``java public class X { protected void print(Object obj) { print(objects); } public final void print(Object... objects) { collection.forEach(System.out::println); } } public class Y extends X {…

Question

public class X {
 protected void print(Object obj) {
 print(objects);
 }
 public final void print(Object... objects) {
 collection.forEach(System.out::println);
 }
}

public class Y extends X {
 public void print(Object obj) {
 System.out.println("obj " + obj);
 }
 public void print(Object... objects) {
 for (Object object : objects) {
 System.out.println("[" + object + "]");
 }
 }
 public void print(Collection collection) {
 print(collection.toArray());
 }
}

Options

• AThe method X.print(Object) does not call the method super.print(Object)
• BThe method X.print(Object...) is not accessible to Y
• CThe method Y.print (collection), however. Out of scope, is an invalid Java identifier.
• DThe method print (Object) and the method print (Object...) are duplicates of each other. The method X.print (Object...) cannot override the final method X.print (Object...)

• A
  13% (2)
• B
  6% (1)
• C
  6% (1)
• D
  75% (12)

Explanation

Option D is correct because Y.print(Object... objects) attempts to override X.print(Object... objects), but that method is declared final in class X - Java prohibits overriding final methods, so the compiler rejects class Y entirely. The first half of option D ("duplicates of each other") is a red herring phrasing; the decisive issue is the final violation, not duplication.

Why the distractors are wrong:

• A is wrong because there is no rule requiring a method to call super; omitting a super call is valid and not a compilation error.
• B is wrong because X.print(Object...) is declared public, making it fully accessible to any subclass including Y.
• C is wrong because collection is a perfectly valid Java identifier; the sentence itself is grammatically nonsensical and describes no real Java rule.

Memory tip: Think of final on a method as "the last word" - no subclass can have the final word on that method. Whenever you see a subclass redefine a method that a parent marked final, that's an instant compile error, regardless of access modifiers or parameter types.

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