title: When should I use a Hashtable versus a HashMap
body: <p><s>This is not a question about the differences between <code>Hashtable</code> and <code>HashMap</code>.</s> I understand that a <code>Hashtable</code> object cannot accept <code>null</code> values for either key or value entries, that it is synchronized collection, and that it uses slightly less memory than a <code>HashMap</code>.</p>
  
  <p>I'm wondering about the scenarios where it would be more appropriate to use a <code>Hashtable</code> instead of a <code>HashMap</code>.</p>