Java Code Examples for jdk.internal.org.objectweb.asm.MethodVisitor#visitVarInsn()

The following examples show how to use jdk.internal.org.objectweb.asm.MethodVisitor#visitVarInsn() . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.

Example 1

Source File: UnsupportedClassFileVersion.java From openjdk-jdk8u-backup with GNU General Public License v2.0

6 votes

public static void writeClassFile() throws Exception {
    ClassWriter cw = new ClassWriter(0);
    MethodVisitor mv;

    cw.visit(99, ACC_PUBLIC + ACC_SUPER, "ClassFile", null, "java/lang/Object", null);
    mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
    mv.visitCode();
    mv.visitVarInsn(ALOAD, 0);
    mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
    mv.visitInsn(RETURN);
    mv.visitMaxs(1, 1);
    mv.visitEnd();
    cw.visitEnd();

    try (FileOutputStream fos = new FileOutputStream(new File("ClassFile.class"))) {
         fos.write(cw.toByteArray());
    }
}

Example 2

Source File: Proxy.java From totallylazy with Apache License 2.0

6 votes

private static void loadArguments(MethodVisitor mv, Method method) {
    int arguments = method.getParameterCount();
    mv.visitLdcInsn(arguments);
    mv.visitTypeInsn(ANEWARRAY, "java/lang/Object");

    Class<?>[] parameterTypes = method.getParameterTypes();
    for (int i = 0, local = 0; i < parameterTypes.length; i++) {
        Class<?> parameterType = parameterTypes[i];
        local++;
        mv.visitInsn(DUP);
        mv.visitLdcInsn(i);
        mv.visitVarInsn(Asm.load(parameterType), local);
        if (parameterType.isPrimitive() && !parameterType.equals(void.class)) {
            String internalName = Type.getInternalName(Reflection.box(parameterType));
            mv.visitMethodInsn(INVOKESTATIC, internalName, "valueOf", format("(%s)L%s;", Type.getDescriptor(parameterType), internalName), false);
        }
        if (parameterType.equals(double.class) || parameterType.equals(long.class)) local++;
        mv.visitInsn(AASTORE);
    }
}

Example 3

Source File: AddressVarHandleGenerator.java From Bytecoder with Apache License 2.0

6 votes

void addStridesAccessor(BinderClassWriter cw) {
    MethodVisitor mv = cw.visitMethod(ACC_FINAL, "strides", "()[J", null, null);
    mv.visitCode();
    iConstInsn(mv, dimensions);
    mv.visitIntInsn(NEWARRAY, T_LONG);

    for (int i = 0 ; i < dimensions ; i++) {
        mv.visitInsn(DUP);
        iConstInsn(mv, i);
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, implClassName, "dim" + i, "J");
        mv.visitInsn(LASTORE);
    }

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

Example 4

Source File: DefineClassTest.java From openjdk-jdk9 with GNU General Public License v2.0

5 votes

/**
 * Generate a class file with the given class name. The class implements Runnable
 * with a run method to invokestatic the given targetClass/targetMethod.
 */
byte[] generateRunner(String className,
                      String targetClass,
                      String targetMethod) throws Exception {

    ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS
                                     + ClassWriter.COMPUTE_FRAMES);
    cw.visit(V1_9,
            ACC_PUBLIC + ACC_SUPER,
            className.replace(".", "/"),
            null,
            "java/lang/Object",
            new String[] { "java/lang/Runnable" });

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

    // run()
    String tc = targetClass.replace(".", "/");
    mv = cw.visitMethod(ACC_PUBLIC, "run", "()V", null, null);
    mv.visitMethodInsn(INVOKESTATIC, tc, targetMethod, "()V", false);
    mv.visitInsn(RETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();

    cw.visitEnd();
    return cw.toByteArray();
}

Example 5

Source File: EventHandlerProxyCreator.java From TencentKona-8 with GNU General Public License v2.0

5 votes

private static void buildDurationMethod() {
    MethodVisitor mv = classWriter.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, METHOD_DURATION.getName(), METHOD_DURATION.getDescriptor(), null, null);
    mv.visitCode();
    mv.visitVarInsn(Opcodes.LLOAD, 0);
    mv.visitMethodInsn(Opcodes.INVOKESTATIC, Type.getInternalName(EventHandler.class), METHOD_DURATION.getName(), METHOD_DURATION.getDescriptor(), false);
    mv.visitInsn(Opcodes.LRETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

Example 6

Source File: BoundMethodHandle.java From openjdk-8 with GNU General Public License v2.0

5 votes

private static void emitPushFields(String types, String className, MethodVisitor mv) {
    for (int i = 0; i < types.length(); ++i) {
        char tc = types.charAt(i);
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));
    }
}

Example 7

Source File: BoundMethodHandle.java From TencentKona-8 with GNU General Public License v2.0

5 votes

private static void emitPushFields(String types, String className, MethodVisitor mv) {
    for (int i = 0; i < types.length(); ++i) {
        char tc = types.charAt(i);
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));
    }
}

Example 8

Source File: TestPrivateInterfaceMethodReflect.java From jdk8u_jdk with GNU General Public License v2.0

5 votes

private byte[] loadClassData(String name) throws Exception {
    ClassWriter cw = new ClassWriter(0);
    MethodVisitor mv;
    switch (name) {
        case INTERFACE_NAME:
            cw.visit(V1_8, ACC_ABSTRACT | ACC_INTERFACE | ACC_PUBLIC, INTERFACE_NAME, null, "java/lang/Object", null);
            {
                mv = cw.visitMethod(ACC_PRIVATE, "privInstance", "()I", null, null);
                mv.visitCode();
                mv.visitLdcInsn(EXPECTED);
                mv.visitInsn(IRETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
            break;
        case CLASS_NAME:
            cw.visit(52, ACC_SUPER | ACC_PUBLIC, CLASS_NAME, null, "java/lang/Object", new String[]{INTERFACE_NAME});
            {
                mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
                mv.visitCode();
                mv.visitVarInsn(ALOAD, 0);
                mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
                mv.visitInsn(RETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
            break;
        default:
            break;
    }
    cw.visitEnd();

    return cw.toByteArray();
}

Example 9

Source File: TestMultiANewArray.java From openjdk-jdk8u with GNU General Public License v2.0

5 votes

public static void writeClassFile(int cfv) throws Exception {
    ClassWriter cw = new ClassWriter(0);
    MethodVisitor mv;

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

    mv = cw.visitMethod(ACC_PUBLIC + ACC_STATIC, "main", "([Ljava/lang/String;)V", null, null);
    mv.visitCode();
    mv.visitInsn(ICONST_1);
    mv.visitInsn(ICONST_2);
    mv.visitMultiANewArrayInsn("[I", 2);
    mv.visitVarInsn(ASTORE, 1);
    mv.visitInsn(RETURN);
    mv.visitMaxs(2, 2);
    mv.visitEnd();

    cw.visitEnd();

    try (FileOutputStream fos = new FileOutputStream(new File("ClassFile.class"))) {
         fos.write(cw.toByteArray());
    }
}

Example 10

Source File: TestPrivateInterfaceMethodReflect.java From openjdk-jdk8u with GNU General Public License v2.0

