title: Retrofit2 error java.io.EOFException: End of input at line 1 column 1
body: <p>I called <strong>PATCH</strong> web service  using Retrofit2 but <strong>onResponse</strong> is not called and the <strong>onFailure</strong> is called <strong>Despite of</strong> the operation of the service is succeeded on the server side <strong>perfectly</strong>  </p>
  
  <p>And whenever,I tried to use fiddler to check the service its working , i found the problem is that serializing the coming response of the service and when using fiddler i found that no content of the JSON response so the Retrofit service assumed that its failed because there is no content and it cannot serialize the EMPTY content 
  and give me this error</p>
  
  <pre><code>java.io.EOFException: End of input at line 1 column 1
  </code></pre>
  
  <p><strong>Fiddler raw Response</strong></p>
  
  <pre><code>HTTP/1.1 200 OK
  Server: nginx/1.9.4
  Date: Wed, 02 Mar 2016 09:55:55 GMT
  Content-Type: application/json
  Content-Length: 0
  Connection: close
  Status: 200 OK
  X-Content-Type-Options: nosniff
  </code></pre>
  
  <p><strong>Fiddler Json Response is empty</strong></p>
  
  <p><strong>webservice in java</strong></p>
  
  <pre><code>Call&lt;Object&gt; call = TimeCapp.services.accept_invited_alerts(HomeActivity.api_token, alert_id);
  
  call.enqueue(new Callback&lt;Object&gt;()
  {
      @Override
      public void onResponse (Call&lt;Object&gt; call, Response&lt;Object&gt; response)
      {
          if (response.isSuccess()) {
              String x = response.body();
          }
      }
      @Override
      public void onFailure (Call&lt;Object&gt;call, Throwable t)
      {
          String x = t.getMessage();//java.io.EOFException: End of input at line 1 column 1
      }
  }
  </code></pre>
  
  <p>I tried to replace <strong>object</strong> with String,JsonObject,emptyCalssBody .... but its failed </p>
  
  <p><strong>the interface of the webservice</strong></p>
  
  <pre><code>@PATCH("alerts/{alert_id}/accept")
  Call&lt;Object&gt; accept_invited_alerts(@Header("X-Api-Token") String  
  api_token, @Path("alert_id") int alert_id);
  </code></pre>