Hi Larry Reeder, >> Not too bad. Could you fill a bug report so that we remember there is a >> fix to do on this plugin. >> > Sure, done. >
I could not reproduce the problem with mixed geometry, but found a bug (NPE) for null non-numeric attributes. I think the NPE you get is due to this bug (null attributes) and not due to empty geometry collections. I committed the change. When you'll have time, please, can you tell me it the problem is fixed. PS I also fixed null attributes extracted from database as 0 instead of null and now return GEOMETRYCOLLECTION EMPTY for null geometries, as Martin suggested. Thanks for the help Michaël >> Did you already use the "Edit>Extract>Extract by geometry type" PlugIn ? >> It is perfectly suited to handle shapefile with heterogeneous geometries. >> I'd prefer this solution from deleting empty geometries without letting >> the user know. >> Maybe we can through a more explicit message to the user trying to >> export a heterogeneous shapefile to make him know about this tool. >> >> > > I didn't know about the "Extract by geometry type" plugin. Very > handy! I tried it and it extracted the polygon (area) features, but > not the geometrycollection features. I'm not familiar enough with this > plugin to determine if this behavior would be surprising to a user, > but it would let the user accomplish the task of filtering out the > empty geometries. > > >From a user's standpoint, I think it would be helpful if the shapefile > export referred the user to "Extract by geometry type" plugin when the > user tries to export a mixed-geometry layer to a shapefile. > > -lreeder > > >> Michaël >> >>> -lreeder >>> >>> 2010/1/28 Michaël Michaud <michael.mich...@free.fr>: >>> >>> >>>> Martin Davis a écrit : >>>> >>>> >>>>> I think in the past I"ve used the convention that null geometry is >>>>> represented as GEOMETRYCOLLECTION EMPTY. That way most or all of the >>>>> JUMP functions should still work, but the user doesn't have to try and >>>>> distinguish between a real geometry and one which is just a placeholder >>>>> for null. >>>>> >>>>> >>>>> >>>> Seems the best approach. I already saw this behaviour in OJ. Must check >>>> how postgis driver manage this case. >>>> >>>> >>>>> Ideally JUMP would be able to handle null geometries in the GEOMETRY >>>>> column as well - this should be fairly easy to add in, since it mostly >>>>> just means checking and returning before doing anything. >>>>> >>>>> >>>>> >>>> Do you mean returning a GEOMETRYCOLLECTION EMPTY instead of null in >>>> some base classes like BasicFeature.getGeometry() ? >>>> Should be interesting to try... >>>> >>>> Michaël >>>> >>>> >>>>> Rahkonen Jukka wrote: >>>>> >>>>> >>>>> >>>>>> Hi, >>>>>> >>>>>> It would be a correct behaviour to get nulls instead of zeros, I hope >>>>>> you can fix it. But check what happens if some attribute in a table or >>>>>> in the result set of a query contains only NULLs. The attribute field >>>>>> should still appear to OpenJUMP layer schema, and it should be of a >>>>>> correct data type. >>>>>> >>>>>> More fundamental question is what to do if geometry field is NULL. It is >>>>>> not so uncommon situation with databases, and the aim of many GIS >>>>>> projects is just to add spatial data for existing objects with already >>>>>> known attribute data by locating them on map. >>>>>> >>>>>> At present if the result of a PostGIS query contains only NULL >>>>>> geometries OpenJUMP throws a Null Pointer Exception. If there are both >>>>>> real geometries and NULL geometries in the result se, the lines which >>>>>> are missing geometry are skipped. >>>>>> >>>>>> A DB Query Plugin by Larry Reeder is using a workaroud that has been >>>>>> very usable for me: if geometry is missing the plugin creates a default >>>>>> geometry as a little rectangle polygon at the origo. By that way user >>>>>> gets the schema and attributes to OpenJUMP even if the geometry is >>>>>> empty. What is missing is a clever tool for digitizing the real geometry >>>>>> and inserting it in place of the default geometry. >>>>>> >>>>>> So what do developers think about what to do with features which do not >>>>>> have geometry? I am remembering that JUMP itself does not necessarily >>>>>> need geometry and I am rather sure that I have even seen such things in >>>>>> OpenJUMP. I quess I got them to OpenJUMP through opening some shapefile. >>>>>> >>>>>> -Jukka Rahkonen- >>>>>> >>>>>> >>>>>> >>>>>> Michaël Michaud wrote: >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>>> Hi, >>>>>>> >>>>>>> I've got a question for database experts. >>>>>>> In DatabaseQueryPlugIn, the following JDBC methods are used to get >>>>>>> numeric attributes from database features >>>>>>> - ResultSet.getInt() >>>>>>> - ResultSet.getDouble() >>>>>>> those methods return an int and a double, even if the >>>>>>> database contains >>>>>>> NULL >>>>>>> NULL : getInt() --> 0 >>>>>>> NULL : getDouble() --> 0.0 >>>>>>> I think that OpenJUMP should get a null value each time the database >>>>>>> contains a NULL value. >>>>>>> >>>>>>> If this there is no special reason to use those methods, I'll >>>>>>> change the >>>>>>> code to get null instead of 0 in this special cases. >>>>>>> >>>>>>> Thanks for any suggestion >>>>>>> >>>>>>> Michaël >>>>>>> >>>>>>> NB : I noticed another problem with null handling in >>>>>>> SimpleQueryPlugIn. >>>>>>> I fixed it in the svn that way : >>>>>>> select features from layer1 where name = (empty combo box) >>>>>>> now returns >>>>>>> empty strings AND nulls (empty strings and null are very similar from >>>>>>> the end-user point of view) >>>>>>> I added "is null" as a function to be able to differentiate null from >>>>>>> empty string cases >>>>>>> There maybe some corner cases which are still not perfectly handled >>>>>>> (when there are null in the dataset and the operator is not >>>>>>> "equal" for >>>>>>> example) >>>>>>> >>>>>>> >>>>>>> >>> ------------------------------------------------------------------------------ >>> The Planet: dedicated and managed hosting, cloud storage, colocation >>> Stay online with enterprise data centers and the best network in the >>> business >>> Choose flexible plans and management services without long-term contracts >>> Personal 24x7 support from experience hosting pros just a phone call away. >>> http://p.sf.net/sfu/theplanet-com >>> _______________________________________________ >>> Jump-pilot-devel mailing list >>> Jump-pilot-devel@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel >>> >>> >>> >>> >> ------------------------------------------------------------------------------ >> The Planet: dedicated and managed hosting, cloud storage, colocation >> Stay online with enterprise data centers and the best network in the business >> Choose flexible plans and management services without long-term contracts >> Personal 24x7 support from experience hosting pros just a phone call away. >> http://p.sf.net/sfu/theplanet-com >> _______________________________________________ >> Jump-pilot-devel mailing list >> Jump-pilot-devel@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel >> >> > > ------------------------------------------------------------------------------ > The Planet: dedicated and managed hosting, cloud storage, colocation > Stay online with enterprise data centers and the best network in the business > Choose flexible plans and management services without long-term contracts > Personal 24x7 support from experience hosting pros just a phone call away. > http://p.sf.net/sfu/theplanet-com > _______________________________________________ > Jump-pilot-devel mailing list > Jump-pilot-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > > > ------------------------------------------------------------------------------ The Planet: dedicated and managed hosting, cloud storage, colocation Stay online with enterprise data centers and the best network in the business Choose flexible plans and management services without long-term contracts Personal 24x7 support from experience hosting pros just a phone call away. http://p.sf.net/sfu/theplanet-com _______________________________________________ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel
