Support @org.checkerframework.checker.nullness.compatqual.NullableDecl etc.

[PhilippWendler]

Guava 23.6 has switched from using javax.annotation.Nonnull to org.checkerframework.checker.nullness.compatqual.NullableDecl for non-null parameters etc. Please support this annotation (and possibly the other annotations from the same package), because otherwise SpotBugs creates a lot of false alarms when calling Guava methods. I tested this with SpotBugs 3.1.1.

[iloveeclipse]

@PhilippWendler : it would be great if you could provide here a map which checker annotation corresponds to which "old" annotation.

The fix itself will be probably trivial (see for example #182).

[PhilippWendler]

Thanks.

It seems that org.checkerframework.checker.nullness.compatqual.NullableDecl for Nullable and org.checkerframework.checker.nullness.compatqual.NonNullDecl for NonNull would at least need to be supported.

There are more annotations in org.checkerframework.checker.nullness.qual for more complex nullness analysis (the above annotations are the compatibility annotations for Java 7 code), but I am not sure whether SpotBugs could support them, and it seems Guava does not use them. Maybe just org.checkerframework.checker.nullness.qual.Nullable and org.checkerframework.checker.nullness.qual.NonNull for now? This would allow Java 8 code to keep using annotations named Nullable instead of NullableDecl.
If SpotBugs supports it, the qual annotations can also be used on types, not only on declarations.

For reference: I have this from JetBrains/kotlin#1421, which is the PR that the Guava guys have submitted for the Kotlin nullness analyzer. It mentions these four annotations here.

[philipl]

This was fixed by #539, right?

[iloveeclipse]

Yep.

[anatoliy-balakirev]

Hi. I'm trying to use guava 25.1-jre, namely MoreObjects.toStringHelper().add("name", value), where signature looks like this:
public ToStringHelper add(String name, @ org.checkerframework.checker.nullness.qual.Nullable Object value)

I'm passing in a value (name is just a string literal), which is marked with old @ javax.annotation.CheckForNull and getting some errors from spotbugs (version 3.1.3):

[INFO] Total bugs: 12
[INFO] Null passed for non-null parameter of com.google.common.base.MoreObjects$ToStringHelper.add(String, Object) in ...

Is that supposed to work?

[anatoliy-balakirev]

Actually, just tried to replace javax.annotation.CheckForNull with org.checkerframework.checker.nullness.qual.Nullable in our code and that helped. Not sure if this is an expected behavior though. I thought old annotations are still supported as well...