5 votes

private byte[] loadClassData(String name) throws Exception {
    ClassWriter cw = new ClassWriter(0);
    MethodVisitor mv;
    switch (name) {
        case INTERFACE_NAME:
            cw.visit(V1_8, ACC_ABSTRACT | ACC_INTERFACE | ACC_PUBLIC, INTERFACE_NAME, null, "java/lang/Object", null);
            {
                mv = cw.visitMethod(ACC_PRIVATE, "privInstance", "()I", null, null);
                mv.visitCode();
                mv.visitLdcInsn(EXPECTED);
                mv.visitInsn(IRETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
            break;
        case CLASS_NAME:
            cw.visit(52, ACC_SUPER | ACC_PUBLIC, CLASS_NAME, null, "java/lang/Object", new String[]{INTERFACE_NAME});
            {
                mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
                mv.visitCode();
                mv.visitVarInsn(ALOAD, 0);
                mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
                mv.visitInsn(RETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
            break;
        default:
            break;
    }
    cw.visitEnd();

    return cw.toByteArray();
}

Example 11

Source File: BoundMethodHandle.java From Java8CN with Apache License 2.0

5 votes

private static void emitPushFields(String types, String className, MethodVisitor mv) {
    for (int i = 0; i < types.length(); ++i) {
        char tc = types.charAt(i);
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));
    }
}

Example 12

Source File: TestPrivateInterfaceMethodReflect.java From openjdk-8-source with GNU General Public License v2.0

5 votes

private byte[] loadClassData(String name) throws Exception {
    ClassWriter cw = new ClassWriter(0);
    MethodVisitor mv;
    switch (name) {
        case INTERFACE_NAME:
            cw.visit(V1_8, ACC_ABSTRACT | ACC_INTERFACE | ACC_PUBLIC, INTERFACE_NAME, null, "java/lang/Object", null);
            {
                mv = cw.visitMethod(ACC_PRIVATE, "privInstance", "()I", null, null);
                mv.visitCode();
                mv.visitLdcInsn(EXPECTED);
                mv.visitInsn(IRETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
            break;
        case CLASS_NAME:
            cw.visit(52, ACC_SUPER | ACC_PUBLIC, CLASS_NAME, null, "java/lang/Object", new String[]{INTERFACE_NAME});
            {
                mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
                mv.visitCode();
                mv.visitVarInsn(ALOAD, 0);
                mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
                mv.visitInsn(RETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
            break;
        default:
            break;
    }
    cw.visitEnd();

    return cw.toByteArray();
}

Example 13

Source File: UnloadClass.java From LearningOfThinkInJava with Apache License 2.0

5 votes

public static void main(String[] args) throws NoSuchMethodException,SecurityException,
        IllegalAccessException,IllegalArgumentException,InvocationTargetException{
    ClassWriter cw=new ClassWriter(ClassWriter.COMPUTE_MAXS|ClassWriter.COMPUTE_FRAMES);
    cw.visit(V1_7,ACC_PUBLIC,"Example",null,"java/lang/Object",null);
    MethodVisitor mw=cw.visitMethod(ACC_PUBLIC,"<init>","()V",null,null);
    mw.visitVarInsn(ALOAD,0);
    mw.visitMethodInsn(INVOKESPECIAL,"java/lang/Object","<init>","()V");
    mw.visitInsn(RETURN);
    mw.visitMaxs(0,0);
    mw.visitEnd();
    mw=cw.visitMethod(ACC_PUBLIC+ACC_STATIC,"main","([Ljava/lang/String;)V",null,null);
    mw.visitFieldInsn(GETSTATIC,"java/lang/System","out","Ljava/io/PrintStream;");
    mw.visitLdcInsn("Hello world!");
    mw.visitMethodInsn(INVOKEVIRTUAL,"java/io/PrintStream","println","(Ljava/lang/String;)V");
    mw.visitInsn(RETURN);
    mw.visitMaxs(0,0);
    mw.visitEnd();
    byte[] code=cw.toByteArray();
    for(int i=0;i<1;i++){
        ClassLoader loader=UnloadClass.class.getClassLoader();
        Method m=ClassLoader.class.getDeclaredMethod("defineClass", String.class, byte[].class, int.class, int.class);
        m.setAccessible(true);
        m.invoke(loader,"Example",code,0,code.length);
        m.setAccessible(false);
        System.gc();
    }

}

Example 14

Source File: MethodHandleImpl.java From openjdk-jdk9 with GNU General Public License v2.0

