Finally block in Java - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of try-catch-finally with return

What is the output of this Java code?

Java

public class Test {
    public static int testMethod() {
        try {
            return 1;
        } catch (Exception e) {
            return 2;
        } finally {
            System.out.println("Finally block executed");
        }
    }
    public static void main(String[] args) {
        System.out.println(testMethod());
    }
}

A

1
Finally block executed

B

Finally block executed
1

C

Finally block executed
2

D

2
Finally block executed

💡 Hint

Remember that finally block runs even if there is a return in try.

The finally block runs before the method returns. So it prints first, then the return value is printed.

❓ Predict Output

intermediate

Finally block with exception thrown

What is the output of this Java code?

Java

public class Test {
    public static void main(String[] args) {
        try {
            throw new RuntimeException("Error");
        } finally {
            System.out.println("Finally block runs");
        }
    }
}

A

Finally block runs
Exception in thread "main" java.lang.RuntimeException: Error

B

Exception in thread "main" java.lang.RuntimeException: Error
Finally block runs

C Finally block runs

D No output

💡 Hint

Finally block runs even if exception is thrown.

The finally block executes before the exception is propagated, so its message prints first.

❓ Predict Output

advanced

Finally block overriding return value

What is the output of this Java code?

Java

public class Test {
    public static int test() {
        try {
            return 10;
        } finally {
            return 20;
        }
    }
    public static void main(String[] args) {
        System.out.println(test());
    }
}

A 10

B Compilation error

C Runtime exception

D 20

💡 Hint

Finally block return overrides try return.

If finally block has a return statement, it overrides any previous return.

❓ Predict Output

advanced

Finally block with exception and catch

What is the output of this Java code?

Java

public class Test {
    public static void main(String[] args) {
        try {
            int a = 5 / 0;
        } catch (ArithmeticException e) {
            System.out.println("Catch block");
        } finally {
            System.out.println("Finally block");
        }
    }
}

A Catch block

B

Finally block
Catch block

C

Catch block
Finally block

D Runtime exception

💡 Hint

Catch runs first, then finally.

Exception is caught, so catch block runs, then finally block runs.

🧠 Conceptual

expert

Finally block and System.exit() behavior

What happens when System.exit() is called inside a try block with a finally block present?

A Finally block does not execute, program exits immediately

B Finally block executes before program exits

C Program throws an exception before exiting

D Finally block executes only if System.exit() is called in catch

💡 Hint

System.exit() stops JVM immediately.

System.exit() terminates the JVM immediately, so finally block is skipped.

Practice

1.

What is the main purpose of the finally block in Java exception handling?

easy

A. To catch exceptions thrown in the try block

B. To throw new exceptions

C. To execute code regardless of whether an exception occurs or not

D. To declare exceptions that a method can throw

Solution

1. Step 1: Understand the role of try-catch-finally

   The try block contains code that might throw exceptions, catch handles them, and finally runs code after both.

2. Step 2: Identify the purpose of finally

   The finally block always executes, whether an exception occurs or not, to finalize or clean up resources.

3. Final Answer:

   To execute code regardless of whether an exception occurs or not -> Option C

4. Quick Check:

   finally always runs = B [OK]

Hint: finally always runs after try/catch blocks [OK]

Common Mistakes:

• Thinking finally only runs if an exception occurs
• Confusing finally with catch block
• Assuming finally can catch exceptions

2.

Which of the following is the correct syntax to add a finally block after a try-catch in Java?

try {
    // code
} catch(Exception e) {
    // handle
} ??? {
    // cleanup
}

easy

A. finally

B. end

C. finalize

D. final

Solution

1. Step 1: Recall Java exception syntax

   Java uses the keyword finally to define the block that runs after try and catch.

2. Step 2: Match the correct keyword

   Among options, only finally is the valid keyword for this block.

3. Final Answer:

   finally -> Option A

4. Quick Check:

   finally keyword syntax = D [OK]

Hint: finally keyword always spelled 'finally' [OK]

Common Mistakes:

• Using 'final' instead of 'finally'
• Confusing with 'finalize' method
• Using invalid keywords like 'end'

3.

What will be the output of the following Java code?

public class Test {
    public static void main(String[] args) {
        try {
            System.out.print("Try-");
            return;
        } catch(Exception e) {
            System.out.print("Catch-");
        } finally {
            System.out.print("Finally");
        }
        System.out.print("End");
    }
}

medium

A. Try-Catch-End

B. Try-Catch-Finally-End

C. Try-End

D. Try-Finally

Solution

1. Step 1: Analyze try block execution

   The try block prints "Try-" and then returns, so normally method would exit here.

2. Step 2: Check finally block behavior with return

   Even with return, finally block executes, printing "Finally" before method exits.

3. Step 3: Confirm code after finally

   Code after finally (System.out.print("End")) is unreachable due to return, so not executed.

4. Final Answer:

   Try-Finally -> Option D

5. Quick Check:

   finally runs even after return = C [OK]

Hint: finally runs even if try returns early [OK]

Common Mistakes:

• Assuming code after finally runs after return
• Thinking catch block runs without exception
• Ignoring finally block execution

4.

Identify the error in the following code snippet:

try {
    int a = 5 / 0;
} finally {
    System.out.println("Cleanup");
}

medium

A. No error, code is valid

B. finally block cannot be used without catch

C. Syntax error in try block

D. Missing catch block for exception

Solution

1. Step 1: Check try-finally syntax rules

   Java allows try-finally without catch; try must be followed by catch or/and finally.

2. Step 2: Analyze exception handling

   Division by zero throws ArithmeticException at runtime, finally executes cleanup, then exception propagates to caller.

3. Step 3: Confirm no error

   The code compiles and runs validly (prints "Cleanup" before propagating exception); no syntax or structural error.

4. Final Answer:

   No error, code is valid -> Option A

5. Quick Check:

   try-finally valid without catch = D [OK]

Hint: try-finally without catch is valid [OK]

Common Mistakes:

• Thinking finally requires catch block
• Confusing runtime exception with syntax error
• Believing finally alone causes compile error

5.

Consider this method:

public static int test() {
    try {
        System.out.print("Try-");
        throw new RuntimeException();
    } catch(RuntimeException e) {
        System.out.print("Catch-");
        return 1;
    } finally {
        System.out.print("Finally-");
        return 2;
    }
}

What will System.out.print(test()); output?

hard

A. Try-Catch-Finally-1

B. Try-Catch-Finally-2

C. Try-Finally-2

D. Catch-Finally-1

Solution

1. Step 1: Trace try block execution

   Try prints "Try-" then throws RuntimeException.

2. Step 2: Catch block handles exception

   Catch prints "Catch-" and returns 1, but return is not final yet.

3. Step 3: finally block overrides return

   Finally prints "Finally-" and returns 2, overriding previous return 1.

4. Step 4: Combine printed output and return value

   Printed output is "Try-Catch-Finally-" and method returns 2, so print(test()) outputs "2" after prints.

5. Final Answer:

   Try-Catch-Finally-2 -> Option B

6. Quick Check:

   finally return overrides catch return = A [OK]

Hint: finally return overrides other returns [OK]

Common Mistakes:

• Ignoring finally return overriding catch return
• Assuming catch return is final
• Missing printed output before return