protected void send( byte channel, RpcResponseMessage msg ) {
        if( channel >= 0 ) {
            connection.send(channel, msg);
        } else {
            connection.send(msg);
        }
    }
Removes a previously registered handler for the specified
 object ID.
jme3-networking/src/main/java/com/jme3/network/service/rpc/RpcConnection.java