Hello César
Le 31/01/2018 à 16:35, César Martínez Izquierdo a écrit :
> Thank you Martin for the pointer to
> CoordinateOperationAuthorityFactory. However, I've failed to
> instantiate it: (...snip...) java.util.NoSuchElementException
>
Indeed, my mistake. After verification I saw that
CoordinateOperationAuthorityFactory is not registered in
META-INF/services. I filled a JIRA task on this issue:
https://issues.apache.org/jira/browse/SIS-393
In the meantime, the following trick should work. It is fragile because
of the cast, but this is a temporary solution (more on it below):
CoordinateOperationAuthorityFactory factory =
(CoordinateOperationAuthorityFactory) CRS.getAuthorityFactory("EPSG");
A more permanent solution will be to rely on the upcoming ISO 19111
revision. All those FooFactory interfaces where not derived from ISO
19111; they are GeoAPI additions. But latest ISO 19111 draft defines a
RegisterOperations interface with a findCoordinateOperations(…) method.
Once this standard is officially adopted, we plan to align on it.
> The documentation states that Java 7 is required, but I've seen that
> you are adapting the code now to Java 8 (in trunk), and removing Java
> 7 support (if I correctly understood the changes). What are your plans
> for the future? Will you move to Java 9 and drop Java 8 support? Have
> you considered keeping compatibility with several versions (e.g. 7 to 9)?
>
We try to keep compatibility with several versions. Despite having
branches for different JDK versions, Apache SIS should be runnable on
all Java versions above the target version except Java 9 (actually not
yet tested). The purpose of those branches is only to be ready when we
decide to upgrade the Java requirement, by allowing immediate use of new
Java features.
The reason for upgrading to Java 8 is for allowing the use of following
packages in public API. If it was not for this need (or if we needed
those packages only in non-public API), we could have stayed on Java 7
longer:
* java.time
* java.util.stream
Regarding Java 9, I'm not aware of any new classes or interfaces that we
would need to leverage in public API. Consequently we have no reason to
force the use of Java 9 at runtime any time soon (we may require Java 9
for building SIS, but not for using in other projects). My proposal is
to deploy either Java 8 files, or maybe multi-version JAR files for Java
8 and 9.
> I've seen that some projections are defined on EPSG but they are not
> currently supported on SIS (for instance Lambert azimuthal equal-area
> projection). Do you have a list of them?
The coordinate operation methods published in EPSG guidance notes are
listed there, together with an indication of whether it is implemented
in SIS or remain to be done:
https://issues.apache.org/jira/browse/SIS-212
In a few cases we have code pending in the Geotk project, but we need to
continue the intellectual property review
(http://svn.apache.org/repos/asf/sis/ip-review/) before to port them to
Apache SIS.
> Do you have plans to implement (some of) them?
At least the easy ones (a few coordinate operations there are merely
affine transforms with parameters expressed in a different way) and the
projections we can port from Geotk. When I will be able to do that
however is uncertain.
Regards,
Martin
