le class="table table-bordered params"><tr><th style="width:25%;"><code>oldKey</code></th><td><p>A mapped key that will be unmapped.</p></td></tr><tr><th style="width:25%;"><code>newKey</code></th><td><p>An unmapped key to map to.</p></td></tr></table><p class="javadoc">Returns:</p><div class="indent inline-content"><p>The <code><a href="../../nb/ds/NamedData.html#NamedData">NamedData</a>&lt;T&gt;</code> that had its mapping changed, <code>null</code> if <code>oldKey</code> wasn't mapped.</p></div></div></d