False positive on java:S2259 with @Nullable generics parameter

SonarQube for IDE IntelliJ Platform
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1

We get a “Nullpointers should not be dereferenced” (S2259) message on the following example code:

import java.util.*;
import org.jetbrains.annotations.*;

public class RuleJavaS2259
{
	public static void main( final String[] args ) {
		example( List.of() );
	}

	static void example( final @NotNull List<@Nullable Object> list ) {
		System.out.println( list.size() );
	}
}

In the above code list cannot be null, but elements inside the list can, this is specified by the annotations.

It appears that the @Nullable annotation is considered to apply to list instead of the generic parameter (that indicates that the list may contain nulls).

If I remove all annotations, the rule is not triggered. If I remove only the @NotNull, the rule is still (falsely) triggered.

Environment:

  • Java: JetBrains s.r.o. 21.0.3
  • OS: Mac OS X x86_64
  • IDE: IntelliJ IDEA 2024.3
  • SonarLint: 10.13.1.80133