Java AutoCloseable and Exception Handling Modifications
Short answer
BC Implement AutoCloseable in Folder class and override close() method.
Question
Key Takeaways
The question tests knowledge of interface implementation syntax and method overriding rules in Java, specifically regarding AutoCloseable.
This question tests the correct implementation of the AutoCloseable interface for try-with-resources usage. The correct modifications involve implementing the interface and overriding the close method to ensure the code compiles and prints 'Open Close'.
Common mistake: Learners often choose options that use 'extends' instead of 'implements' for interfaces or fail to override the close() method correctly, leading to compilation errors.
Expert Analysis
Why the Answer Is Correct
To enable the code to print 'Open Close', the Folder class must be compatible with the try-with-resources statement. This requires implementing the AutoCloseable interface (Option B: class Folder implements AutoCloseable). Additionally, since the base class or interface might define a close method, or simply to provide the specific behavior for printing 'Close', the close method must be overridden (Option C: public void close throws Exception { System.out.println("Close"); }). Option B correctly uses 'implements' because AutoCloseable is an interface. Option C provides the necessary implementation for the close logic.
Why the Other Options Are Wrong
Option A suggests using 'extends' with AutoCloseable, which is incorrect syntax as AutoCloseable is an interface, not a class. Option D likely involves incorrect method signature or access modifier issues (e.g., missing public or wrong exception type). Option E might fail to override the method correctly or have syntax errors. The community consensus confirms B and C are the correct pair.
Community Comment Notes
Multiple users confirmed that B and C are the correct answers. One user noted that 'implements' must be used for interfaces like AutoCloseable. Another user highlighted that overriding the close method is essential for the desired output.
Exam Strategy
Always check if a class is implementing an interface (use 'implements') or extending a class (use 'extends'). For try-with-resources, ensure the resource implements AutoCloseable and the close() method is properly defined.
Frequently Asked Questions
Why can't I use 'extends' for AutoCloseable?
What happens if I don't override close()?
Community Votes
100% of anonymous learners picked answer B. Votes are pick records left by other test-takers — they are not the verified answer.
Discussion 5 contributions
Compiled from public community threads and reader submissions, lightly edited for clarity. Handles and vote tallies are shown as recorded, and comments reflect the views of individual contributors.
From public community threads 5
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supersquax 👍 3B and C correct. A is wrong cuz both Closeable and AutoCloseable are "interfaces", not classes. Therefore, the "implements" keyword must be used. D wrong. the fact that it is "final" and doesnt throw anything is fine, but it is missing the "public" keyword. trying to compile without "public" gives this error: "attempting to assign weaker access privileges; was public"
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SrinivasJasti 👍 1 Answered BB & C are correct ---->The two key modifications that enable the code to print "Open Close" are: Implement AutoCloseable in the Folder class. Override the close() method in the Folder class.
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Tojose 👍 4options B and C
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zuluitai 👍 2B and C are correct.
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xplorerpj 👍 1 Answered BB & C are correct
Reader comments & corrections
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