Question 166 of 509
Object-Oriented ProgramminghardMultiple ChoiceObjective-mapped

Quick Answer

The answer is that Circle must override draw(). This is correct because when a concrete class extends an abstract class, it is required to implement all abstract methods inherited from that parent; here, Circle provides an empty body for draw(), which fulfills the abstract class method implementation requirement. On the Oracle Java Foundations 1Z0-811 exam, this concept tests your understanding of inheritance and polymorphism, specifically that a non-abstract subclass cannot leave any abstract method unimplemented—a common trap is thinking an empty body doesn't count as an override, but it does. Remember the rule: if a class is not abstract, it must complete every abstract method it inherits, or the code will not compile. A helpful memory tip is to think of abstract methods as contracts: a concrete subclass must sign every dotted line.

1Z0-811 Object-Oriented Programming Practice Question

This 1Z0-811 practice question tests your understanding of object-oriented programming. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.

Given: abstract class Shape { abstract void draw(); } class Circle extends Shape { void draw() {} } Which is true?

Question 1hardmultiple choice
Full question →

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

Circle must override draw()

Option B is correct because Circle is a concrete class that extends the abstract class Shape, which declares the abstract method draw(). A concrete subclass of an abstract class must provide an implementation for all inherited abstract methods, unless the subclass is also declared abstract. Circle provides an implementation of draw() with an empty body, which satisfies the override requirement.

Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

  • Shape cannot have a constructor

    Why it's wrong here

    Abstract classes can have constructors, invoked via super().

  • Circle must override draw()

    Why this is correct

    Circle provides implementation; it compiles fine.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Shape s = new Shape(); is valid

    Why it's wrong here

    Cannot instantiate abstract classes.

  • draw() must be public in Circle

    Why it's wrong here

    The overriding method can have the same or broader access; not necessarily public.

Common exam traps

Common exam trap: answer the scenario, not the keyword

The trap here is that candidates often think abstract classes cannot have constructors (option A) or that overriding methods must always be public (option D), but the Java specification allows constructors in abstract classes and only requires the overriding method to have at least the same access level as the abstract method.

Detailed technical explanation

How to think about this question

In Java, an abstract class is a class declared with the abstract keyword that may contain abstract methods (methods without a body). When a concrete class extends an abstract class, the compiler enforces that all abstract methods are implemented; failure to do so results in a compilation error. The access modifier of the overriding method must be the same or more permissive (e.g., default can be overridden by default, protected, or public), but not more restrictive. This design allows abstract classes to define a contract for subclasses while still providing shared implementation via constructors and concrete methods.

KKey Concepts to Remember

  • Read the scenario before looking for a memorised answer.
  • Find the constraint that changes the correct option.
  • Eliminate answers that are true in general but not in this case.

TExam Day Tips

  • Watch for words such as best, first, most likely and least administrative effort.
  • Review why wrong options are wrong, not only why the correct option is correct.

Key takeaway

Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.

Real-world example

How this comes up in practice

A practitioner preparing for the 1Z0-811 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.

What to study next

Got this wrong? Here's your next step.

Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.

Related practice questions

Related 1Z0-811 practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

Practice this exam

Start a free 1Z0-811 practice session

Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.

FAQ

Questions learners often ask

What does this 1Z0-811 question test?

Object-Oriented Programming — This question tests Object-Oriented Programming — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: Circle must override draw() — Option B is correct because Circle is a concrete class that extends the abstract class Shape, which declares the abstract method draw(). A concrete subclass of an abstract class must provide an implementation for all inherited abstract methods, unless the subclass is also declared abstract. Circle provides an implementation of draw() with an empty body, which satisfies the override requirement.

What should I do if I get this 1Z0-811 question wrong?

Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.

What is the key concept behind this question?

Read the scenario before looking for a memorised answer.

About these practice questions

Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →

How Courseiva writes practice questions · Editorial policy

Same concept, more angles

1 more ways this is tested on 1Z0-811

These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.

Variation 1. A developer creates an interface 'Drawable' with a single abstract method 'draw()'. They then create a class 'Circle' that implements Drawable but forgets to provide the draw() method. Circle is not declared abstract. What will happen when compiling Circle?

hard
  • A.Compilation fails because interfaces cannot be implemented without overriding all methods
  • B.Compilation succeeds, a default empty method is generated
  • C.Compilation fails because Circle must either implement draw() or be declared abstract
  • D.Compilation succeeds but a warning is issued

Why C: A class that implements an interface must provide implementations for all abstract methods, or it must be declared abstract. Without the implementation and without being abstract, the class does not compile.

Last reviewed: Jun 11, 2026

Question Discussion

Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.

Loading comments…

Sign in to join the discussion.

This 1Z0-811 practice question is part of Courseiva's free Oracle certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 1Z0-811 exam.