Quick Answer
The answer is that the overriding method may throw FileNotFoundException, or any other subclass of IOException, or no exception at all. This is correct because Java’s rule for overriding method exception specifications requires that a subclass method cannot throw a broader checked exception than the parent method—it can only throw the same exception, a narrower (subclass) exception, or none. On the Oracle Java Foundations 1Z0-811 exam, this concept tests your understanding of polymorphism and exception handling, often appearing in questions that ask which throws clause is valid in an override. A common trap is assuming you can throw a broader exception like Exception, which is disallowed. To remember, think “narrower is allowed, broader is barred”—the overriding method’s exception must be a subtype of the parent’s exception, ensuring the caller’s catch blocks remain valid.
This 1Z0-811 practice question tests your understanding of object-oriented programming. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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.
A class 'Base' has a method 'public void display() throws IOException'. Subclass 'Derived' overrides display(). Which exception specifications are allowed in the overriding method?
public void display() throws SQLException
Why wrong: SQLException is unrelated checked exception, not allowed.
public void display() throws FileNotFoundException
FileNotFoundException is a subclass of IOException, allowed.
public void display() throws Exception
Why wrong: Exception is broader than IOException, not allowed.
public void display() throws Throwable
Why wrong: Throwable is broader than IOException, not allowed.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
public void display() throws FileNotFoundException
In Java, an overriding method can throw the same exception, a subclass of the exception thrown by the parent method, or no exception at all. The parent method throws IOException, so the overriding method may throw FileNotFoundException (a subclass of IOException). This follows the rule that the overriding method cannot throw a broader checked exception than the overridden method.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
public void display() throws SQLException
Why it's wrong here
SQLException is unrelated checked exception, not allowed.
public void display() throws FileNotFoundException
Why this is correct
FileNotFoundException is a subclass of IOException, allowed.
Related concept
Read the scenario before looking for a memorised answer.
public void display() throws Exception
Why it's wrong here
Exception is broader than IOException, not allowed.
public void display() throws Throwable
Why it's wrong here
Throwable is broader than IOException, not allowed.
Common exam traps
Oracle often tests the misconception that an overriding method can throw any exception, but the key is that only the same exception or a subclass of the parent's exception is allowed for checked exceptions.
Detailed technical explanation
This rule is enforced by the Java compiler to ensure polymorphism and substitutability (Liskov Substitution Principle). When a method is called through a reference of the parent type, the caller only expects exceptions declared in the parent method; a broader exception in the subclass would break that contract. In practice, this means developers must carefully design exception hierarchies to avoid forcing subclasses to catch or declare exceptions they cannot handle.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
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
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Object-Oriented Programming — study guide chapter
Learn the concepts, then practise the questions
Object-Oriented Programming practice questions
Targeted practice on this topic area only
All 1Z0-811 questions
509 questions across all exam domains
Oracle Java Foundations 1Z0-811 study guide
Full concept coverage aligned to exam objectives
1Z0-811 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise 1Z0-811 questions linked to What is Java.
Practise 1Z0-811 questions linked to Java Basics and Syntax.
Practise 1Z0-811 questions linked to Primitives, Strings and Operators.
Practise 1Z0-811 questions linked to Control Flow and Loops.
Practise 1Z0-811 questions linked to Arrays and Methods.
Practise 1Z0-811 questions linked to Object-Oriented Programming.
Practise 1Z0-811 questions linked to Exception Handling and Development Tools.
Practise 1Z0-811 questions linked to 1Z0-811 fundamentals.
Practise 1Z0-811 questions linked to 1Z0-811 scenario.
Practise 1Z0-811 questions linked to 1Z0-811 troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Object-Oriented Programming — This question tests Object-Oriented Programming — Read the scenario before looking for a memorised answer..
The correct answer is: public void display() throws FileNotFoundException — In Java, an overriding method can throw the same exception, a subclass of the exception thrown by the parent method, or no exception at all. The parent method throws IOException, so the overriding method may throw FileNotFoundException (a subclass of IOException). This follows the rule that the overriding method cannot throw a broader checked exception than the overridden method.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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 →
Keep practising
Last reviewed: Jun 30, 2026
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.
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.
Sign in to join the discussion.