org.objectweb.asm.commons.Method#getName ( )源码实例Demo

public void addSupportMethod() {
        int access = Opcodes.ACC_PUBLIC;
        Method m = new Method("isSupport", "(I)Z");
        MethodVisitor mv = super.visitMethod(access,
                m.getName(),
                m.getDescriptor(),
                null, null);

        mv.visitCode();
        mv.visitVarInsn(Opcodes.ALOAD, 1);
//        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "hashCode", "()I", false);

        int[] hashArray = new int[fixMtds.size()];
        Label[] labelArray = new Label[fixMtds.size()];
        Label l0 = new Label();
        Label l1 = new Label();
        for (int i = 0; i < fixMtds.size(); i++) {
            hashArray[i] = AcesoProguardMap.instance().getClassData(visitedClassName).getMtdIndex(fixMtds.get(i));
            labelArray[i] = l0;
        }

        mv.visitLookupSwitchInsn(l1, hashArray, labelArray);
        mv.visitLabel(l0);
        mv.visitFrame(Opcodes.F_SAME, 0, null, 0, null);
        mv.visitInsn(Opcodes.ICONST_1);
        mv.visitInsn(Opcodes.IRETURN);
        mv.visitLabel(l1);
        mv.visitFrame(Opcodes.F_SAME, 0, null, 0, null);
        mv.visitInsn(Opcodes.ICONST_0);
        mv.visitInsn(Opcodes.IRETURN);
        mv.visitMaxs(1, 2);
        mv.visitEnd();

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

    }
 

private @Nullable Method hack(@Nullable Method method) {
    if (method == null) {
        return null;
    }
    Type[] argumentTypes = method.getArgumentTypes();
    Type[] hackedArgumentTypes = new Type[argumentTypes.length];
    for (int i = 0; i < argumentTypes.length; i++) {
        hackedArgumentTypes[i] = hack(argumentTypes[i]);
    }
    return new Method(method.getName(), hack(method.getReturnType()), hackedArgumentTypes);
}
 

/***
 * Inserts a trampoline to this class so that the updated methods can make calls to super
 * class methods.
 * <p/>
 * Pseudo code for this trampoline:
 * <code>
 * Object access$super($classType instance, String name, object[] args) {
 * switch(name) {
 * case "firstMethod.(Ljava/lang/String;Ljava/lang/Object;)Ljava/lang/Object;":
 * return super~instance.firstMethod((String)arg[0], arg[1]);
 * case "secondMethod.(Ljava/lang/String;I)V":
 * return super~instance.firstMethod((String)arg[0], arg[1]);
 * <p>
 * default:
 * StringBuilder $local1 = new StringBuilder();
 * $local1.append("Method not found ");
 * $local1.append(name);
 * $local1.append(" in " $classType $super implementation");
 * throw new $package/InstantReloadException($local1.toString());
 * }
 * </code>
 */
private void createAccessSuper() {
    int access = Opcodes.ACC_STATIC | Opcodes.ACC_PUBLIC
            | Opcodes.ACC_SYNTHETIC | Opcodes.ACC_VARARGS;
    Method m = new Method("access$super", "(L" + visitedClassName
            + ";Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/Object;");
    MethodVisitor visitor = super.visitMethod(access,
            m.getName(),
            m.getDescriptor(),
            null, null);

    final GeneratorAdapter mv = new GeneratorAdapter(access, m, visitor);

    // Gather all methods from itself and its superclasses to generate a giant access$super
    // implementation.
    // This will work fine as long as we don't support adding methods to a class.
    final Map<String, MethodReference> uniqueMethods =
            new HashMap<String, MethodReference>();
    if (parentNodes.isEmpty()) {
        // if we cannot determine the parents for this class, let's blindly add all the
        // method of the current class as a gateway to a possible parent version.
        addAllNewMethods(uniqueMethods, classNode);
    } else {
        // otherwise, use the parent list.
        for (ClassNode parentNode : parentNodes) {
            addAllNewMethods(uniqueMethods, parentNode);
        }
    }

    new StringSwitch() {
        @Override
        void visitString() {
            mv.visitVarInsn(Opcodes.ALOAD, 1);
        }

        @Override
        void visitCase(String methodName) {
            MethodReference methodRef = uniqueMethods.get(methodName);

            mv.visitVarInsn(Opcodes.ALOAD, 0);

