title: convert arrayList multimap to json string?
body: <p>I have the following code:</p>
  
  <pre><code>public static void postHttpStream(ArrayListMultimap&lt;String, String&gt; fcmbuildProperties){
      HttpClient client = new HttpClient();
      Gson gson = new Gson();
      System.out.println(fcmbuildProperties);
      String jsonString = gson.toJson(fcmbuildProperties);
      System.out.println(jsonString);
  }
  </code></pre>
  
  <p>where fcmbuildProperties is an ArrayListMultimap. I try to convert that to JSON here: <code>String jsonString = gson.toJson(fcmbuildProperties);</code>  But this returns an empty array.  What do I need to do instead?</p>
  
  <p>This is the input that fcmbuildProperties contain : <code>{build.name=[test_project], build.timestamp=[1425600727488], build.number=[121]}</code></p>
  
  <p>I need to convert this to Json. with key/values.</p>