title: How to increment a value, given a key in a java hashmap?
body: <p>If I have the following:</p>
  
  <pre><code>public enum Attribute {
       ONE, TWO, THREE
  }
  
  private Map&lt;String, Integer&gt; mAttributesMap = new HashMap&lt;&gt;();
  
  mAttributesMap.put(Attribute.ONE.name(), 5);
  mAttributesMap.put(Attribute.TWO.name(), 5);
  </code></pre>
  
  <p>So how can I get the key of <code>mAttibutesMap</code>? And how to increment it?</p>