There is "Expression/NIL".
But it is not a literal, it's a property :/ A pseudo-property I'd say.
See org.geotools.filter.expression.NullPropertyAccessorFactory
It definitely has uses, it's used in both app-schema and CSW mappings.
A literal would be more appropriate.
Regards
Niels
On 15/05/2020 04:15, Jody Garnett wrote:
I have been updating mbstyle filter to support expressions, and ran
into something odd when writing tests (using ECQL to compare the
output). It appears that a literal null value does not have a
representation in ECQL. Indeed right now this causes a nice stacktrace
to ECQL.toECQL( filter ).
I am not sure how we made it this far without one? Options:
* '' - empty string is not quite NULL but close
* NULL - already a reserved word, may actually be correct?
At a minimum I would like to throw a kinder error message -
ExpressionToText:
public Object visit(Literal expression, Object extraData) {
...
} else {
if (literal == null) {
throw new NullPointerException("ECQL does not support null literal
value");
} else {
String escaped = literal.toString().replaceAll("'", "''");
output.append("'" + escaped + "'");
}
}
return output;
}
Searching online is difficult as the presence of "IS NULL" and "IS NOT
NULL".
--
Jody Garnett
_______________________________________________
GeoTools-Devel mailing list
GeoTools-Devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geotools-devel
_______________________________________________
GeoTools-Devel mailing list
GeoTools-Devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geotools-devel
