[Java] False positive for Null Dereference

[Jiehong]

In java, Infer sometimes fails to see that null has been accounted for, depending on how nullity is checked for.

Information

• [x] The version of infer from infer --version: 1.1.0
• [x] Your operating system and version: using https://github.com/facebook/infer/blob/main/docker/1.1.0/Dockerfile
• [x] Which command you ran, for example infer -- make: infer run --fail-on-issue -- mvn compile
• [ ] The full output in a paste, for instance a gist.
• [x] If possible, a minimal example to reproduce your problem (for instance, some code where infer reports incorrectly, together with the way you run infer to reproduce the incorrect report).

Logs

error: Null Dereference
  object `futureResult` last assigned on line 53 could be null and is dereferenced at line 83.
  81.       } finally {
  82.         if (Objects.nonNull(futureResult)) {
  83. >         futureResult.cancel(true);
  84.         }
  85.         executor.shutdown();

Example to reproduce

Future variable = null;
if (Objects.nonNull(variable)) {
  variable.cancel(); // Infer thinks variable is null here
}

This seems to stem from Objects.nonNull(): Infer doesn't understand it, and only seem to understand x != null.

[Jiehong]

My guess is that most of null checks/requires functions from https://docs.oracle.com/javase/8/docs/api/java/util/Objects.html are not taken into account by Infer.