title: Check if a List is a value in a HashMap
body: <p>I want to check if a value exists.</p>
  
  <p>My Code:</p>
  
  <pre><code>public static final Map&lt;String, List&lt;String&gt;&gt; m = new HashMap&lt;&gt;();
  
  if(m.containsValue("gummi")) {...}
  </code></pre>
  
  <p>My problem is that the value is a List.
  How can I check for the List?</p>