@Override
    public void cloneFields(Cloner cloner, Object original) {
        this.controlPoints = cloner.clone(controlPoints);
        if (segmentsLength != null) {
            this.segmentsLength = new ArrayList<>(segmentsLength);
        }
        this.CRcontrolPoints = cloner.clone(CRcontrolPoints);
        if (knots != null) {
            this.knots = new ArrayList<>(knots);
        }
        this.weights = cloner.clone(weights);
    }
Callback from {@link com.jme3.util.clone.Cloner} to convert this
shallow-cloned spline into a deep-cloned one, using the specified cloner
and original to resolve copied fields.

@param cloner the cloner that's cloning this spline (not null)
@param original the object from which this spline was shallow-cloned (not
null, unaffected)
jme3-core/src/main/java/com/jme3/math/Spline.java