RE: Understanding Implements

[Buck Calabro <buck.calabro@xxxxxxxxxxxxxxxxx>]

John Taylor wrote:

>Sorry for the delay in responding. I've been knee-deep in an upgrade over
>the last few days, and I thought someone else would have picked up the ball
>by now.

I've seen your posts about your upgrade.  Glad to see you over the worst
spots!

>> So "interface" is really a way round the single 
>> inheritance restriction?
>>We can define "utility" classes that 
>>aren't really a subclass of anything else.
>> Without "interface" we'd be locked in to 
>>creating artificial objects to contain utility classes.
>>
>> Closer?

>Interfaces are not used to define utility classes because interfaces are
>_not_ classes. Remember, an interface is simply a collection of method
>_signatures_ (kind of like a procedure prototype in RPG). They describe a
>standard protocol for interacting with objects that implement the
interface.
>However, there is no source code within the methods defined in the
>interface. That code is the responsibility of whatever classes implement
it.
>Therefore, an interface may be created to define a certain set of
behaviours
>that a utility class _implements_, but the interface itself is not the
>utility class.

-snip-

>Is it getting any clearer?

Yes John, I think it is.  I'm quite a bit behind you folks on the learning
curve; probably because I can't deploy real world projects in Java here yet.
I'm still in the "think up a tool or personal project to work on" stage.  I
very much appreciate the theory and advice.

Buck
+---
| This is the JAVA/400 Mailing List!
| To submit a new message, send your mail to JAVA400-L@midrange.com.
| To subscribe to this list send email to JAVA400-L-SUB@midrange.com.
| To unsubscribe from this list send email to JAVA400-L-UNSUB@midrange.com.
| Questions should be directed to the list owner: joe@zappie.net
+---