> Forgive me, if my comments are somewhat confusing.
> The isolated ERSI holes, are not added to the other inner rings. All isolated ESRI holes are added as interior rings to the polygon being processed.
Can you explain this some more?
> Prior to writing the converter I did some interactive experiments with ArcSDE. I found out, that ArcSDE actually accepts ESRI-loops sitting on the outer side on an interior ring in a JTS polygon.
Can you try the exverted and inverted polygons describe in the above article and tell me what happens? It should be as I expect but I have not used ArcSDE for over 4 years so I can't be sure if the issue is still as I described it.
> ArcSDE will even accept multiple loops sitting on the outside of the exterior ring in a JTS polygon. Such a polygon would need to be converted to a JTS multipolygon, if it going to be SFS/JTS valid. The converter will not perform such a conversion, as I think it is an error, to have such polygons in the first place.
This sounds like an exverted polygon. So, ESRI will accept it, but JTS (because it is OGC SFS based) will not?