Re: Multiple interfaces

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#250

From: Coho (Richard Swain)
Date: Sun, 23 Jun 2002 09:09

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It doesn't break encapsulation, you only have limited access to the 
Object and if your implementation is not declared public (i.e it has 
package scope) then you cannot get to it via casting down the interface. 
Thus you are limited to calling only methods on the public interfaces 
(which is good)

Rich

Tristan Reeves wrote:


[snip]


> Nothing, seeing that you can pass an interface reference to a method
> requiring an Object parameter (which I didn't know when I posted my lat
> message).
> eg If I have method myMethod(Object o), and an interface MyInterface, and a
> ref to a MyInterface (call it rMyInterface), then I can call
> myMethod(rMyInterface).
> 
> This is quite strange, because clearly MyInterface does not "extend" Object
> in any conventional way (this is true because you can't call Object methods
> from an interface reference), and yet once the interface has been passed to
> myMethod, it seems that I have access to the Object that is implementing the
> interface - this seems possible too by a straight typecast to Object.
> 
> Doesn't this break encapsulation??
> 
> Tristan.
> 
> 



-- 
http://www.krang.f9.co.uk

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Subject: Re: Multiple interfaces
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