All the overriden equals!

[Marcela Blei]

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.

    Long l = new Long(1);
    Integer i = new Integer(1);
    i.equals(l) //This returns false, I expected an exception

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]

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

[Marcela Blei]

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]

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]

Sorry, my question wasn�t clear. Suppose the following question:
What�s the result of compiling and executing the following code:

1  Dimension dim = new Dimension();
2  Color col = new Color(Color.pink); 
3  System.out.print(col.equals(dim));
4  System.out.print(dim.equals(col));

a) It prints false and throws a ClassCastException
b) It throws a ClassCastException
c) It prints false false

[thomas]

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.