the following are also valid:
 <pre>
 restorerA1 = contextA_snapshot1.begin();
 restorerB1 = contextB_snapshot1.begin();
 ...
 restorerC1 = contextC_snapshot1.begin();
 ...
 restorerC1.endContext();
 ...
 restorerB2 = contextB_snapshot2.begin();
 restorerC2 = contextC_snapshot2.begin();
 ...
 restorerC2.endContext();
 restorerB2.endContext();
 ...
 restorerB1.endContext();
 restorerA1.endContext();
 </pre></div>
<dl>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="https://docs.oracle.co