Exam Cram Question

[Sathi Chowdhury]

Hi & Good Morning,

Exam Cram has a question :
Exception
+-----BadTastException
+--------BitterException
+--------SourException
BadTaste Exception is defined as an abstract class.
You have a method eatMe that may throw a BitterException or a SourException.Which of the following declaration will be acceptable to the compiler?
a) public void eatMe(Ingredient[] list) throws
BadTasteException
b) public void eatMe(Ingredient[] list) throws
BitterException,SourException
c) public void eatMe(Ingredient[] list) may throw
BadTesteException
d) public void eatMe(Ingredient[] list)

the answer is given a) & b)
I thought it should be only b).
can an abstract exception be thrown?
can any of u pls help me in getting out of this doubt.
thanks & regards
Sathi

[Brett Delia]

Yes the answer a is legal.
You're not throwing an abstract exception. You are throwing an exception of type BadTasteException, which you can not instantiate an object of, but you can instantiated objects of types BitterException and SourException which are subclasses of BadTasteException. It is perfectly legal to declare a method throws a parent class (abstract or not), but the only practical types thrown from it are actually subclasses of the parent class.
Hope this helps.

[Sathi Chowdhury]

thanks Brett.

[William Brogden]

I might add that understanding how you might treat the same object with a reference to an interface, an abstract class or a parent object is ABSOLUTELY ESSENTIAL to programming in Java.
As I recall, checking for this understanding is one reason I wrote that question in the first place.
Bill

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