Posted by Oli Filth on 01/14/06 05:07

FluffyCat said the following on 14/01/2006 00:20:
> To add to my growing library of Design Patterns in PHP 5 I have
> written what I think is a good example of the Singleton Pattern.
>
> http://www.fluffycat.com/PHP-Design-Patterns/Singleton/
>

Unfortunately, this is not a good example of a singleton system.

You have a class (BookSingleton) with a public constructor, so there's
nothing to stop someone creating multiple BookSingleton objects with
multiple "new BookSingleton()" calls.

To solve this problem, you need to make the constructor private, and the
borrowBook() method static.


P.S. Another thing to make your code more readable would be to syntax
highlight it...


--
Oli

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