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All the overriden equals!

Marcela Blei
Ranch Hand

Joined: Jun 28, 2000
Posts: 477
Is there any equals method in all the API specification that throws an exception when you pass to it an object that isn�t an instanceof the type object that the equals belongs to.
Eg.

I began to read the API doc by it�s index and I didn�t find any exception thrown so, because it�s a tedius job, perhaps someone know a special case when this happens.
Thanks.

Ajith Kallambella
Sheriff

Joined: Mar 17, 2000
Posts: 5782
Marcela,
No need to work that hard. Use rules of overriding.
Since the method on the Object is not declared to be throwing any exceptions, even the overridden versions cannot!
Ajith


Open Group Certified Distinguished IT Architect. Open Group Certified Master IT Architect. Sun Certified Architect (SCEA).
Marcela Blei
Ranch Hand

Joined: Jun 28, 2000
Posts: 477
But they can throw a ClassCastException that is a Runtime Exception if the implemented equals try to cast the object argument directly without using the instanceof operator before.

[This message has been edited by Marcela Blei (edited August 01, 2000).]
Ajith Kallambella
Sheriff

Joined: Mar 17, 2000
Posts: 5782
Marcela,
It is not necessary to declare RuntimeException and its subclasses in the method signature. They can be ( and usually ) are thrown without declaring them. Hence they don't appear as a part of method signature in the API documentation.
Ajith
Marcela Blei
Ranch Hand

Joined: Jun 28, 2000
Posts: 477
Sorry, my question wasn�t clear. Suppose the following question:
What�s the result of compiling and executing the following code:

a) It prints false and throws a ClassCastException
b) It throws a ClassCastException
c) It prints false false
thomas
Ranch Hand

Joined: May 26, 2002
Posts: 79
As far as I can see, the equals() methods in the API simply return false if the objects are unrelated. They do not throw an exception.
 
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