Обсуждение: JDBC get object - (Geometry Postgis)
Greetings,
I'm trying to get a geometry (object) from the database through JDBC. I
read the postgis documentation but I think it's not actualized - there
isn't any org.postgresql.Connection object but a
org.postgresql.PGConnection that hasn't any such method as
adddataType().
Example from POSGIS documentation:
---
...
((org.postgresql.Connection)conn).addDataType("geometry","org.postgis.PGgeometry");
((org.postgresql.Connection)conn).addDataType("box3d","org.postgis.PGbox3d");
Statement s = conn.createStatement();
ResultSet r = s.executeQuery("select AsText(geom) as geom,id from
geomtable");
while( r.next() ) {
PGgeometry geom = (PGgeometry)r.getObject(1);
...
---
How could I retrieve a geometry object from a postgresql (7.3.2)
database with postgis 0.7.4? How do I make a mapping or something like
that? I believe that AsText() delivers a text and not an object...
thanks,
Pedro Salazar.
P.S.- If this email is too much postgis than postgresql, I apologize for
the off-topic message.
--
PS
pedro-b-salazar@ptinovacao.pt
PGP:0E129E31D803BC61
Pedro,
The geometry types are in the driver as
org.postgresql.geometric.PGcircle,PGline ....
Dave
On Tue, 2003-04-08 at 11:09, Pedro Salazar wrote:
> Greetings,
>
> I'm trying to get a geometry (object) from the database through JDBC. I
> read the postgis documentation but I think it's not actualized - there
> isn't any org.postgresql.Connection object but a
> org.postgresql.PGConnection that hasn't any such method as
> adddataType().
>
> Example from POSGIS documentation:
> ---
> ...
> ((org.postgresql.Connection)conn).addDataType("geometry","org.postgis.PGgeometry");
> ((org.postgresql.Connection)conn).addDataType("box3d","org.postgis.PGbox3d");
>
> Statement s = conn.createStatement();
> ResultSet r = s.executeQuery("select AsText(geom) as geom,id from
> geomtable");
> while( r.next() ) {
> PGgeometry geom = (PGgeometry)r.getObject(1);
> ...
> ---
>
> How could I retrieve a geometry object from a postgresql (7.3.2)
> database with postgis 0.7.4? How do I make a mapping or something like
> that? I believe that AsText() delivers a text and not an object...
>
> thanks,
> Pedro Salazar.
>
> P.S.- If this email is too much postgis than postgresql, I apologize for
> the off-topic message.
--
Dave Cramer <Dave@micro-automation.net>
On Tue, 2003-04-08 at 15:25, Dave Cramer wrote: > Pedro, > > The geometry types are in the driver as > > org.postgresql.geometric.PGcircle,PGline .... > > Dave Hi Dave, Those objects are defined as well in the postgresql database as data types, but how could I map them to postgis objects? Are them related or compatible? Or should I transform/convert in a postgres function? And, to retrieve a geometry object, is it enough to do a simple getObject(N) and after that cast it to the respective postgresql object? thanks, Pedro Salazar. -- PS pedro-b-salazar@ptinovacao.pt PGP:0E129E31D803BC61
Pedro, I think we have to put the code back which allows you to add types. I'm not sure where it went, but it appears to be gone?? Dave On Tue, 2003-04-08 at 11:38, Pedro Salazar wrote: > On Tue, 2003-04-08 at 15:25, Dave Cramer wrote: > > Pedro, > > > > The geometry types are in the driver as > > > > org.postgresql.geometric.PGcircle,PGline .... > > > > Dave > > Hi Dave, > > Those objects are defined as well in the postgresql database as data > types, but how could I map them to postgis objects? Are them related or > compatible? Or should I transform/convert in a postgres function? > > And, to retrieve a geometry object, is it enough to do a simple > getObject(N) and after that cast it to the respective postgresql object? > > thanks, > Pedro Salazar. -- Dave Cramer <Dave@micro-automation.net>
Pedro,
Sorry I was too quick, the code is still there the name of the
connection is different now
cast it to org.postgresql.PGConnection, then call
addDataType
here are the comments for it
/*
* This allows client code to add a handler for one of org.postgresql's
* more unique data types.
*
* <p><b>NOTE:</b> This is not part of JDBC, but an extension.
*
* <p>The best way to use this is as follows:
*
* <p><pre>
* ...
*
((org.postgresql.Connection)myconn).addDataType("mytype","my.class.name");
* ...
* </pre>
*
* <p>where myconn is an open Connection to org.postgresql.
*
* <p>The handling class must extend org.postgresql.util.PGobject
*
* @see org.postgresql.util.PGobject
*/
public void addDataType(String type, String name)
{
objectTypes.put(type, name);
}
by default the following are defined, so you can overwrite them as long
as you use the same keys.
private static final String defaultObjectTypes[][] = {
{"box", "org.postgresql.geometric.PGbox"},
{"circle", "org.postgresql.geometric.PGcircle"},
{"line", "org.postgresql.geometric.PGline"},
{"lseg", "org.postgresql.geometric.PGlseg"},
{"path", "org.postgresql.geometric.PGpath"},
{"point", "org.postgresql.geometric.PGpoint"},
{"polygon", "org.postgresql.geometric.PGpolygon"},
{"money", "org.postgresql.util.PGmoney"}
};
Dave
On Tue, 2003-04-08 at 10:51, Dave Cramer wrote:
> Pedro,
>
> I think we have to put the code back which allows you to add types.
>
> I'm not sure where it went, but it appears to be gone??
>
> Dave
> On Tue, 2003-04-08 at 11:38, Pedro Salazar wrote:
> > On Tue, 2003-04-08 at 15:25, Dave Cramer wrote:
> > > Pedro,
> > >
> > > The geometry types are in the driver as
> > >
> > > org.postgresql.geometric.PGcircle,PGline ....
> > >
> > > Dave
> >
> > Hi Dave,
> >
> > Those objects are defined as well in the postgresql database as data
> > types, but how could I map them to postgis objects? Are them related or
> > compatible? Or should I transform/convert in a postgres function?
> >
> > And, to retrieve a geometry object, is it enough to do a simple
> > getObject(N) and after that cast it to the respective postgresql object?
> >
> > thanks,
> > Pedro Salazar.
--
Dave Cramer <Dave@micro-automation.net>