[PROJ] Starting JNI wrappers - a few questions

[Martin Desruisseaux]

Thanks Even for the tips; I will design accordingly (pool of relatively 
long lived PJ_CONTEXT, encoding assumed UTF-8). More questions to come 
maybe next week.

     Regards,

         Martin

Le 25/09/2019 à 17:27, Even Rouault a écrit :

>>      PJ_CONTEXT
>>
>> (...snip...)
> You can use a PJ_CONTEXT created by one thread in another thread. The golden
> rule is not to use in more than one thread at the same time as you stated
> above.
>
>> Are PJ_CONTEXT expected to be short lived (...snip...)
> Rather long lived. The PJ_CONTEXT caches the sqlite3 database handle, and even
> higher level objects. So createOperations() performance would suffer if you
> start from a new PJ_CONTEXT everytime.
>
>>      Disposal at shutdown time
>>
>> (...snip...)
> There shouldn't be any problem to just exit the JVM without terminating PROJ.
> The sqlite3 handle is on a read-only file, and only read-only operations are
> done, so nothing to corrupt.
>
>>      Encoding of std::string
>>
>> (...snip...)
> UTF-8 is more or less implied. The EPSG database is ingested from a UTF-8
> dump. People could potentially try to ingest non UTF-8 strings in import from
> WKT, but we could/should just state in the documentation that all strings
> ingested are expected to be UTF-8 (in which case all strings output by PROJ
> will be UTF-8 as well)