WFS2 includes two ways to check if an attribute does not have a value.
- PropertyIsNull can be used to check that a property exists; and that the value is empty.
- PropertyIsNil is used to check if a property exists at all
// test if "approval" equals "null"
filter = ff.isNull(ff.property("approved"));
// this example checks if approved exists at all
filter = ff.isNil(ff.property("approved"),"no approval available");
I also found that I had missed documenting how FeatureId can be used to look up a feature by name; or at least identifier.
filter = ff.id(selected);
Documentation harmed in the making of this post: