"I never see what has been done; I only see what remains to be done."
- Marie Curie
3.
public class ExceptionTest
{
class TestException extends Exception {}
public void runTest() throws TestException {}
public void test() /* Point X */
{
runTest();
}
}
At Point X on line 5, which code is necessary to make the code compile?
[A].
No code is necessary.
[B].
throws Exception
[C].
catch ( Exception e )
[D].
throws RuntimeException
Answer: Option E
Explanation:
Option B is correct. This works because it DOES throw an exception if an error occurs.
Option A is wrong. If you compile the code as given the compiler will complain:
"unreported exception must be caught or declared to be thrown" The class extends Exception so we are forced to test for exceptions.
Option C is wrong. The catch statement belongs in a method body not a method specification.
Option D is wrong. TestException is a subclass of Exception therefore the test method, in this example, must throw TestException or some other class further up the Exception tree. Throwing RuntimeException is just not on as this belongs in the java.lang.RuntimeException branch (it is not a superclass of TestException). The compiler complains with the same error as in A above.
Whenever we call any method that is throwing any exception we have two options:
either surround the calling method with try-catch block or throws exception.
