>", "()V");
        mv.visitInsn(Opcodes.RETURN);
        mv.visitMaxs(1, 1);
        mv.visitEnd();
    }
    //public NetworkCallDelegate_?() {}

    final String delegateFunctionName = methodName + "_delegate_" + delegateId;
    {
        MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "invoke",
                Type.getMethodDescriptor(Type.VOID_TYPE, Type.getType(Object[].class)), null, null);
        mv.visitCode();
        for (int i = 0; i < args.length; ++i) {
            mv.visitVarInsn(Opcodes.ALOAD, 1); //0 is this
            pushIntegerConst(mv, i);
            mv.visitInsn(Opcodes.AALOAD);
            mv.visitTypeInsn(Opcodes.CHECKCAST, args[i].getInternalName());
        }
        mv.visitMethodInsn(Opcodes.INVOKESTATIC,
                //delegateClassType.getInternalName(), //changed to original class
                className.replace('.', '/'), delegateFunctionName, desc);
        mv.visitInsn(Opcodes.RETURN);
        mv.visitMaxs(args.length + 2, 2);
        mv.visitEnd();
    }
    //@Override public void invoke(Object[] args) {
    //    xxxx.xxxx_delegated_xxx((Type0) args[0], (Type1) args[1], ...);
    //}

    //The returned MethodVisitor will visit the original version of the method,
    //including its annotation, where we can get StorageOptions.
    return new MethodVisitor(Opcodes.ASM4, parentClass.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC,
            delegateFunctionName, desc, null, null)) {

        //Remember storage options for each argument
        StorageOption.Option[] options = new StorageOption.Option[args.length];
        int targetIndex = -1;
        StorageOption.Target.RangeOption range = StorageOption.Target.RangeOption.SINGLE;
        double sendRange = -1;

        {
            for (int i = 0; i < options.length; ++i) {
                options[i] = StorageOption.Option.NULL; //set default value
            }
        }

        @Override
        public AnnotationVisitor visitParameterAnnotation(final int parameter, String desc, boolean visible) {
            Type type = Type.getType(desc);
            if (type.equals(Type.getType(StorageOption.Data.class))) {
                options[parameter] = StorageOption.Option.DATA;
            } else if (type.equals(Type.getType(StorageOption.Instance.class))) {
                //INSTANCE as defualt
                options[parameter] = StorageOption.Option.INSTANCE;

                //Change to NULLABLE_INSTANCE if nullable set to true
                return new AnnotationVisitor(this.api,
                        super.visitParameterAnnotation(parameter, desc, visible)) {
                    @Override
                    public void visit(String name, Object value) {
                        if (name.equals("nullable")) {
                            if ((Boolean) value == true) {
                                options[parameter] = StorageOption.Option.NULLABLE_INSTANCE;
                            }
                        }
                        super.visit(name, value);
                    }
                };
            } else if (type.equals(Type.getType(StorageOption.Update.class))) {
                options[parameter] = StorageOption.Option.UPDATE;
            } else if (type.equals(Type.getType(StorageOption.Null.class))) {
                options[parameter] = StorageOption.Option.NULL;
            } else if (type.equals(Type.getType(StorageOption.Target.class))) {
                if (!args[parameter].equals(Type.getType(EntityPlayer.class))) {
                    throw new RuntimeException("Target annotation can only be used on EntityPlayer.");
                }
                if (targetIndex != -1) {
                    throw new RuntimeException("You can not specify multiple targets.");
                }
                options[parameter] = StorageOption.Option.INSTANCE;
                targetIndex = parameter;
                return new AnnotationVisitor(this.api,
                        super.visitParameterAnnotation(parameter, desc, visible)) {
                    @Override
                    public void visitEnum(String name, String desc, String value) {
                        super.visitEnum(name, desc, value);
                        range = StorageOption.Target.RangeOption.valueOf(value);
                    }
                };
            } else if (type.equals(Type.getType(StorageOption.RangedTarget.class))) {
                if (targetIndex != -1) {
                    throw new RuntimeException("You can not specify multiple targets.");
                }
                range = null;
                targetIndex = parameter;
                return new AnnotationVisitor(this.api,
                        super.visitParameterAnnotation(parameter, desc, visible)) {
                    @Override
                    public void visit(String name, Object value) {
                        super.visit(name, value);
                        sendRange = (double) value;
                    }
                };
            }
            return super.visitParameterAnnotation(parameter, desc, visible);
        }

