I Have a service method that returns a `ResponseEntity<List<Attachment>>` and its hystrix `fallback` method must also return a `ResponseEntity<List<Attachment>>`.   
The problem is that I need to return a String message that clarifies the error to the user instead of returning a new `Arraylist<>()`  

- Here is my method

```
@Override
@HystrixCommand(fallbackMethod = "getAttachmentsFallback")
public ResponseEntity<List<AttachmentDto>> getAttachments(IAttachable entity) {
    List<AttachmentDto> attachments = client.getAttachments(entity.getAttachableId(), entity.getClassName(),
            entity.getAppName());
    return new ResponseEntity<List<AttachmentDto>>(attachments, HttpStatus.OK);
}

```

And that's its fallback

```
public ResponseEntity<List<AttachmentDto>> getAttachmentsFallback(IAttachable entity, Throwable e) {
    //I need to return a String instead of the new Arraylist<AttachmentDto>() 
    return new ResponseEntity<List<AttachmentDto>>(new ArrayList<AttachmentDto>(), HttpStatus.INTERNAL_SERVER_ERROR);
}

```