5 votes

/** Produces byte code for a class that is used as an injected invoker. */
private static byte[] generateInvokerTemplate() {
    ClassWriter cw = new ClassWriter(0);

    // private static class InjectedInvoker {
    //     @Hidden
    //     static Object invoke_V(MethodHandle vamh, Object[] args) throws Throwable {
    //        return vamh.invokeExact(args);
    //     }
    // }
    cw.visit(52, ACC_PRIVATE | ACC_SUPER, "InjectedInvoker", null, "java/lang/Object", null);

    MethodVisitor mv = cw.visitMethod(ACC_STATIC, "invoke_V",
                  "(Ljava/lang/invoke/MethodHandle;[Ljava/lang/Object;)Ljava/lang/Object;",
                  null, null);

    // Suppress invoker method in stack traces.
    AnnotationVisitor av0 = mv.visitAnnotation("Ljava/lang/invoke/LambdaForm$Hidden;", true);
    av0.visitEnd();

    mv.visitCode();
    mv.visitVarInsn(ALOAD, 0);
    mv.visitVarInsn(ALOAD, 1);
    mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/invoke/MethodHandle", "invokeExact",
                       "([Ljava/lang/Object;)Ljava/lang/Object;", false);
    mv.visitInsn(ARETURN);
    mv.visitMaxs(2, 2);
    mv.visitEnd();

    cw.visitEnd();
    return cw.toByteArray();
}

Example 15

Source File: TestConcreteClassWithAbstractMethod.java From openjdk-jdk8u-backup with GNU General Public License v2.0

4 votes

public static byte[] dumpT3() {
    ClassWriter cw = new ClassWriter(0);
    MethodVisitor mv;

    cw.visit(52, ACC_PUBLIC + ACC_SUPER, "p1/T3", null, "p1/T2", null);

    {
        mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
        mv.visitCode();
        mv.visitVarInsn(ALOAD, 0);
        mv.visitMethodInsn(INVOKESPECIAL, "p1/T2", "<init>", "()V", false);
        mv.visitInsn(RETURN);
        mv.visitMaxs(1, 1);
        mv.visitEnd();
    }
    {
        mv = cw.visitMethod(ACC_PUBLIC, "m", "()I", null, null);
        mv.visitCode();
        mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
        mv.visitLdcInsn("p1/T3.m()");
        mv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "print", "(Ljava/lang/String;)V", false);
        mv.visitIntInsn(BIPUSH, 2);
        mv.visitInsn(IRETURN);
        mv.visitMaxs(2, 1);
        mv.visitEnd();
    }
    {
        mv = cw.visitMethod(ACC_PUBLIC + ACC_STATIC, "test", "()I", null, null);
        mv.visitCode();
        mv.visitTypeInsn(NEW, "p1/T3");
        mv.visitInsn(DUP);
        mv.visitMethodInsn(INVOKESPECIAL, "p1/T3", "<init>", "()V", false);
        mv.visitMethodInsn(INVOKEVIRTUAL, "p1/T2", "m", "()I", false);
        mv.visitInsn(IRETURN);
        mv.visitMaxs(3, 2);
        mv.visitEnd();
    }
    cw.visitEnd();

    return cw.toByteArray();
}

Example 16

Source File: VarInsnNode.java From openjdk-jdk8u-backup with GNU General Public License v2.0

4 votes

@Override
public void accept(final MethodVisitor mv) {
    mv.visitVarInsn(opcode, var);
    acceptAnnotations(mv);
}

Example 17

Source File: TestAMEnotNPE.java From TencentKona-8 with GNU General Public License v2.0