        @Override
        public void visitEnd() {
            super.visitEnd();
            //This is the last method in the delegate class.
            //Finish the class and do the registration.
            cw.visitEnd();
            try {
                Class<?> clazz = classLoader.defineClass(delegateClassType.getClassName(), cw.toByteArray());
                NetworkCallDelegate delegateObj = (NetworkCallDelegate) clazz.newInstance();
                if (side == Side.CLIENT) {
                    NetworkCallManager.registerClientDelegateClass(delegateName, delegateObj, options,
                            targetIndex, range, sendRange);
                } else {
                    NetworkCallManager.registerServerDelegateClass(delegateName, delegateObj, options);
                }
            } catch (Throwable e) {
                throw new RuntimeException("Can not create delegate for network call.", e);
            }
        }
    };
    //public static void delegated(Type0 arg0, Type1, arg1, ...) {
    //    //Code generated by caller.
    //}
    //}
}

From source file:cn.annoreg.asm.DelegateGenerator.java

License:Open Source License

public static MethodVisitor generateNonStaticMethod(ClassVisitor parentClass, MethodVisitor parent,
        String className, String methodName, String desc, final Side side) {

    //convert desc to a non-static method form
    String nonstaticDesc;/* w ww  .ja  va  2  s. c o m*/
    {
        Type staticType = Type.getMethodType(desc);
        Type retType = staticType.getReturnType();
        Type[] argsType = staticType.getArgumentTypes();
        Type[] argsTypeWithThis = new Type[argsType.length + 1];
        argsTypeWithThis[0] = Type.getType('L' + className.replace('.', '/') + ';');
        System.arraycopy(argsType, 0, argsTypeWithThis, 1, argsType.length);
        nonstaticDesc = Type.getMethodDescriptor(retType, argsTypeWithThis);
    }

    //delegateName is a string used by both sides to identify a network-call delegate.
    final String delegateName = className + ":" + methodName + ":" + desc;
    final Type[] args = Type.getArgumentTypes(nonstaticDesc);
    final Type ret = Type.getReturnType(nonstaticDesc);

    //Check types
    for (Type t : args) {
        //TODO support these types
        if (!t.getDescriptor().startsWith("L") && !t.getDescriptor().startsWith("[")) {
            throw new RuntimeException("Unsupported argument type in network call. ");
        }
    }
    if (!ret.equals(Type.VOID_TYPE)) {
        throw new RuntimeException(
                "Unsupported return value type in network call. " + "Only void is supported.");
    }

    //Generate call to NetworkCallManager in parent.
    parent.visitCode();
    //First parameter
    parent.visitLdcInsn(delegateName);
    //Second parameter: object array
    pushIntegerConst(parent, args.length); //this (0) has been included
    parent.visitTypeInsn(Opcodes.ANEWARRAY, "java/lang/Object");
    for (int i = 0; i < args.length; ++i) {
        parent.visitInsn(Opcodes.DUP);
        pushIntegerConst(parent, i);
        parent.visitVarInsn(Opcodes.ALOAD, i);
        parent.visitInsn(Opcodes.AASTORE);
    }
    //Call cn.annoreg.mc.network.NetworkCallManager.onNetworkCall
    parent.visitMethodInsn(Opcodes.INVOKESTATIC, Type.getInternalName(NetworkCallManager.class),
            "onNetworkCall", "(Ljava/lang/String;[Ljava/lang/Object;)V");
    parent.visitInsn(Opcodes.RETURN);
    parent.visitMaxs(5, args.length);
    parent.visitEnd();

