Example usage for org.objectweb.asm MethodVisitor visitInsn

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

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Introduction

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

Prototype

public void visitInsn(final int opcode)

Source Link

Document

Visits a zero operand instruction.

Usage

From source file:com.github.fge.grappa.transform.process.GroupClassGenerator.java

License:Apache License

private void generateConstructor(ClassWriter cw) {
    MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, "<init>", CodegenUtils.sig(void.class, String.class), null,
            null);/*from  w  w w .j  a va2  s .c om*/
    mv.visitVarInsn(ALOAD, 0);
    mv.visitVarInsn(ALOAD, 1);
    mv.visitMethodInsn(INVOKESPECIAL, getBaseType().getInternalName(), "<init>",
            CodegenUtils.sig(void.class, String.class), false);
    mv.visitInsn(RETURN);
    mv.visitMaxs(0, 0); // trigger automatic computing
}

From source file:com.github.jasmo.obfuscate.ScrambleStrings.java

License:Open Source License

private void createUnscramble() {
    MethodVisitor mv = unscrambleClass.visitMethod(ACC_PUBLIC | ACC_STATIC, CALL_NAME, CALL_DESC, null, null);
    mv.visitCode();//from   w w w. j ava2  s .  c om
    mv.visitTypeInsn(NEW, "java/lang/String");
    mv.visitInsn(DUP);
    mv.visitMethodInsn(INVOKESTATIC, "java/util/Base64", "getDecoder", "()Ljava/util/Base64$Decoder;", false);
    mv.visitFieldInsn(GETSTATIC, unscrambleClass.name, FIELD_NAME, "[Ljava/lang/String;");
    mv.visitVarInsn(ILOAD, 0);
    mv.visitInsn(AALOAD);
    mv.visitMethodInsn(INVOKEVIRTUAL, "java/util/Base64$Decoder", "decode", "(Ljava/lang/String;)[B", false);
    mv.visitLdcInsn("UTF-8");
    mv.visitMethodInsn(INVOKESPECIAL, "java/lang/String", "<init>", "([BLjava/lang/String;)V", false);
    mv.visitInsn(ARETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

From source file:com.github.javalbert.bytecode.utils.AsmUtils.java

License:Apache License

public static void visitDefaultConstructor(ClassWriter cw, String classTypeDescriptor) {
    MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
    mv.visitCode();// w w w . ja va 2s  .  co  m
    Label l0 = new Label();
    mv.visitLabel(l0);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
    mv.visitInsn(RETURN);
    Label l1 = new Label();
    mv.visitLabel(l1);
    mv.visitLocalVariable("this", classTypeDescriptor, null, l0, l1, 0);
    mv.visitMaxs(1, 1);
    mv.visitEnd();
}

From source file:com.github.javalbert.bytecode.utils.AsmUtils.java

License:Apache License

/**
 * //from  w w w  .j a  v a  2  s  .  c  om
 * @param mv
 * @param i the int value
 */
public static void visitZeroOperandInt(MethodVisitor mv, int i) {
    if (i > 5) {
        mv.visitIntInsn(BIPUSH, i);
    } else {
        int opcode = NOP;
        switch (i) {
        case 0:
            opcode = ICONST_0;
            break;
        case 1:
            opcode = ICONST_1;
            break;
        case 2:
            opcode = ICONST_2;
            break;
        case 3:
            opcode = ICONST_3;
            break;
        case 4:
            opcode = ICONST_4;
            break;
        case 5:
            opcode = ICONST_5;
            break;
        }
        mv.visitInsn(opcode);
    }
}

From source file:com.github.megatronking.stringfog.plugin.StringFogClassVisitor.java

