[java-dfa] IDEA-351380 Support @CheckForNull with @TypeQualifierNickname

GitOrigin-RevId: 7247332e3e0aba95116cb4d84696c00cfa20ba45

java/java-impl/src/com/intellij/codeInsight/annoPackages/Jsr305Support.java

@@ -16,6 +16,7 @@ import java.util.Set;
 public final class Jsr305Support implements AnnotationPackageSupport {
   public static final String JAVAX_ANNOTATION_NULLABLE = "javax.annotation.Nullable";
   public static final String JAVAX_ANNOTATION_NONNULL = "javax.annotation.Nonnull";
+  public static final String JAVAX_ANNOTATION_CHECK_FOR_NULL = "javax.annotation.CheckForNull";
   public static final String TYPE_QUALIFIER_NICKNAME = "javax.annotation.meta.TypeQualifierNickname";
 
   @Override
@@ -69,10 +70,18 @@ public final class Jsr305Support implements AnnotationPackageSupport {
    * @return nicknamed nullability declared by this annotation; null if this annotation is not a nullability nickname annotation
    */
   public static @Nullable Nullability getNickNamedNullability(@NotNull PsiClass psiClass) {
-    if (AnnotationUtil.findAnnotation(psiClass, TYPE_QUALIFIER_NICKNAME) == null) return null;
+    PsiModifierList modifierList = psiClass.getModifierList();
+    if (modifierList == null) return null;
+    if (!modifierList.hasAnnotation(TYPE_QUALIFIER_NICKNAME)) return null;
 
-    PsiAnnotation nonNull = AnnotationUtil.findAnnotation(psiClass, JAVAX_ANNOTATION_NONNULL);
-    return nonNull != null ? extractNullityFromWhenValue(nonNull) : null;
+    PsiAnnotation nonNull = modifierList.findAnnotation(JAVAX_ANNOTATION_NONNULL);
+    if (nonNull != null) {
+      return extractNullityFromWhenValue(nonNull);
+    }
+    if (modifierList.hasAnnotation(JAVAX_ANNOTATION_CHECK_FOR_NULL)) {
+      return Nullability.NULLABLE;
+    }
+    return null;
   }
 
   public static @Nullable Nullability extractNullityFromWhenValue(@NotNull PsiAnnotation nonNull) {
@@ -101,7 +110,7 @@ public final class Jsr305Support implements AnnotationPackageSupport {
   public @NotNull List<String> getNullabilityAnnotations(@NotNull Nullability nullability) {
     return switch (nullability) {
       case NOT_NULL -> Collections.singletonList(JAVAX_ANNOTATION_NONNULL);
-      case NULLABLE -> Arrays.asList(JAVAX_ANNOTATION_NULLABLE, "javax.annotation.CheckForNull");
+      case NULLABLE -> Arrays.asList(JAVAX_ANNOTATION_NULLABLE, JAVAX_ANNOTATION_CHECK_FOR_NULL);
       case UNKNOWN -> Collections.emptyList();
     };
   }

java/java-tests/testData/inspection/dataFlow/fixture/Jsr305CheckForNullAsQualifierNickname.java

@@ -0,0 +1,27 @@
+import static javax.annotation.meta.When.MAYBE;
+
+import javax.annotation.CheckForNull;
+import javax.annotation.Nonnull;
+import javax.annotation.meta.TypeQualifierNickname;
+
+class Main {
+  int go(Lib lib) {
+    return lib.usingNonnullMaybe().<warning descr="Method invocation 'hashCode' may produce 'NullPointerException'">hashCode</warning>() + lib.usingCheckForNull().<warning descr="Method invocation 'hashCode' may produce 'NullPointerException'">hashCode</warning>();
+  }
+
+  interface Lib {
+    @UsingNonnullMaybe
+    Object usingNonnullMaybe();
+
+    @UsingCheckForNull
+    Object usingCheckForNull();
+  }
+
+  @Nonnull(when = MAYBE)
+  @TypeQualifierNickname
+  @interface UsingNonnullMaybe {}
+
+  @CheckForNull
+  @TypeQualifierNickname
+  @interface UsingCheckForNull {}
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java

@@ -352,6 +352,12 @@ public class DataFlowInspectionTest extends DataFlowInspectionTestCase {
 
     doTest();
   }
+  
+  public void testJsr305CheckForNullAsQualifierNickname() {
+    addJavaxNullabilityAnnotations(myFixture);
+    addJavaxDefaultNullabilityAnnotations(myFixture);
+    doTest();
+  }
 
   public void testNullabilityDefaultVsMethodImplementing() {
     addJavaxDefaultNullabilityAnnotations(myFixture);
@@ -396,16 +402,24 @@ public class DataFlowInspectionTest extends DataFlowInspectionTestCase {
     fixture.addClass("package javax.annotation.meta;" +
                      "public enum When { ALWAYS, UNKNOWN, MAYBE, NEVER }");
 
-    fixture.addClass("package javax.annotation;" +
-                     "import javax.annotation.meta.*;" +
-                     "public @interface Nonnull {" +
-                     "  When when() default When.ALWAYS;" +
-                     "}");
-    fixture.addClass("package javax.annotation;" +
-                     "import javax.annotation.meta.*;" +
-                     "@TypeQualifierNickname " +
-                     "@Nonnull(when = When.UNKNOWN) " +
-                     "public @interface Nullable {}");
+    fixture.addClass("""
+                       package javax.annotation;
+                       import javax.annotation.meta.*;
+                       public @interface Nonnull {
+                         When when() default When.ALWAYS;
+                       }""");
+    fixture.addClass("""
+                       package javax.annotation;
+                       import javax.annotation.meta.*;
+                       @TypeQualifierNickname
+                       @Nonnull(when = When.MAYBE)
+                       public @interface CheckForNull {}""");
+    fixture.addClass("""
+                       package javax.annotation;
+                       import javax.annotation.meta.*;
+                       @TypeQualifierNickname
+                       @Nonnull(when = When.UNKNOWN)
+                       public @interface Nullable {}""");
   }
 
   public void testCustomTypeQualifierDefault() {