    //Create delegate object.
    final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);
    final String delegateId = Integer.toString(delegateNextID++);
    final Type delegateClassType = Type.getType("cn/annoreg/asm/NetworkCallDelegate_" + delegateId);
    cw.visit(Opcodes.V1_5, Opcodes.ACC_PUBLIC, delegateClassType.getInternalName(), null,
            Type.getInternalName(Object.class),
            new String[] { Type.getInternalName(NetworkCallDelegate.class) });
    //package cn.annoreg.asm;
    //class NetworkCallDelegate_? implements NetworkCallDelegate {
    {
        MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null);
        mv.visitCode();
        mv.visitVarInsn(Opcodes.ALOAD, 0);
        mv.visitMethodInsn(Opcodes.INVOKESPECIAL, Type.getInternalName(Object.class), "<init>", "()V");
        mv.visitInsn(Opcodes.RETURN);
        mv.visitMaxs(1, 1);
        mv.visitEnd();
    }
    //public NetworkCallDelegate_?() {}

    final String delegateMethodName = methodName + "_delegate_" + delegateId;
    {
        MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "invoke",
                Type.getMethodDescriptor(Type.VOID_TYPE, Type.getType(Object[].class)), null, null);
        mv.visitCode();

        //check if this is null
        mv.visitVarInsn(Opcodes.ALOAD, 1); //0 is this
        pushIntegerConst(mv, 0);
        mv.visitInsn(Opcodes.AALOAD);
        Label lblEnd = new Label();
        mv.visitJumpInsn(Opcodes.IFNULL, lblEnd);

        for (int i = 0; i < args.length; ++i) {
            mv.visitVarInsn(Opcodes.ALOAD, 1); //0 is this
            pushIntegerConst(mv, i);
            mv.visitInsn(Opcodes.AALOAD);
            mv.visitTypeInsn(Opcodes.CHECKCAST, args[i].getInternalName());
        }
        mv.visitMethodInsn(Opcodes.INVOKESTATIC,
                //delegateClassType.getInternalName(), 
                className.replace('.', '/'), delegateMethodName, nonstaticDesc);

        mv.visitLabel(lblEnd);

        mv.visitInsn(Opcodes.RETURN);
        mv.visitMaxs(args.length + 2, 2);
        mv.visitEnd();
    }
    //@Override public void invoke(Object[] args) {
    //    delegated((Type0) args[0], (Type1) args[1], ...);
    //}

    //The returned MethodVisitor will visit the original version of the method,
    //including its annotation, where we can get StorageOptions.
    return new MethodVisitor(Opcodes.ASM4, parentClass.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC,
            delegateMethodName, nonstaticDesc, null, null)) {

        //Remember storage options for each argument
        StorageOption.Option[] options = new StorageOption.Option[args.length];
        int targetIndex = -1;
        double sendRange = -1;
        StorageOption.Target.RangeOption range = StorageOption.Target.RangeOption.SINGLE;

        {
            for (int i = 0; i < options.length; ++i) {
                options[i] = StorageOption.Option.NULL; //set default value
            }
            options[0] = StorageOption.Option.INSTANCE;
        }

        @Override
        public AnnotationVisitor visitParameterAnnotation(int parameter_in_func, String desc, boolean visible) {
            final int parameter = parameter_in_func + 1; //skip this
            Type type = Type.getType(desc);
            if (type.equals(Type.getType(StorageOption.Data.class))) {
                options[parameter] = StorageOption.Option.DATA;
            } else if (type.equals(Type.getType(StorageOption.Instance.class))) {
                //INSTANCE as defualt
                options[parameter] = StorageOption.Option.INSTANCE;

