public PacketError getRejectionError()
    {
        return rejectionError;
    }
Gets the error that will be sent to the sender of the inbound stanza that got rejected.

When the rejected stanza was a message, this error is added to a message that is sent (possibly also including
the message body as specified by {@link #setRejectionMessage(String)}). When the rejected stanza was an IQ or
Presence stanza, then the error is used in the error response. For these stanzas, this is a different stanza than
the optional Message stanza that is sent when {@link #setRejectionMessage(String)}) is (also) used.

@return An optional error to be included in an error response in reaction to the rejection.
xmppserver/src/main/java/org/jivesoftware/openfire/interceptor/PacketRejectedException.java