8291734: Return accurate ACC_SUPER access flag for classes

Reviewed-by: mchung

src/java.base/share/classes/java/lang/Class.java

@@ -1346,16 +1346,18 @@ public final class Class<T> implements java.io.Serializable,
      * @since 20
      */
     public Set<AccessFlag> accessFlags() {
-        // This likely needs some refinement. Exploration of hidden
-        // classes, array classes.  Location.CLASS allows SUPER and
-        // AccessFlag.MODULE which INNER_CLASS forbids. INNER_CLASS
-        // allows PRIVATE, PROTECTED, and STATIC, which are not
-        // allowed on Location.CLASS.
-        return AccessFlag.maskToAccessFlags(getModifiers(),
-                                            (isMemberClass() || isLocalClass() ||
-                                             isAnonymousClass() || isArray()) ?
-                                            AccessFlag.Location.INNER_CLASS :
-                                            AccessFlag.Location.CLASS);
+        // Location.CLASS allows SUPER and AccessFlag.MODULE which
+        // INNER_CLASS forbids. INNER_CLASS allows PRIVATE, PROTECTED,
+        // and STATIC, which are not allowed on Location.CLASS.
+        // Use getClassAccessFlagsRaw to expose SUPER status.
+        var location = (isMemberClass() || isLocalClass() ||
+                        isAnonymousClass() || isArray()) ?
+            AccessFlag.Location.INNER_CLASS :
+            AccessFlag.Location.CLASS;
+        return AccessFlag.maskToAccessFlags((location == AccessFlag.Location.CLASS) ?
+                                            getClassAccessFlagsRaw() :
+                                            getModifiers(),
+                                            location);
     }
 
     /**

test/jdk/java/lang/reflect/AccessFlag/ClassAccessFlagTest.java

@@ -23,7 +23,7 @@
 
 /*
  * @test
- * @bug 8266670
+ * @bug 8266670 8291734
  * @summary Test expected AccessFlag's on classes.
  */
 
@@ -46,16 +46,11 @@ import java.util.*;
  * return the Class object created from a module-info.class
  * file. Therefore, this test does not attempt to probe the setting of
  * that access flag.
- *
- * For a class, the VM must treat the class as if the ACC_SUPER bit
- * were set, but that bit is cleared by HotSpot when it is passed out
- * to the core reflection libraries. Therefore, this test does not
- * attempt to check whether or not AccessFlag.SUPER is set.
  */
-@ExpectedClassFlags("[PUBLIC, FINAL]")
+@ExpectedClassFlags("[PUBLIC, FINAL, SUPER]")
 public final class ClassAccessFlagTest {
     public static void main(String... args) {
-        // Top-level and axuillary classes; i.e. non-inner classes
+        // Top-level and auxiliary classes; i.e. non-inner classes
         Class<?>[] testClasses = {
             ClassAccessFlagTest.class,
             TestInterface.class,
@@ -226,7 +221,7 @@ public final class ClassAccessFlagTest {
 interface TestInterface {}
 
 
-@ExpectedClassFlags("[FINAL, ENUM]")
+@ExpectedClassFlags("[FINAL, SUPER, ENUM]")
 enum TestOuterEnum {
     INSTANCE;
 }