How to create an AdjustXform for georeferencing images

static IAdjustXform createAdjustXform(IPointCollection sourcePoints,
    IPointCollection targetPoints, ISpatialReference sr)throws Exception{
    //this example creates an AdjustXform
    IAdjustXform adjustXF = new AdjustXform();

    //set control points and the polynomial order used
    adjustXF.defineFromControlPoints(sourcePoints, targetPoints);
    adjustXF.setPolynomialApproximation(2);

    //using interpolation to do the adjustment
    adjustXF.setNaturalNeighbor(true);

    //you can also define the spatial reference of the xform
    adjustXF.setSpatialReferenceByRef(sr);
    return adjustXF;
}