src/main/java/org/nustaq/serialization/FSTObjectOutput.java
protected void objectWillBeWritten( Object obj, int streamPosition ) {
        if (listener != null) {
            listener.objectWillBeWritten(obj, streamPosition);
        }
    }
protected void objectWillBeWritten( Object obj, int streamPosition ) {
        if (listener != null) {
            listener.objectWillBeWritten(obj, streamPosition);
        }
    }
hook for debugging profiling. register a FSTSerialisationListener to use
@param obj
@param streamPosition