License:Apache License

@Override
public void visitEnd() {
    if (!mIgnoreClass && !isClInitExists && !mStaticFinalFields.isEmpty()) {
        MethodVisitor mv = super.visitMethod(Opcodes.ACC_STATIC, "<clinit>", "()V", null, null);
        mv.visitCode();//w  ww . ja  v a  2 s .c o  m
        // Here init static final fields.
        for (ClassStringField field : mStaticFinalFields) {
            if (!canEncrypted(field.value)) {
                continue;
            }
            String originValue = field.value;
            String encryptValue = mStringFogImpl.encrypt(originValue, mKey);
            mMappingPrinter.output(getJavaClassName(), originValue, encryptValue);
            mv.visitLdcInsn(encryptValue);
            mv.visitMethodInsn(Opcodes.INVOKESTATIC, mFogClassName, "decrypt",
                    "(Ljava/lang/String;)Ljava/lang/String;", false);
            mv.visitFieldInsn(Opcodes.PUTSTATIC, mClassName, field.name, ClassStringField.STRING_DESC);
        }
        mv.visitInsn(Opcodes.RETURN);
        mv.visitMaxs(1, 0);
        mv.visitEnd();
    }
    super.visitEnd();
}

From source file:com.github.rgcjonas.kuemmelgtr.core.Compiler.java

License:Open Source License

public static byte[] compileFunc(TokenSource<RPNToken> source, String variable) throws ParsingError {
    // initialize class
    ClassWriter writer = new ClassWriter(ClassWriter.COMPUTE_FRAMES);

    writer.visit(Opcodes.V1_5, Opcodes.ACC_PUBLIC, "com/github/rgcjonas/kuemmelgtr/jit/BogusName", null,
            CompiledClassBase.class.getName().replace('.', '/'),
            new String[] { Evaluator.Function.class.getName().replace('.', '/') });

    // create constructor
    MethodVisitor construct = writer.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null);
    construct.visitCode();//from   w  w  w  .  ja  va 2 s . com
    construct.visitVarInsn(Opcodes.ALOAD, 0);
    construct.visitMethodInsn(Opcodes.INVOKESPECIAL, CompiledClassBase.class.getName().replace('.', '/'),
            "<init>", "()V");
    construct.visitInsn(Opcodes.RETURN);
    construct.visitMaxs(0, 0);
    construct.visitEnd();

    MethodVisitor method = writer.visitMethod(Opcodes.ACC_PUBLIC, "evaluate", "(D)D", null,
            new String[] { "com/github/rgcjonas/kuemmelgtr/core/RuntimeError" });

    compileCommon(source, method, variable);

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

From source file:com.github.rgcjonas.kuemmelgtr.core.Compiler.java

License:Open Source License

public static byte[] compileBasic(TokenSource<RPNToken> source) throws ParsingError {
    // initialize class
    ClassWriter writer = new ClassWriter(ClassWriter.COMPUTE_FRAMES);

    writer.visit(Opcodes.V1_5, Opcodes.ACC_PUBLIC, "com/github/rgcjonas/kuemmelgtr/jit/BogusName", null,
            CompiledClassBase.class.getName().replace('.', '/'),
            new String[] { Evaluator.Basic.class.getName().replace('.', '/') });

    // create constructor
    MethodVisitor construct = writer.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null);
    construct.visitCode();/*  w  w w.j ava 2 s. co  m*/
    construct.visitVarInsn(Opcodes.ALOAD, 0);
    construct.visitMethodInsn(Opcodes.INVOKESPECIAL, CompiledClassBase.class.getName().replace('.', '/'),
            "<init>", "()V");
    construct.visitInsn(Opcodes.RETURN);
    construct.visitMaxs(0, 0);
    construct.visitEnd();

    MethodVisitor method = writer.visitMethod(Opcodes.ACC_PUBLIC, "evaluate", "()D", null,
            new String[] { "com/github/rgcjonas/kuemmelgtr/core/ParsingError",
                    "com/github/rgcjonas/kuemmelgtr/core/RuntimeError" });

    compileCommon(source, method, null);

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

From source file:com.github.rgcjonas.kuemmelgtr.core.Compiler.java

License:Open Source License

private static void compileCommon(TokenSource<RPNToken> source, MethodVisitor method, String variable)
        throws ParsingError {
    method.visitCode();//from w w w.  j a  v a 2  s .c  o  m

