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<h1>Refactoring Class Hierarchy</h1>
<p>db4o does not directly support the following two
refactorings: </p>
<ul>
<li value="1">Inserting
classes into an inheritance hierarchy. </li>
<li value="2">Removing
classes from inheritance hierarchy.</li>
</ul>
<p>Note that interfaces don't influence the inheritance-hierarchy and can be added and removed at any time.</p>
<p>For example we've following classes:</p>
<p>
<img src="inheritance-refactoring.png" />
</p>
<p> </p>
<p>In this example you cannot introduce a 'Animal' class above the 'Mammal' or add another class between 'Mammal' and 'Primate'. Also you shouldn't remove an class form the inheritance-hierarchy.</p>
<p>Currently the only possible solution for this refactoring is this.</p>
<ol>
<li value="1">Create
the new hierarchy with different names, preferably in a new package</li>
<li value="2">Copy
all values from the old classes to the new classes.</li>
<li value="3">Redirect
all references from existing objects to the new classes.</li>
</ol>
<p>Take a look at the example to how to add a class into the hierarchy. <a href="refactoring_class_hierarchy/inserting_class_into_a_hierarchy.htm" target="" title="" alt="" class="MCXref" xrefformat="See "{paratext}"">See "Inserting Class Into A Hierarchy"</a>. </p>
<p>Or how you can remove a class from the inheritance hierarchy. <a href="refactoring_class_hierarchy/removing_class_from_a_hierarchy.htm" target="" title="" alt="" class="MCXref" xrefformat="See "{paratext}"">See "Removing Class From A Hierarchy"</a></p>
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