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<h1>Transparent Activation Pitfalls</h1>
<p><a href="../transparent_activation_framework.htm">Transparent Activation</a> is a powerful feature that can
make development much faster, easier and error-proof. But as any power it can
lead to trouble if used in a wrong way. The aim of this chapter is to point you
out to typical pitfalls, which can lead to unexpected and undesired results.</p>
<h2>Not Activate Call Before Field Access</h2>
<p>Before accessing any field you need to call the activate-method. This is true for all <span class="Primarygetter/setter">property</span> and also for other methods like the to string method or the hash code method. The best strategy is to call the activate-method in the <span class="Primarygetter/setter">property</span> and then access the field through those even in the class itself.</p>
<p>Or use the <a href="../../../advanced_topics/enhancement_tools.htm">enhancement-tools</a> to avoid this issue complete. </p>
<h2>Migrating Between Databases</h2>
<h3>Problem</h3>
<p>Transparent <span class="MCPopup"><a href="javascript:void(0);" class="MCPopupSpot" onclick="FMCPopup( event, this ); return false;" MadCap:src="../../activation.htm">Activation<img style="border: none;margin-left: 5px;" src="../../../SkinSupport/ExpandingClosed.gif" MadCap:altsrc="../../../SkinSupport/ExpandingOpen.gif" class="MCExpandingIcon" onload="if ( typeof( FMCPreloadImage ) == 'function' ) { FMCPreloadImage( '../../../SkinSupport/ExpandingOpen.gif' ); }" /></a></span> is implemented through <code>Activatable/IActivatable</code> interface, which binds an object to the current object container. In a case when an object is stored to more than one object container, this logic won't work, as only one binding (activator) is allowed per object. </p>
<h3>Solution</h3>
<p>To allow correct behavior of the object between databases, the object should be unbinded before being stored to the next database. This can be done with the following code:</p>
<p MadCap:conditions="Global.Primary:java" />
<p MadCap:conditions="Primary..NET">
<p>.NET: </p>
<p><code>myObject.Bind(null);</code>
</p>
</p>
<p MadCap:conditions="Global.Primary:net" />
<p>For more information see an <a href="transparent_activation/migrating_between_databases.htm">example</a>. </p>
<h2>Debugging Instrumented Classes</h2>
<p>Debugging instrumented classes may not work 100% correct. <span>Make sure you use the debug-flag for the <a href="../../../advanced_topics/enhancement_tools/enhancement_for_.net/db4otool.htm">db4otool</a></span></p>
<p>You should be able to debug normally anywhere around
instrumented bytecode. If you still think that the problem occurs in the
instrumented area, please submit a bug report to <a href="http://tracker.db4o.com/">db4o Jira</a>.</p>
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