                //Change to NULLABLE_INSTANCE if nullable set to true
                return new AnnotationVisitor(this.api,
                        super.visitParameterAnnotation(parameter, desc, visible)) {
                    @Override
                    public void visit(String name, Object value) {
                        if (name.equals("nullable")) {
                            if ((Boolean) value == true) {
                                options[parameter] = StorageOption.Option.NULLABLE_INSTANCE;
                            }
                        }
                        super.visit(name, value);
                    }
                };
            } else if (type.equals(Type.getType(StorageOption.Update.class))) {
                options[parameter] = StorageOption.Option.UPDATE;
            } else if (type.equals(Type.getType(StorageOption.Null.class))) {
                options[parameter] = StorageOption.Option.NULL;
            } else if (type.equals(Type.getType(StorageOption.Target.class))) {
                if (!args[parameter].equals(Type.getType(EntityPlayer.class))) {
                    throw new RuntimeException("Target annotation can only be used on EntityPlayer.");
                }
                if (targetIndex != -1) {
                    throw new RuntimeException("You can not specify multiple targets.");
                }
                options[parameter] = StorageOption.Option.INSTANCE;
                targetIndex = parameter;
                return new AnnotationVisitor(this.api,
                        super.visitParameterAnnotation(parameter, desc, visible)) {
                    @Override
                    public void visitEnum(String name, String desc, String value) {
                        super.visitEnum(name, desc, value);
                        range = StorageOption.Target.RangeOption.valueOf(value);
                    }
                };
            } else if (type.equals(Type.getType(StorageOption.RangedTarget.class))) {
                if (targetIndex != -1) {
                    throw new RuntimeException("You can not specify multiple targets.");
                }
                targetIndex = parameter;
                range = null;
                return new AnnotationVisitor(this.api,
                        super.visitParameterAnnotation(parameter, desc, visible)) {
                    @Override
                    public void visit(String name, Object value) {
                        super.visit(name, value);
                        sendRange = (double) value;
                    }
                };
            }
            return super.visitParameterAnnotation(parameter, desc, visible);
        }

        //TODO this option (from annotation)

        @Override
        public void visitEnd() {
            super.visitEnd();
            //This is the last method in the delegate class.
            //Finish the class and do the registration.
            cw.visitEnd();
            try {
                Class<?> clazz = classLoader.defineClass(delegateClassType.getClassName(), cw.toByteArray());
                NetworkCallDelegate delegateObj = (NetworkCallDelegate) clazz.newInstance();
                if (side == Side.CLIENT) {
                    NetworkCallManager.registerClientDelegateClass(delegateName, delegateObj, options,
                            targetIndex, range, sendRange);
                } else {
                    NetworkCallManager.registerServerDelegateClass(delegateName, delegateObj, options);
                }
            } catch (Throwable e) {
                throw new RuntimeException("Can not create delegate for network call.", e);
            }
        }
    };
    //public static void delegated(Type0 arg0, Type1, arg1, ...) {
    //    //Code generated by caller.
    //}
    //}
}

From source file:co.paralleluniverse.fibers.instrument.InstrumentMethod.java

License:Open Source License

private void dumpCodeBlock(MethodVisitor mv, int idx, int skip) {
    int start = codeBlocks[idx].endInstruction;
    int end = codeBlocks[idx + 1].endInstruction;

    for (int i = start + skip; i < end; i++) {
        AbstractInsnNode ins = mn.instructions.get(i);
        switch (ins.getOpcode()) {
        case Opcodes.RETURN:
        case Opcodes.ARETURN:
        case Opcodes.IRETURN:
        case Opcodes.LRETURN:
        case Opcodes.FRETURN:
        case Opcodes.DRETURN:
            emitPopMethod(mv);//from  w  w w .j  a va  2  s .c  o  m
            break;

