public AbstractMessageDelegator<S> map( Class messageType, String methodName ) {
        // Lookup the method 
        Method m = findDelegate( methodName, messageType );
        if( m == null ) { 
            throw new RuntimeException( "Method:" + methodName 
                                        + " not found matching signature (MessageConnection, " 
                                        + messageType.getName() + ")" );
        }                                        
 
        if( log.isLoggable(Level.FINEST) ) {
            log.log(Level.FINEST, "Adding method mapping:{0} = {1}", new Object[]{messageType, m});
        }  
        methods.put( messageType, m );
        messageTypes = null;        
        return this;   
    }
Manually maps a specified method to the specified message type.
jme3-networking/src/main/java/com/jme3/network/util/AbstractMessageDelegator.java