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![image](https://user-images.githubusercontent.com/15622677/221121735-39571dc2-d771-493a-9d3c-14f8a8ee239f.png)
ReflectionPackableMethod类中 argument.getClass().getName()报空指针
            for (Object argument : arguments) {
                builder.addArgTypes(argument.getClass().getName());
                ByteArrayOutputStream bos = new ByteArrayOutputStream();
                multipleSerialization.serialize(url, serialize, argument.getClass(), argument, bos);
                builder.addArgs(bos.toByteArray());
            }
} else {
                if (protobufParameterCount > 0) {
                    throw new IllegalStateException("method params error method=" + methodName);
                }
            }
        } else {
            if (streamParameterCount > 0) {
                throw new IllegalStateException(
                    "method params error: unary method should not contain any StreamObserver."
                        + " method=" + methodName);
            }
            if (protobufParameterCount > 0 && returnClassProtobuf) {
                return false;
            }
            
            if (isMono(returnClass) || isRx(returnClass)) {
                return false;
            }
            if (protobufParameterCount <= 0 && !returnClassProtobuf) {
                return true;
            }
            
            if (GRPC_ASYNC_RETURN_CLASS.equalsIgnoreCase(returnClass.getName())
                && protobufParameterCount == 1) {
                return false;
            }
            
            if (TRI_ASYNC_RETURN_CLASS.equalsIgnoreCase(returnClass.getName())) {
                Class<?> actualReturnClass = (Class<?>) ((ParameterizedType) methodDescriptor.getMethod()
                    .getGenericReturnType()).getActualTypeArguments()[0];