Tom,
yes FindMatches() is what is needed for your use case and it is not
currently available in the Java bindings. That would require someone to
write the appropriate typemap(s) to map the C types to Java types.
Even
Le 13/08/2026 à 13:15, Tom Moore via gdal-dev a écrit :
Hi all,
I'm running into a case where SpatialReference.AutoIdentifyEPSG()
fails on a completely standard, well-formed ESRI-dialect .prj file,
even though the underlying PROJ identification machinery
(proj_identify(), as exercised via "projinfo --identify") resolves it
correctly with 100% confidence. I'd like to know whether this is a
known limitation, and whether there's a recommended workaround for
Java bindings users specifically, since FindMatches() isn't exposed there.
Environment:
- GDAL 3.11.1 (Windows build)
- PROJ 9.6.2
- Java bindings (org.gdal.osr / SWIG)
Input WKT (contents of a shapefile .prj, ESRI dialect):
PROJCS["NAD_1983_UTM_Zone_11N",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-117.0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]]
QGIS correctly identifies this as EPSG:26911.
What I tried (Java):
SpatialReference srs = new SpatialReference();
srs.ImportFromESRI(lines); // also tried plain ImportFromWkt()
but got the same result
srs.SetAxisMappingStrategy(osrConstants.OAMS_TRADITIONAL_GIS_ORDER);
try {
srs.AutoIdentifyEPSG();
} catch (Exception ex) {
System.out.println("Exception: " + ex.getMessage());
}
System.out.println("code = " + srs.GetAuthorityCode(null));
Result:
Exception: OGR Error: Unsupported SRS
code = null
gdal.GetLastErrorType() / GetLastErrorMsg() are empty. No additional
diagnostic detail is surfaced beyond the generic exception.
I ruled out several things before suspecting this is a
AutoIdentifyEPSG() limitation rather than an environment/config issue
on my end:
1. proj.db itself is correct. Confirmed by mounting the exact same
proj.db (from the PROJ 9 data directory used by my JAva app) into a
clean ghcr.io/osgeo/gdal:ubuntu-small-latest
<http://ghcr.io/osgeo/gdal:ubuntu-small-latest> container and running
`gdalsrsinfo -e` against the same .prj file. It resolved to EPSG:26911
correctly, full WKT2 with all authority IDs.
2. PROJ_LIB / PROJ_DATA environment variables are set correctly and
confirmed using System.getenv() to be visible to the process
3. Tried MorphFromESRI() (both via ImportFromESRI() alone, and
combined with an explicit MorphFromESRI() call) - no change.
4. Tried explicit SetAxisMappingStrategy(OAMS_TRADITIONAL_GIS_ORDER)
before calling AutoIdentifyEPSG() - no change.
5. Ran the projinfo.exe from the gdal build that I am using with the
Java app directly against the same .prj file:
projinfo.exe --identify fmu.prj
...
Identification match count: 1
EPSG:26911: 100 %
So proj_identify() / FindMatches()-equivalent logic resolves this WKT
perfectly in the exact same native build, but AutoIdentifyEPSG() fails
on it.
This looks consistent with a few things I found in the tracker/mailing
list archives while investigating:
- https://trac.osgeo.org/gdal/ticket/6188 -- maintainer comment noting
AutoIdentifyEPSG() has "very limited capabilities" and would need
fuzzy matching to handle inexact datum/ellipsoid names, "especially
when dealing with WKT coming from ESRI."
- https://github.com/OSGeo/gdal/issues/4038 -- near-identical repro
WKT (ESRI-dialect UTM), with a maintainer noting AutoIdentifyEPSG()
can return OGRERR_UNSUPPORTED_SRS while having still injected partial
AUTHORITY tags into sub-nodes. This matches what I see when printing
the WKT after the failed call (DATUM gets EPSG:6269, but the top-level
PROJCS never gets an ID).
- https://github.com/OSGeo/gdal/issues/2303 -- shows the standard
Python workaround (fall back to FindMatches() when AutoIdentifyEPSG()
fails), which leads to my second question below.
Questions:
1. Is AutoIdentifyEPSG() failing on this ESRI-dialect NAD83/UTM WKT a
known limitation, or does this look like a genuine regression/bug
worth filing?
2. FindMatches() does not appear to be exposed in the Java SWIG
bindings (org.gdal.osr.SpatialReference). Is that correct, or am I
missing something? If it's genuinely absent, is there any appetite for
adding it, given it's the documented fallback for exactly this
situation in other language bindings?
3. Short of shelling out to "projinfo --identify" as a subprocess, is
there a recommended in-process approach for Java bindings users to
reach the same identification logic?
Happy to provide a minimal reproducible test case / file a tracker
issue if that's useful, but I wanted to check here first in case this
is already understood behavior.
Thanks,
Tom
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