public void setRejectionMessage(String rejectionMessage) {
        this.rejectionMessage = rejectionMessage;
    }
Sets the text to include in a message that will be sent to the sender of the packet
that got rejected or {@code null} if no message will be sent to the sender of the
rejected packet. By default, no message will be sent.

@param rejectionMessage the text to include in the notification message for the rejection.
xmppserver/src/main/java/org/jivesoftware/openfire/interceptor/PacketRejectedException.java