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Old December 18th, 2003, 09:38 AM
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Default Simple Problem

I'm sure this is a really simple problem, but I'm quite new to Java and I can't figure it out, and am now having trouble thinking of a way of describing it...

OK say you have an application which is a book shop, in the main class file you launch from it it creates a new booklist instance to store all the books in the store.

But now then you want to do some work on this instance but from a different class which wasn't the once that called the construction, ie how can an instance be made global?

Hope this makes sense, I see there inheritance but does this provide access to the current instances/variables or just the methods?



Old December 19th, 2003, 11:56 AM
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Instantite an object of the type of class that you want to call and then pass to it's constructor, the reference of the new BookList.

// incomplete code snippet
BookList list = new BookList();
BookListUser = new BookListUser(list);


Old February 5th, 2004, 09:05 PM
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Your soloution of your problem depends on many things. Is the modifying object another (model)object, or a GUI object/class. The simplest way to do it is to have a class to that call the construction as you say, and that the same class sends your problem class ( maybe through the constructure ) to the working class. But maybe your problem can be solved through the MVC sofware pattern. Maybe you need an Observer? It's difficult to know with litle information

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