4 votes

/**
 * Returns the bytes for a class with name d_name (presumably "D" in some
 * package), extending some class with name sub_what, implementing p.I,
 * and defining two methods m() and m(11args) with access method_acc.
 *
 * @param d_name      Name of class that is defined
 * @param sub_what    Name of class that it extends
 * @param method_acc  Accessibility of method(s) m in defined class.
 * @return
 * @throws Exception
 */
public static byte[] bytesForSomeDsubSomethingSomeAccess
        (String d_name, String sub_what, int method_acc)
        throws Exception {

    ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES
            | ClassWriter.COMPUTE_MAXS);
    MethodVisitor mv;
    String[] interfaces = {"p/I"};

    cw.visit(V1_8, ACC_PUBLIC + ACC_SUPER, d_name, null, sub_what, interfaces);
    {
        mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
        mv.visitCode();
        mv.visitVarInsn(ALOAD, 0);
        mv.visitMethodInsn(INVOKESPECIAL, sub_what, "<init>", "()V");
        mv.visitInsn(RETURN);
        mv.visitMaxs(0, 0);
        mv.visitEnd();
    }
    // int m() {return 3;}
    {
        mv = cw.visitMethod(method_acc, "m", "()I", null, null);
        mv.visitCode();
        mv.visitLdcInsn(new Integer(3));
        mv.visitInsn(IRETURN);
        mv.visitMaxs(0, 0);
        mv.visitEnd();
    }
    // int m(11args) {return 3;}
    {
        mv = cw.visitMethod(method_acc, "m", "(BCSIJ"
                + "Ljava/lang/Object;"
                + "Ljava/lang/Object;"
                + "Ljava/lang/Object;"
                + "Ljava/lang/Object;"
                + "Ljava/lang/Object;"
                + "Ljava/lang/Object;"
                + ")I", null, null);
        mv.visitCode();
        mv.visitLdcInsn(new Integer(3));
        mv.visitInsn(IRETURN);
        mv.visitMaxs(0, 0);
        mv.visitEnd();
    }
    cw.visitEnd();
    return cw.toByteArray();
}

Example 18

Source File: FinalStatic.java From openjdk-jdk8u with GNU General Public License v2.0

4 votes

private byte[] loadClassData(String name) throws Exception {
    ClassWriter cw = new ClassWriter(0);
    MethodVisitor mv;
    switch (name) {
       case CLASS_NAME_A:
            cw.visit(52, ACC_SUPER | ACC_PUBLIC, CLASS_NAME_A, null, "java/lang/Object", null);
            {
                mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
                mv.visitCode();
                mv.visitVarInsn(ALOAD, 0);
                mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
                mv.visitInsn(RETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();

                mv = cw.visitMethod(ACC_FINAL | ACC_STATIC, "m", "()I", null, null);
                mv.visitCode();
                mv.visitLdcInsn(FAILED);
                mv.visitInsn(IRETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
            break;
        case CLASS_NAME_B:
            cw.visit(52, ACC_SUPER | ACC_PUBLIC, CLASS_NAME_B, null, CLASS_NAME_A, null);
            {
                mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
                mv.visitCode();
                mv.visitVarInsn(ALOAD, 0);
                mv.visitMethodInsn(INVOKESPECIAL, CLASS_NAME_A, "<init>", "()V");
                mv.visitInsn(RETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();

                mv = cw.visitMethod(ACC_PUBLIC, "m", "()I", null, null);
                mv.visitCode();
                mv.visitLdcInsn(EXPECTED);
                mv.visitInsn(IRETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();

            }
            break;
        default:
            break;
    }
    cw.visitEnd();

    return cw.toByteArray();
}

Example 19

Source File: VarInsnNode.java From openjdk-8-source with GNU General Public License v2.0

4 votes

@Override
public void accept(final MethodVisitor mv) {
    mv.visitVarInsn(opcode, var);
    acceptAnnotations(mv);
}

Example 20

Source File: VarInsnNode.java From openjdk-jdk8u with GNU General Public License v2.0

4 votes

@Override
public void accept(final MethodVisitor mv) {
    mv.visitVarInsn(opcode, var);
    acceptAnnotations(mv);
}