        case Opcodes.MONITORENTER:
        case Opcodes.MONITOREXIT:
            if (!db.isAllowMonitors()) {
                if (!className.equals("clojure/lang/LazySeq"))
                    throw new UnableToInstrumentException("synchronization", className, mn.name, mn.desc);
            } else if (!warnedAboutMonitors) {
                warnedAboutMonitors = true;
                db.log(LogLevel.WARNING, "Method %s#%s%s contains synchronization", className, mn.name,
                        mn.desc);
            }
            break;

        case Opcodes.INVOKESPECIAL:
            MethodInsnNode min = (MethodInsnNode) ins;
            if ("<init>".equals(min.name)) {
                int argSize = TypeAnalyzer.getNumArguments(min.desc);
                Frame frame = frames[i];
                int stackIndex = frame.getStackSize() - argSize - 1;
                Value thisValue = frame.getStack(stackIndex);
                if (stackIndex >= 1 && isNewValue(thisValue, true)
                        && isNewValue(frame.getStack(stackIndex - 1), false)) {
                    NewValue newValue = (NewValue) thisValue;
                    if (newValue.omitted) {
                        emitNewAndDup(mv, frame, stackIndex, min);
                    }
                } else {
                    db.log(LogLevel.WARNING, "Expected to find a NewValue on stack index %d: %s", stackIndex,
                            frame);
                }
            }
            break;
        }

        ins.accept(mv);
    }
}

From source file:com.alibaba.hotswap.processor.clinit.ClinitModifier.java

License:Open Source License

@Override
public void visitInsn(int opcode) {
    if (opcode == Opcodes.RETURN) {

    }
    super.visitInsn(opcode);
}

From source file:com.alibaba.hotswap.processor.clinit.ClinitVisitor.java

License:Open Source License

@Override
public void visitEnd() {
    // If no clinit method, then add it
    if (!hasClinitMethod) {
        if (!isInterface) {
            int access = Opcodes.ACC_STATIC + Opcodes.ACC_PUBLIC;
            String name = HotswapConstants.HOTSWAP_CLINIT;
            String desc = "()V";
            MethodVisitor mv = super.visitMethod(access, name, desc, null, null);
            if (mv != null) {
                mv.visitCode();//from   ww w .j av  a 2  s  .c  o m
                mv.visitTypeInsn(Opcodes.NEW, "java/util/concurrent/ConcurrentHashMap");
                mv.visitInsn(Opcodes.DUP);
                mv.visitMethodInsn(Opcodes.INVOKESPECIAL, "java/util/concurrent/ConcurrentHashMap", "<init>",
                        "()V");
                mv.visitFieldInsn(Opcodes.PUTSTATIC, className, HotswapConstants.STATIC_FIELD_HOLDER,
                        "Ljava/util/concurrent/ConcurrentHashMap;");

                mv.visitInsn(Opcodes.RETURN);
                mv.visitMaxs(2, 0);
                mv.visitEnd();
            }

            generateClinit();
        } else {
            generateDefaultClinit();
        }
    } else {
        if (!isInterface) {
            generateClinit();
        }
    }

    super.visitEnd();
}

From source file:com.alibaba.hotswap.processor.clinit.ClinitVisitor.java

License:Open Source License

/**
 * Generate <code>&lt;clinit&gt;</code>, call <code>__$$hotswap_clinit$$__</code>
 *///from w w w  .ja  va  2s  . c o  m
private void generateClinit() {
    MethodVisitor clinit = cv.visitMethod(Opcodes.ACC_STATIC, HotswapConstants.CLINIT, "()V", null, null);
    if (clinit != null) {
        clinit.visitCode();

        clinit.visitMethodInsn(Opcodes.INVOKESTATIC, className, HotswapConstants.HOTSWAP_CLINIT, "()V");
        clinit.visitInsn(Opcodes.RETURN);
        clinit.visitMaxs(0, 0);
        clinit.visitEnd();
    }
}