    // we now can compile our token stream
    int currentStackSize = 0; // we keep track of the current stack size to throw errors if we encounter an invalid instruction
    RPNToken t;
    while ((t = source.nextToken()) != null) {
        if (t instanceof RPNToken.Operand) {
            // we push it onto the stack
            method.visitLdcInsn(((RPNToken.Operand) t).getValue());
            currentStackSize++;
        } else if (t instanceof RPNToken.Operator) {
            RPNToken.Operator op = (RPNToken.Operator) t;

            if (currentStackSize < op.getNumOperands())
                throw new ParsingError(t.getSrcLine(), t.getSrcColumn(), "Missing operand(s)");

            switch (op.getName()) {
            case "_add":
                method.visitInsn(Opcodes.DADD);
                currentStackSize--;
                break;
            case "_mult":
                method.visitInsn(Opcodes.DMUL);
                currentStackSize--;
                break;
            case "_sub":
                method.visitInsn(Opcodes.DSUB);
                currentStackSize--;
                break;
            case "_div":
                method.visitInsn(Opcodes.DDIV);
                currentStackSize--;
                break;
            case "_pow":
                method.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Math", "pow", "(DD)D");
                currentStackSize--;
                break;
            default:
                //HACK: support every function in java/lang/Math. Will be way more performant than any lookup-and-evaluate
                //TODO: implement more functions inline
                if (currentStackSize < 1)
                    throw new ParsingError(t.getSrcLine(), t.getSrcColumn(), "Missing operand");
                try {
                    Method meth = Math.class.getDeclaredMethod(op.getName(), double.class); // just check if it's available and hope it returns a double
                    if (meth.getReturnType() != double.class)
                        throw new NoSuchMethodException(); // we don't want to blow up at runtime, do we?

                    method.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Math", op.getName(), "(D)D");
                } catch (NoSuchMethodException e) {
                    // we do not give up. The method may be available at runtime.
                    method.visitVarInsn(Opcodes.ALOAD, 0);
                    method.visitInsn(Opcodes.DUP_X2); // swap the this pointer and double
                    method.visitInsn(Opcodes.POP);
                    method.visitLdcInsn(op.getName());
                    method.visitLdcInsn((int) op.getSrcLine());
                    method.visitLdcInsn((int) op.getSrcColumn());
                    method.visitMethodInsn(Opcodes.INVOKEVIRTUAL,
                            CompiledClassBase.class.getName().replace('.', '/'), "resolveAndEvaluateFunction",
                            "(DLjava/lang/String;II)D");
                }
            }
        } else if (t instanceof RPNToken.VariableRecall) {
            // maybe, maybe the variable is an argument we can load
            if (variable != null && ((RPNToken.VariableRecall) t).getName().equalsIgnoreCase(variable)) {
                method.visitVarInsn(Opcodes.DLOAD, 1);
            } else {
                // we let our parent class do the hard work
                method.visitVarInsn(Opcodes.ALOAD, 0);
                method.visitLdcInsn(((RPNToken.VariableRecall) t).getName());
                method.visitLdcInsn(t.getSrcLine());
                method.visitLdcInsn(t.getSrcColumn());
                method.visitMethodInsn(Opcodes.INVOKEVIRTUAL,
                        CompiledClassBase.class.getName().replace('.', '/'), "getVariable",
                        "(Ljava/lang/String;II)D");
            }
            currentStackSize++;
        } else if (t instanceof RPNToken.VariableAssignment) {
            // also defer to our parent class
            // we do not give up. The method may be available at runtime.
            method.visitVarInsn(Opcodes.ALOAD, 0);
            method.visitInsn(Opcodes.DUP_X2); // swap the this pointer and double
            method.visitInsn(Opcodes.POP);
            method.visitLdcInsn(((RPNToken.VariableAssignment) t).getVariableName());
            method.visitLdcInsn(t.getSrcLine());
            method.visitLdcInsn(t.getSrcColumn());
            method.visitMethodInsn(Opcodes.INVOKEVIRTUAL, CompiledClassBase.class.getName().replace('.', '/'),
                    "setVariable", "(DLjava/lang/String;II)D");
        } else {
            throw new ParsingError(t.getSrcLine(), t.getSrcColumn(), "Unknown instruction: " + t);
        }
    }

