Hi Ede,

I made a very short test which was successful. I can't do more tests before 
July 11.  Meanwhile I encourage everybody else to test with all kind of GeoJSON 
files from various places. Especially different web services delivering data as 
GeoJSON are interesting because we could later make OpenJUMP as a client for 
such services.

-Jukka Rahkonen-

edgar soldin wrote 

> hey Jukka,

> please try r4945 or later.

..ede

On 27.06.2016 11:47, Rahkonen Jukka (MML) wrote:
> Yes, sure, having all as strings is a good start.
> 
>  
> -Jukka-
> 
> edgar soldin wrote:
> 
>> Jukka,
> 
>> could you live with all attributes being read as Strings for now? 
>> ..ede
> 
> On 27.06.2016 08:35, Jukka Rahkonen wrote:
>>> Hi,
>>>
>>> Json datatypes http://www.tutorialspoint.com/json/json_data_types.htm do 
>>> not map perfectly with OJ datatypes. Strings can be separated from numbers, 
>>> though, but there is another problem in missing schema. Each feature can 
>>> have different attributes.
>>>
>>> I believe that GDAL is scanning the GeoJSON file twice for finding all the 
>>> attributes which appear in the data and analyzing their datatypes. Rather 
>>> often GeoJSON is converted from GIS data and then schema is fixed so that 
>>> all features have same set of attributes and empty ones are marked as NULL. 
>>> Still it is hard to know the type of attribute if it is NULL.
>>>
>>> Code for reading GeoJSON with GeoTools is at 
>>> https://github.com/geotools/geotools/tree/master/modules/unsupported
>>> /g
>>> eojson
>>>
>>> An easy start could be to read the first one feature and build 
>>> schema with attribute types double, string, boolean. But what to do 
>>> if there are null values? Read first hundred? Read until first not 
>>> null? Or let user make a header line with schema into a separate 
>>> file "basename.jsont" like with the GDAL CSV driver 
>>> http://www.gdal.org/drv_csv.html
>>>
>>> attr_1:string;attr_2:integer;attr_3:double
>>>
>>> Sorry that I can't give simple answers, I thought it would be easier and 
>>> handled by JTS already.
>>>
>>> -Jukka-
>>>
>>> edgar.sol...@web.de kirjoitti 2016-06-26 17:19:
>>>> hey Jukka,
>>>>
>>>> attributes do not seem to carry a type in GeoJSON.. any idea how 
>>>> this is supposed to be parsed?
>>>>
>>>> ..ede
>>>>
>>>> On 23.06.2016 16:20, Jukka Rahkonen wrote:
>>>>> Hi Ede,
>>>>>
>>>>> Please find attached. I included some small samples in both JML and 
>>>>> GeoJSON. For the conversion I used ogr2ogr:
>>>>>
>>>>> ogr2ogr -f geojson output.json input.jml
>>>>>
>>>>> Test data is not perfect:
>>>>>
>>>>> - I just digitized some features and they may be outside the real 
>>>>> area of the EPSG:4326 which is default in GeoJSON 
>>>>> (-90,-180,90,180)
>>>>> - GDAL warned that DateTime type is not natively supported
>>>>>
>>>>> For handling projections with ogr2ogr use source and target srs 
>>>>> parameters as
>>>>>
>>>>> ogr2ogr -f geojson -s_srs epsg:3067 -t_srs epsg:4326 output.json 
>>>>> input.jml
>>>>>
>>>>> -Jukka-
>>>>>
>>>>> edgar.sol...@web.de kirjoitti 2016-06-23 15:56:
>>>>>> Jukka,
>>>>>>
>>>>>> do you have an example dataset to tiner with for me?
>>>>>>
>>>>>> ..ede
> 
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