title: how to name java hashmap local var in java language?
body: <p>as titled:</p>
  
  <p>how to name java hashmap local var  in java language?</p>
  
  <pre><code>private static volatile Map&lt;String, Session&gt; ip_Session_Map = new ConcurrentHashMap&lt;String, Session&gt;();
  </code></pre>
  
  <p>key is ip, value is session?</p>
  
  <p>how to name the map?</p>
  
  <p>ipSessionMap? ip_Session_Map? ipToSessionMap? or others? which is best?</p>