Fix writing XYM geometries as WKB

[Kontinuation]

Fixes#733

Please note that we must specify outputDimension = 4 when writing geometries with M dimension, even when the geometry is XYM instead of XYZM. This behavior is the same as WKTWriter.

[mprins]

this is incorrect for a new file

[Kontinuation]

All source code in this file is taken from WKTWriter.java, which is an old file. Should we update the copyright header or preserve the copyright header of the file where it originates from?

[jodygarnett]

I do not think it needs to hold things up much, the options are:

/*
* Copyright (c) 2016 Vivid Solutions, and others
*

Or explicitly:

/*
* Copyright (c) 2025 your name
* Copyright (c) 2016 Vivid Solutions
*

[Kontinuation]

Issue #733 is closed but the problem still exists in the latest master.

[jiayuasu]

@jodygarnett@dr-jts Would you please merge this PR? We are working on adding Geo support into Apache Iceberg and Parquet Java reader and writer. JTS is a fundamental lib in this process. WKB is the encoding mechanism used in all these PRs.

[jiayuasu]

@jnh5y CC James too 🙏🏻

[Kontinuation]

I'd like to provide more context for the problem we are solving. Given the following MULTILINESTRING M geometry:

Stringwkt = "MULTILINESTRING M((1 1 1, 2 2 2))";
WKTReaderwktReader = newWKTReader();
GeometrygeometryBefore = wktReader.read(wkt);

Writing it using WKBWriter and read it back using WKBReader will result in a MULTILINESTRING Z:

WKBWriterwkbWriter = newWKBWriter(3);
byte[] write = wkbWriter.write(geometryBefore);
WKBReaderwkbReader = newWKBReader();
GeometrygeometryAfter = wkbReader.read(write);
System.out.println(Arrays.asList(geometryAfter.getCoordinates())); // [(1.0, 1.0, 1.0), (2.0, 2.0, 2.0)]

If we use WKTWriter and WKTReader for serializing and deserializing the MULTILINESTRING M geometry, we don't see the "phantom" Z ordinate, but we still lose the M ordinate:

WKTWriterwktWriter = newWKTWriter(3);
Stringwrite = wktWriter.write(geometryBefore);
GeometrygeometryAfter = wktReader.read(write);
System.out.println(Arrays.asList(geometryAfter.getCoordinates())); // [(1.0, 1.0, NaN), (2.0, 2.0, NaN)]

We found that JTS will only output M ordinate when outputDimension > 3, so M is always treated as the 4th dimension, regardless of whether the coordinates are XYM or XYZM. Setting outputDimension as 4 when using WKTWriter generates the MULTILINESTRING M(...) WKT string we wanted:

WKTWriterwktWriter = newWKTWriter(4);
Stringwrite = wktWriter.write(geometryBefore);
System.out.println(write); // MULTILINESTRING M((1 1 1, 2 2 2))GeometrygeometryAfter = wktReader.read(write);
System.out.println(Arrays.asList(geometryAfter.getCoordinates())); // [(1.0, 1.0 m=1.0), (2.0, 2.0 m=2.0)]

I believe that WKBWriter should behave the same as WKTWriter. However, specifying outputDimensions as 4 results in the following exception:

WKBWriterwkbWriter = newWKBWriter(4);
byte[] write = wkbWriter.write(geometryBefore); // <- exception raised here// java.lang.IllegalArgumentException: Invalid ordinate index: 3////	at org.locationtech.jts.geom.CoordinateXYM.getOrdinate(CoordinateXYM.java:140)//	at org.locationtech.jts.geom.impl.CoordinateArraySequence.getOrdinate(CoordinateArraySequence.java:260)//	at org.locationtech.jts.io.WKBWriter.writeCoordinate(WKBWriter.java:524)//	at org.locationtech.jts.io.WKBWriter.writeCoordinateSequence(WKBWriter.java:502)//	at org.locationtech.jts.io.WKBWriter.writeLineString(WKBWriter.java:425)//	at org.locationtech.jts.io.WKBWriter.write(WKBWriter.java:388)//	at org.locationtech.jts.io.WKBWriter.writeGeometryCollection(WKBWriter.java:454)//	at org.locationtech.jts.io.WKBWriter.write(WKBWriter.java:395)//	at org.locationtech.jts.io.WKBWriter.write(WKBWriter.java:367)

This PR resolves the above issue by making the behavior of WKBWriter consistent with WKTWriter. No Z or M ordinates will be written with outputDimension = 3:

WKBWriterwkbWriter = newWKBWriter(3);
byte[] write = wkbWriter.write(geometryBefore);
WKBReaderwkbReader = newWKBReader();
GeometrygeometryAfter = wkbReader.read(write);
System.out.println(Arrays.asList(geometryAfter.getCoordinates())); // [(1.0, 1.0), (2.0, 2.0)]

The M ordinate will be written as expected with outputDimension = 4:

WKBWriterwkbWriter = newWKBWriter(4);
byte[] write = wkbWriter.write(geometryBefore);
WKBReaderwkbReader = newWKBReader();
GeometrygeometryAfter = wkbReader.read(write);
System.out.println(Arrays.asList(geometryAfter.getCoordinates())); // [(1.0, 1.0 m=1.0), (2.0, 2.0 m=2.0)]

[jiayuasu]

@dr-jts@jodygarnett@jnh5y

Hi Martin, Jody, and James,

This is Jia from Wherobots, Apache Sedona.

Iceberg and Parquet have adopted WKB as the default encoding for geometry, and we’re currently working on adding JTS as a dependency of Iceberg and Parquet geometry. This change will have a broad impact across the ecosystem.

Could you please review and consider merging this PR? Or let us know what’s needed to get it across the finish line?

Thanks!
Jia