            Type[] args = Type.getArgumentTypes(methodRef.method.desc);
            int argc = 0;
            for (Type t : args) {
                mv.visitVarInsn(Opcodes.ALOAD, 2);
                mv.push(argc);
                mv.visitInsn(Opcodes.AALOAD);
                ByteCodeUtils.unbox(mv, t);
                argc++;
            }

            if (TRACING_ENABLED) {
                trace(mv, "super selected ", methodRef.owner.name,
                        methodRef.method.name, methodRef.method.desc);
            }
            // Call super on the other object, yup this works cos we are on the right place to
            // call from.
            mv.visitMethodInsn(Opcodes.INVOKESPECIAL,
                    methodRef.owner.name,
                    methodRef.method.name,
                    methodRef.method.desc, false);

            Type ret = Type.getReturnType(methodRef.method.desc);
            if (ret.getSort() == Type.VOID) {
                mv.visitInsn(Opcodes.ACONST_NULL);
            } else {
                mv.box(ret);
            }
            mv.visitInsn(Opcodes.ARETURN);
        }

        @Override
        void visitDefault() {
            writeMissingMessageWithHash(mv, visitedClassName);
        }
    }.visit(mv, uniqueMethods.keySet());

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

/***
 * Inserts a trampoline to this class so that the updated methods can make calls to
 * constructors.
 * <p>
 * <p/>
 * Pseudo code for this trampoline:
 * <code>
 * ClassName(Object[] args, Marker unused) {
 * String name = (String) args[0];
 * if (name.equals(
 * "java/lang/ClassName.(Ljava/lang/String;Ljava/lang/Object;)Ljava/lang/Object;")) {
 * this((String)arg[1], arg[2]);
 * return
 * }
 * if (name.equals("SuperClassName.(Ljava/lang/String;I)V")) {
 * super((String)arg[1], (int)arg[2]);
 * return;
 * }
 * ...
 * StringBuilder $local1 = new StringBuilder();
 * $local1.append("Method not found ");
 * $local1.append(name);
 * $local1.append(" in " $classType $super implementation");
 * throw new $package/InstantReloadException($local1.toString());
 * }
 * </code>
 */
private void createDispatchingThis() {
    // Gather all methods from itself and its superclasses to generate a giant constructor
    // implementation.
    // This will work fine as long as we don't support adding constructors to classes.
    final Map<String, MethodNode> uniqueMethods = new HashMap<String, MethodNode>();

    addAllNewConstructors(uniqueMethods, classNode, true /*keepPrivateConstructors*/);
    for (ClassNode parentNode : parentNodes) {
        addAllNewConstructors(uniqueMethods, parentNode, false /*keepPrivateConstructors*/);
    }

    int access = Opcodes.ACC_PUBLIC | Opcodes.ACC_SYNTHETIC;

    Method m = new Method(AsmUtils.CONSTRUCTOR,
            ConstructorArgsRedirection.DISPATCHING_THIS_SIGNATURE);
    MethodVisitor visitor = super.visitMethod(0, m.getName(), m.getDescriptor(), null, null);
    final GeneratorAdapter mv = new GeneratorAdapter(access, m, visitor);

    mv.visitCode();
    // Mark this code as redirection code
    Label label = new Label();
    mv.visitLineNumber(0, label);

    // Get and store the constructor canonical name.
    mv.visitVarInsn(Opcodes.ALOAD, 1);
    mv.push(0);
    mv.visitInsn(Opcodes.AALOAD);
    mv.unbox(Type.getType("Ljava/lang/String;"));
    final int constructorCanonicalName = mv.newLocal(Type.getType("Ljava/lang/String;"));
    mv.storeLocal(constructorCanonicalName);

    new StringSwitch() {

        @Override
        void visitString() {
            mv.loadLocal(constructorCanonicalName);
        }

        @Override
        void visitCase(String canonicalName) {
            MethodNode methodNode = uniqueMethods.get(canonicalName);
            String owner = canonicalName.split("\\.")[0];

