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From Niclas Hedhman <nic...@hedhman.org>
Subject Re: GeoSpatial Query support
Date Wed, 03 Jun 2015 16:11:43 GMT
Thanks Chris...

Adam,
Well, there are a few things worth mentioning;

Zest isn't your regular project, and we have (for instance) fairly advanced
type handling system. I would be delighted to explain it greater detail,
but I think that is out of scope right here. What I need to mention is that
a method
     String getAbc();
is not a property in our world;
    Property<String> abc();
is a property, and from this little fact we derive a lot of strengths. For
instance, in the current scope, Query, we do things like (I hope the sample
is small enough);

public interface Address
{
    Property<String> zipCode();
}

QueryBuilder<Person> qb = module.newQueryBuilder( Person.class );
Address template = templateFor( Address.class );

Query<Person> q = qb.where(
    eq( template.zipCode(), "90210" )
).newQuery( unitOfWork );

for( Person p : query )
{ ... }


(unitOfWork is the bounding operations of all storage related operations.
Kind of transactions, but not tying up resources in backing stores)

In reality, this means that it is not easy to any third-party
library/system at the core of our API/SPI.


HOWEVER, that said, we are also quite capable of integrating arbitrary code
into our realm, since we are capable of "applying" the implementing methods
on any interface. For instance;

    module.transients Map.class ).withMixins( HashMap.class,
MyPutMixin.class);

in the bootstrap allows me to;

    Map map = module.newTransient( Map.class );

which has a single method replaced in the Map interface, but all other are
backed by HashMap.
So, IF SIS are primarily based around interfaces, then that would be great
and we can possibly leverage quite a bit, especially at what we call
"Library" level, i.e. not part of the Core runtime itself, which we try to
keep free of dependencies (only ASM).

SIS definitely provides a lot of reference information that is good to know
being close by, so let's take one step at a time.

I am not the Geo expert here, and not sure how much energy Jiri has left in
him... ;-)

Cheers

On Wed, Jun 3, 2015 at 11:12 PM, <estrada.adam@gmail.com> wrote:

> Most excellent, Dr. Mattmann! @sis, we should definitely collaborate with
> @zest on this one. If they are implementing simple query functionality,
> maybe they can take advantage of the work Marc has already done and also
> use the projection support Martin has been committing.
>
> Thoughts?
> Adam
>
> Sent from my iPhone
>
> > On Jun 3, 2015, at 11:00 AM, Mattmann, Chris A (3980) <
> chris.a.mattmann@jpl.nasa.gov> wrote:
> >
> > Maybe this is a good integration point for sis.apache.org?
> >
> > CC’ing the Apache SIS list for visibility
> >
> > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> > Chris Mattmann, Ph.D.
> > Chief Architect
> > Instrument Software and Science Data Systems Section (398)
> > NASA Jet Propulsion Laboratory Pasadena, CA 91109 USA
> > Office: 168-519, Mailstop: 168-527
> > Email: chris.a.mattmann@nasa.gov
> > WWW:  http://sunset.usc.edu/~mattmann/
> > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> > Adjunct Associate Professor, Computer Science Department
> > University of Southern California, Los Angeles, CA 90089 USA
> > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> >
> >
> >
> >
> > -----Original Message-----
> > From: Jiri Jetmar <juergen.jetmar@gmail.com>
> > Reply-To: "dev@zest.apache.org" <dev@zest.apache.org>
> > Date: Wednesday, June 3, 2015 at 7:45 AM
> > To: "dev@zest.apache.org" <dev@zest.apache.org>
> > Subject: Re: GeoSpatial Query support
> >
> >> Hi Niclas,
> >>
> >> this ST_XX follows the http://en.wikipedia.org/wiki/DE-9IM and
> >> http://en.wikipedia.org/wiki/Simple_Features standards that are indeed
> >> "SQL" related. I used this expression to be similar with e.g. PostGIS,
> >> means when someone knows how to use spatial expressions on PostGIS,
> >> he should be able to understand the Apache Zest approach.
> >>
> >> But clearly I can "lowercase" the ST_Xx expressions in the code.
> >>
> >> Cheers,
> >> jj
> >>
> >> 2015-06-03 16:22 GMT+02:00 Niclas Hedhman <niclas@hedhman.org>:
> >>
> >>> Jiri,
> >>> There is one thing that bothers me; ST_Within and similar doesn't
> follow
> >>> the Java convention at all. I have researched and seen that many DBs
> >>> uses
> >>> this, but don't you think we should lower case st_ instead for methods?
> >>>
> >>>
> >>> Cheers
> >>> --
> >>> Niclas Hedhman, Software Developer
> >>> http://zest.apache.org - New Energy for Java
> >
>



-- 
Niclas Hedhman, Software Developer
http://zest.apache.org - New Energy for Java

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