}
// To prevent looping, an entity MUST NOT include a receipt request (i.e., the <request/> element) in an ack message (i.e., a message stanza that includes the <received/> element).
// A sender MUST include an 'id' attribute on every content message that requests a receipt, so that the sender can properly track ack messages.
if (message.getExtension(Received.class) == null && message.getId() != null) {
// Add a delivery receipt request.
message.getExtensions().add(new Request());
}
}
}
}
});