From source file:com.alibaba.hotswap.processor.clinit.ClinitVisitor.java

License:Open Source License

/**
 * Generate <code>&lt;clinit&gt;</code> method with default body
 *///www.j ava 2  s . c  o m
private void generateDefaultClinit() {
    MethodVisitor clinit = cv.visitMethod(Opcodes.ACC_STATIC, HotswapConstants.CLINIT, "()V", null, null);

    if (clinit != null) {
        clinit.visitCode();

        clinit.visitInsn(Opcodes.RETURN);
        clinit.visitMaxs(0, 0);
        clinit.visitEnd();
    }
}

From source file:com.alibaba.hotswap.processor.jdk.classloader.ClassLoaderVisitor.java

License:Open Source License

@Override
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
    MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);

    if (name.equals("checkCerts")) {
        mv.visitCode();/*w  w w.  j  a v  a  2s .  co  m*/
        mv.visitInsn(Opcodes.RETURN);
        mv.visitMaxs(0, 0);
        mv.visitEnd();
        return null;
    }

    if (name.equals("defineClass")
            && desc.equals("(Ljava/lang/String;[BIILjava/security/ProtectionDomain;)Ljava/lang/Class;")) {
        return new DefineClassMethodModifier(mv, access, name, desc);
    }

    return mv;
}

From source file:com.alibaba.hotswap.processor.jdk.reflect.modifier.SetXModifier.java

License:Open Source License

@Override
public void visitCode() {
    super.visitCode();

    loadArg(0);//from w  ww.ja  v  a 2 s  .co  m
    loadThis();
    invokeStatic(Type.getType(FieldReflectHelper.class),
            new Method("isInHotswapFieldHolder", "(Ljava/lang/Object;Ljava/lang/reflect/Field;)Z"));
    Label old = newLabel();
    ifZCmp(EQ, old);

    loadArg(0);
    loadThis();
    loadArg(1);
    box(Type.getArgumentTypes(desc)[1]);

    invokeStatic(Type.getType(FieldReflectHelper.class), new Method("setHotswapFieldHolderValue",
            "(Ljava/lang/Object;Ljava/lang/reflect/Field;Ljava/lang/Object;)V"));

    mv.visitInsn(Opcodes.RETURN);
    mark(old);
}

From source file:com.android.build.gradle.integration.packaging.NativeSoPackagingFromJarTest.java

License:Apache License

/**
 * Creates a class and returns the byte[] with the class
 * @return//from  w  ww . j  a va 2  s. c  om
 */
private static byte[] getDummyClassByteCode() {
    ClassWriter cw = new ClassWriter(0);
    FieldVisitor fv;
    MethodVisitor mv;
    AnnotationVisitor av0;

    cw.visit(Opcodes.V1_6, Opcodes.ACC_PUBLIC + Opcodes.ACC_SUPER, "com/foo/Foo", null, "java/lang/Object",
            null);

    mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null);
    mv.visitCode();
    mv.visitVarInsn(Opcodes.ALOAD, 0);
    mv.visitMethodInsn(Opcodes.INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
    mv.visitInsn(Opcodes.RETURN);
    mv.visitMaxs(1, 1);
    mv.visitEnd();

    mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "aaa", "()V", null, null);
    mv.visitCode();
    mv.visitVarInsn(Opcodes.ALOAD, 0);
    mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "test/Aaa", "bbb", "()V", false);
    mv.visitInsn(Opcodes.RETURN);
    mv.visitMaxs(1, 1);
    mv.visitEnd();

    mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "bbb", "()V", null, null);
    mv.visitCode();
    mv.visitInsn(Opcodes.RETURN);
    mv.visitMaxs(0, 1);
    mv.visitEnd();

    mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "ccc", "()V", null, null);
    mv.visitCode();
    mv.visitInsn(Opcodes.RETURN);
    mv.visitMaxs(0, 1);
    mv.visitEnd();

    cw.visitEnd();

    return cw.toByteArray();
}