Example usage for org.objectweb.asm MethodVisitor visitCode

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

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Introduction

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

Prototype

public void visitCode()

Source Link

Document

Starts the visit of the method's code, if any (i.e.

Usage

From source file:com.github.bmsantos.core.cola.injector.InjectorClassVisitor.java

License:Apache License

private void injectIgnoreMethod(final String feature, final String scenario) {
    final MethodVisitor mv = infoClassVisitor.visitMethod(ACC_PUBLIC,
            String.format(IGNORED_METHOD_NAME_FORMAT, feature, scenario), "()V", null, null);
    mv.visitCode();
    mv.visitVarInsn(ALOAD, 0);//  w  w  w  . ja v a 2s .  co  m
    mv.visitLdcInsn(feature);
    mv.visitLdcInsn(scenario);
    mv.visitMethodInsn(INVOKESTATIC, "com/github/bmsantos/core/cola/story/processor/StoryProcessor", "ignore",
            "(Ljava/lang/String;Ljava/lang/String;)V", false);
    mv.visitInsn(RETURN);
    mv.visitAnnotation("Lorg/junit/Test;", true);
    mv.visitEnd();
    mv.visitMaxs(0, 0);
}

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();
    mv.visitTypeInsn(NEW, "java/lang/String");
    mv.visitInsn(DUP);//from   w  w  w  . j a v  a2  s  .  co m
    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();
    Label l0 = new Label();
    mv.visitLabel(l0);/*  w w w. j av a  2  s  . com*/
    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.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();
        // Here init static final fields.
        for (ClassStringField field : mStaticFinalFields) {
            if (!canEncrypted(field.value)) {
                continue;
            }//from   www.  ja  va2s .  c om
            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();
    construct.visitVarInsn(Opcodes.ALOAD, 0);
    construct.visitMethodInsn(Opcodes.INVOKESPECIAL, CompiledClassBase.class.getName().replace('.', '/'),
            "<init>", "()V");
    construct.visitInsn(Opcodes.RETURN);
    construct.visitMaxs(0, 0);// www.ja  va2  s.  c o  m
    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();
    construct.visitVarInsn(Opcodes.ALOAD, 0);
    construct.visitMethodInsn(Opcodes.INVOKESPECIAL, CompiledClassBase.class.getName().replace('.', '/'),
            "<init>", "()V");
    construct.visitInsn(Opcodes.RETURN);
    construct.visitMaxs(0, 0);/*from w  w w. j a va2 s  .  c o  m*/
    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();

    // 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;/*from w  ww  .ja v a 2 s  . c  o  m*/
    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.AnswerToLifeGenerator.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();

    MethodInfo method = classInfo().getMethod(name, desc);
    for (LocalVarInfo param : method.getLocalVars()) {
        AnnoInfo anno = param.getAnnoFor(ANSWER_TYPE);
        if (anno == null) {
            continue;
        }//  w w  w .j a  v a2s.com

        Type paramType = param.getType();
        switch (paramType.getSort()) {
        case Type.INT:
        case Type.BYTE:
        case Type.CHAR:
        case Type.SHORT:
            mv.visitLdcInsn(FORTY_TWO);
            mv.visitVarInsn(ISTORE, param.getIndex());
            break;
        case Type.LONG:
            mv.visitLdcInsn((long) FORTY_TWO);
            mv.visitVarInsn(LSTORE, param.getIndex());
            break;
        case Type.DOUBLE:
            mv.visitLdcInsn((double) FORTY_TWO);
            mv.visitVarInsn(DSTORE, param.getIndex());
            break;
        case Type.FLOAT:
            mv.visitLdcInsn((float) FORTY_TWO);
            mv.visitVarInsn(FSTORE, param.getIndex());
            break;
        case Type.OBJECT:
            visitObject(mv, param);
            break;
        default:
            throwUnsupportedException(param);
        }

        setInstrumented(true);
    }

    mv.visitEnd();
    return mv;
}

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();

    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);//  w ww.  j  a v a 2 s  .co  m
            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();

    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");
        }//w w  w  .  ja v  a 2s  . c  o m

        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;
}