Given the class definitions: ``java class ImageScanner implements AutoCloseable { public void close () throws Exception { System.out.println ("Scanner closed."); } public void scanImage () throws…

Question

class ImageScanner implements AutoCloseable {
 public void close () throws Exception {
 System.out.println ("Scanner closed.");
 }
 public void scanImage () throws Exception {
 System.out.println ("Scan.");
 throw new Exception ("Unable to scan.");
 }
}

class ImagePrinter implements AutoCloseable {
 public void close () throws Exception {
 System.out.println ("Printer closed.");
 }
 public void printImage () {System.out.print ("Print.");}
}

try (
 ImageScanner ir = new ImageScanner();
 ImagePrinter iw = new ImagePrinter() ) {
 ir.scanImage();
 iw.printImage();
} catch (Exception e) {
 System.out.print (e.getMessage());
}

Options

• AScan.Printer closed.Scanner closed.Unable to scan.
• BScan.Print.Unable to scan.Printer closed.Scanner closed.
• CScan.Print.Printer closed.Scanner closed.Unable to scan.
• DCompilation fails

• A
  2% (1)
• B
  4% (2)
• C
  82% (40)
• D
  12% (6)

Explanation

There is actually an error in the stated correct answer. Based on Java's try-with-resources semantics, A is the correct answer, not C.

Here is why:

Why A is correct: ir.scanImage() prints "Scan." and then immediately throws an exception. Because the exception is thrown, the next statement iw.printImage() is never reached - execution exits the try block. Try-with-resources then automatically closes resources in reverse order of declaration: iw.close() fires first ("Printer closed."), then ir.close() ("Scanner closed."). Finally, the catch block prints "Unable to scan." (no newline, since it uses print not println).

Why the other options fail:

• B and C both show "Print." in the output, which requires iw.printImage() to execute - impossible since the exception from scanImage() aborts the try block before that line.
• B additionally puts the catch output before the resource closes, which contradicts the try-with-resources spec: resources always close before the catch body runs.
• D fails because the code is syntactically and semantically valid Java.

Memory tip: In try-with-resources, think "throw = emergency exit." The moment an exception is thrown in the try block, execution stops there, resources auto-close in reverse open-order (LIFO), and only then does the catch block run. "Close before catch, reverse of open."

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