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<h2 class="title" style="clear: both"><a id="dpl_replace"></a>Replacing Entity Objects</h2>
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<p>
To modify a stored entity object, retrieve it, update
it, then put it back to the entity store:
</p>
<pre class="programlisting">
SimpleEntityClass sec = sda.pIdx.get("keyone");
sec.setSKey("skeyoneupdated");
sda.pIdx.put(sec);
</pre>
<p>
Note that because we updated a field on the object that is
a secondary key, this object will now be accessible by the
secondary key of <code class="literal">skeyoneupdated</code> instead
of the previous value, which was <code class="literal">skeyone</code>
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<p>
Be aware that if you modify the object's primary key, the behavior is
somewhat different. In this case, you cause a new instance
of the object to be created in the store, instead of
replacing an existing instance:
</p>
<pre class="programlisting">// Results in two objects in the store. One with a
// primary index of "keyfive" and the other with primary index of
//'keyfivenew'.
SimpleEntityClass sec = sda.pIdx.get("keyfive");
sec.setPKey("keyfivenew");
sda.pIdx.put(sec); </pre>
<p>
Finally, if you are iterating over a collection of objects
using an <code class="classname">EntityCursor</code>, you can
update each object in turn using
<code class="methodname">EntityCursor.update()</code>. Note,
however, that you must be iterating using a
<code class="classname">PrimaryIndex</code>; this operation is not
allowed if you are using a
<code class="classname">SecondaryIndex</code>.
</p>
<p>
For example, the following iterates over every
<code class="classname">SimpleEntityClass</code> object in the entity
store, and it changes them all so that they have a
secondary index of <code class="literal">updatedskey</code>:
</p>
<pre class="programlisting">EntityCursor<SimpleEntityClass> sec_pcursor = sda.pIdx.entities();
for (SimpleEntityClass sec : sec_pcursor) {
sec.setSKey("updatedskey");
sec_pcursor.update(item);
}
sec_pcursor.close(); </pre>
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