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PO1:n relation in OOP regarding to deserialisation
 

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  1. PO1:n relation in OOP regarding to deserialisation
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    <p>I've modeled two classes like this:</p> <pre><code>ClassA -- n:1 --&gt; ClassB </code></pre> <p>ClassB knows nothing about ClassA (unidirectional relation). Now I'm currently writing a file loader for ClassA that <em>uses</em> (and does <em>not own</em>) a ClassB object.</p> <p>Code-wise ClassA holds a pointer to ClassB, and that is where my problem arises: The loader is responsible for loading ClassA only and doesn't have access to the container that contains all the ClassB objects, so it's not possible to establish the relation.</p> <p>A solution would be to insert a string member to ClassA that contains the id of the ClassB object, so the relation can be established later. The question is, however, if there are any other approaches that solve this problem. I don't need the id after loading anymore, therefore I'd like to leave it out.</p> <p><strong>Example of a ClassA file that shall be loaded:</strong></p> <pre><code>Id: "some-id" # Irrelevant for this example. ;-) ClassB: "some-classb-id" </code></pre> <p>ClassA holds <strong>one</strong> pointer to a ClassB object. The loader now deserialises ClassA and does <strong>not</strong> load any ClassB objects, instead only a relation is about to be established to an already <strong>existing</strong> ClassB object. The reason for this is that ClassB objects are pre-loaded and ClassA objects can be added during runtime.</p> <p>The ClassB pointer in ClassA <em>may be NULL</em>, that's completely okay (it's an optional relation).</p>
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    1. USstschindler
    1. USstschindler
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    1. COI don't know much about your problem, so your paragraph is kind of confusing about what you want. ClassB knows nothing about A, okay, no problem. The File Loader knows about ClassA but not ClassB; okay, I don't know why that really matters, as why can't it? But again, I don't know anything about the specifics of your problem. ClassA holds a single pointer to a ClassB? Pointer can be NULL, but when does the relation get set? If it's a list of ClassB, then it just remains empty until later. Where is the string identifying ClassB come from? Why can't you establish the pointer then?
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      1. USleetNightshade
    2. CO@Tank Again, please just clarify the problem, I can't really make out what you want or what you're trying to do exactly.
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      1. USleetNightshade
    3. CO@leetNightshade: I updated the question. Hope this clarifies the problem more.
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      1. USstschindler
 

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