title: Java Dictionary value of type tuple
body: <p>I want a Dictionary (HashTable, Map, ...) that has one key and several values.</p>
  
  <p>I.e. I want something like </p>
  
  <p><code>HashTable&lt;Key, [value1, value2]&gt;</code></p>
  
  <p>How do I get this?</p>