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<h1>Refactoring Class Hierarchy</h1>
<p>db4o does not directly support the following two
refactorings: </p>
<ul>
<li>Inserting
classes into an inheritance hierarchy. </li>
<li>Removing
class from inheritance hierarchies.</li>
</ul>
<p>For example:</p>
<p><code>class A</code> </p>
<p><code>class B : A</code> </p>
<p><code>class C : B</code></p>
<ol>
<li>A
new Class D can not be introduced above C. </li>
<li>Classes
A and B can not be removed.<br></li>
</ol>
<p>The only current possible solution for the above
refactorings is a workaround:</p>
<ol>
<li>Create
the new hierarchy with different names, preferably in a new package.
</li>
<li>Copy
all values from the old classes to the new classes. </li>
<li>Redirect
all links from existing objects to the new classes.</li>
</ol>
<p><div class="childTopicList">More Reading:<ul>
<li><p><a href="refactoring_class_hierarchy/removing_class_from_a_hierarchy.html" class="wikiLink">Removing Class From A Hierarchy</a></p></li>
<li><p><a href="refactoring_class_hierarchy/inserting_class_into_a_hierarchy.html" class="wikiLink">Inserting Class Into A Hierarchy</a></p></li>
<li><p><a href="refactoring_class_hierarchy/a.html" class="wikiLink">A</a></p></li>
<li><p><a href="refactoring_class_hierarchy/b.html" class="wikiLink">B</a></p></li>
<li><p><a href="refactoring_class_hierarchy/c.html" class="wikiLink">C</a></p></li>
</ul></div>
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This revision (2) was last Modified 2007-09-30T18:22:10 by Tetyana.
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