            // Parse method arguments and
            mv.visitVarInsn(Opcodes.ALOAD, 0);
            Type[] args = Type.getArgumentTypes(methodNode.desc);
            int argc = 0;
            for (Type t : args) {
                mv.visitVarInsn(Opcodes.ALOAD, 1);
                mv.push(argc + 1);
                mv.visitInsn(Opcodes.AALOAD);
                ByteCodeUtils.unbox(mv, t);
                argc++;
            }

            mv.visitMethodInsn(Opcodes.INVOKESPECIAL, owner, AsmUtils.CONSTRUCTOR,
                    methodNode.desc, false);

            mv.visitInsn(Opcodes.RETURN);
        }

        @Override
        void visitDefault() {
            writeMissingMessageWithHash(mv, visitedClassName);
        }
    }.visit(mv, uniqueMethods.keySet());

    mv.visitMaxs(1, 3);
    mv.visitEnd();
}
 

private static void generateRun(ClassVisitor cv, Type testType, int iThread, List<Actor> actors, List<Object> objArgs, boolean waitsEnabled) {
    int access = ACC_PUBLIC;
    Method m = new Method("call", RESULT_ARRAY_TYPE, NO_ARGS);
    GeneratorAdapter mv = new GeneratorAdapter(access, m,
        // Try-catch blocks sorting is required
        new TryCatchBlockSorter(cv.visitMethod(access, m.getName(), m.getDescriptor(), null, null),
            access, m.getName(), m.getDescriptor(), null, null)
    );
    mv.visitCode();
    // Create Result[] array and store it to a local variable
    int resLocal = createResultArray(mv, actors.size());
    // Call runner's onStart(iThread) method
    mv.loadThis();
    mv.getField(TEST_THREAD_EXECUTION_TYPE, "runner", RUNNER_TYPE);
    mv.push(iThread);
    mv.invokeVirtual(RUNNER_TYPE, RUNNER_ON_START_METHOD);
    // Number of current operation (starts with 0)
    int iLocal = mv.newLocal(Type.INT_TYPE);
    mv.push(0);
    mv.storeLocal(iLocal);
    // Invoke actors
    for (int i = 0; i < actors.size(); i++) {
        Actor actor = actors.get(i);
        // Add busy-wait before operation execution (for non-first operations only)
        if (waitsEnabled && i > 0) {
            mv.loadThis();
            mv.getField(TEST_THREAD_EXECUTION_TYPE, "waits", INT_ARRAY_TYPE);
            mv.push(i - 1);
            mv.arrayLoad(Type.INT_TYPE);
            mv.invokeStatic(UTILS_TYPE, UTILS_CONSUME_CPU);
        }
        // Start of try-catch block for exceptions which this actor should handle
        Label start, end = null, handler = null, handlerEnd = null;
        if (actor.handlesExceptions()) {
            start = mv.newLabel();
            end = mv.newLabel();
            handler = mv.newLabel();
            handlerEnd = mv.newLabel();
            for (Class<? extends Throwable> ec : actor.handledExceptions)
                mv.visitTryCatchBlock(start, end, handler, Type.getType(ec).getInternalName());
            mv.visitLabel(start);
        }
        // Load result array and index to store the current result
        mv.loadLocal(resLocal);
        mv.push(i);
        // Load test instance
        mv.loadThis();
        mv.getField(TEST_THREAD_EXECUTION_TYPE, "testInstance", OBJECT_TYPE);
        mv.checkCast(testType);
        // Load arguments for operation
        for (int j = 0; j < actor.arguments.length; j++) {
            pushArgumentOnStack(mv, objArgs, actor.arguments[j], actor.method.getParameterTypes()[j]);
        }
        // Invoke operation
        Method actorMethod = Method.getMethod(actor.method);
        mv.invokeVirtual(testType, actorMethod);
        // Create result
        mv.box(actorMethod.getReturnType()); // box if needed
        if (actor.method.getReturnType() == void.class) {
            mv.pop();
            mv.invokeStatic(RESULT_TYPE, RESULT_CREATE_VOID_RESULT);
        } else {
            mv.invokeStatic(RESULT_TYPE, RESULT_CREATE_VALUE_RESULT);
        }
        // Store result to array
        mv.arrayStore(RESULT_TYPE);
        // End of try-catch block
        if (actor.handlesExceptions()) {
            mv.visitLabel(end);
            mv.goTo(handlerEnd);
            mv.visitLabel(handler);
            storeExceptionResultFromThrowable(mv, resLocal, iLocal);
            mv.visitLabel(handlerEnd);
        }
        // Increment number of current operation
        mv.iinc(iLocal, 1);
    }
    // Call runner's onFinish(iThread) method
    mv.loadThis();
    mv.getField(TEST_THREAD_EXECUTION_TYPE, "runner", RUNNER_TYPE);
    mv.push(iThread);
    mv.invokeVirtual(RUNNER_TYPE, RUNNER_ON_FINISH_METHOD);
    // Return results
    mv.loadThis();
    mv.loadLocal(resLocal);
    mv.returnValue();
    mv.visitMaxs(1, 1);
    mv.visitEnd();
}