False Negative: NullMarked Class must use Nullable for equals parameter

Rules and Languages Report False-positive / False-negative...
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1
  • SonarQube Community Build v25.10.0.114319
  • Java Code using JSpecify

I’m not sure which rule would be responsible to detect this issue. Maybe “java:S4449 Nullness of parameters should be guaranteed”?

If a NullMarked class overrides a method of a class that does not specify nullness, then method parameters cannot considered to be non-null. They should be annotated as Nullable or maybe NullUnmarked, IIUC.

The following code does not generate an issue:

package org.example;
import org.jspecify.annotations.NullMarked;

@NullMarked
public class OverrideEqualsNonNullParameter {
  @Override
  public boolean equals(Object obj) { // FN: parameter must be annotated as Nullable
    return super.equals(obj);
  }
  @Override
  public int hashCode() { 
    return super.hashCode();
  }
}

I’ve attached the above source as minimal maven project:

test.zip (1.9 KB)

Note, that the JSpecify’s Reference Checker detects this and outputs an error like

error: [nullness] Incompatible parameter type for object.
  public boolean equals(Object object) {
                               ^
  found   : Object
  required: Object?

Cheers
Andreas

3

Still reproducible with latest version v25.11.0.114957.

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