 This constraint applies 
 in addition to any constraint entailed by primary key mapping and 
 to constraints specified at the table level.</div>
<dl>
<dt>Default:</dt>
<dd>false</dd>
</dl>
</li>
</ul>
</li>
</ul>
<ul class="blockList">
<li class="blockList"><a name="nullable--">
<!--   -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>nullable</h4>
<pre>public abstract&nbsp;boolean&nbsp;nullable</pre>
<div class="block">(Optional) Whether the database column is nullable.</div>
<dl>
<dt>Default:</d