    if (currentStackSize != 1)
        throw new ParsingError(0, 0, "Expected stack to be one value, found " + currentStackSize);

    method.visitInsn(Opcodes.DRETURN);

    method.visitMaxs(0, 0);
    method.visitEnd();
}

From source file:com.github.stokito.gag.agent.NoopGenerator.java

License:Apache License

@Override
public MethodVisitor visitMethod(int access, String name, String desc, String sig, String[] exceptions) {

    boolean isNoopForAll = classInfo().getAnnoFor(NOOP_TYPE) != null;
    MethodVisitor mv = writer().visitMethod(access, name, desc, sig, exceptions);
    mv.visitCode();/* w  ww.  java  2s  .c  o m*/

    MethodInfo method = classInfo().getMethod(name, desc);
    boolean isConstructor = "<init>".equals(method.getName());
    boolean isNoopForMethod = method.getAnnoFor(NOOP_TYPE) != null;

    if (!isConstructor && (isNoopForAll || isNoopForMethod)) {
        Type returnType = Type.getReturnType(desc);
        switch (returnType.getSort()) {
        case Type.VOID:
            mv.visitInsn(RETURN);
            break;
        case Type.OBJECT:
        case Type.ARRAY:
            mv.visitInsn(ACONST_NULL);
            mv.visitInsn(ARETURN);
            break;
        case Type.DOUBLE:
            mv.visitInsn(DCONST_0);
            mv.visitInsn(DRETURN);
            break;
        case Type.FLOAT:
            mv.visitInsn(FCONST_0);
            mv.visitInsn(FRETURN);
            break;
        case Type.LONG:
            mv.visitInsn(LCONST_0);
            mv.visitInsn(LRETURN);
            break;
        case Type.INT:
        case Type.SHORT:
        case Type.CHAR:
        case Type.BYTE:
        case Type.BOOLEAN:
            mv.visitInsn(ICONST_0);
            mv.visitInsn(IRETURN);
            break;
        }
        setInstrumented(true);
    }

    mv.visitEnd();
    return mv;
}

From source file:com.github.stokito.gag.agent.RouletteGenerator.java

License:Apache License

@Override
public MethodVisitor visitMethod(int access, String name, String desc, String sig, String[] exceptions) {

    MethodVisitor mv = writer().visitMethod(access, name, desc, sig, exceptions);
    mv.visitCode();/*  w  ww  .  j a  v a 2  s.  c  om*/

    MethodInfo method = classInfo().getMethod(name, desc);
    AnnoInfo anno = method.getAnnoFor(ROULETTE_TYPE);
    if (anno != null) {

        Double probability = (Double) anno.getValue("probability");
        if (probability < 0.0 || probability > 1.0) {
            throw new AnnotationStateError("Probability (" + probability + ") needs to be between 0 and 1");
        }

        Type exception = (Type) anno.getValue("exception");

        // TODO: Figure out how to get the default value from the annotation itself.
        if (exception == null) {
            exception = Type.getType(RuntimeException.class);
        }

        String message = (String) anno.getValue("message");

        Label okay = new Label();

        mv.visitTypeInsn(NEW, "java/util/Random");
        mv.visitInsn(DUP);
        mv.visitMethodInsn(INVOKESPECIAL, "java/util/Random", "<init>", "()V");

        mv.visitMethodInsn(INVOKEVIRTUAL, "java/util/Random", "nextDouble", "()D");
        mv.visitLdcInsn(probability);
        mv.visitInsn(DCMPG);
        mv.visitJumpInsn(IFGT, okay);

        mv.visitTypeInsn(NEW, exception.getInternalName());
        mv.visitInsn(DUP);
        mv.visitLdcInsn(message);
        mv.visitMethodInsn(INVOKESPECIAL, exception.getInternalName(), "<init>", "(Ljava/lang/String;)V");
        mv.visitInsn(ATHROW);

        mv.visitLabel(okay);

        setInstrumented(true);
    }

    mv.visitEnd();
    return mv;
}