title: Why does updateChilden with POJO work with Firebase Android SDK but not with Firebase Server SDK?
body: <p>Minimum example:</p>
  
  <pre><code>public class Post {
      public String id;
      public String name;
  }
  </code></pre>
  
  <p>On Android side I call:</p>
  
  <pre><code>Post post = new Post("some id", "some name");
  final Map&lt;String, Object&gt; updates = new HashMap&lt;&gt;();
  updates.put("posts/" + post.id, post);
  databaseReference.updateChildren(updates).addOnCompleteListener(listener);
  </code></pre>
  
  <p>and it works.
  But if I do the same thing on the Server (AppEngine Java Env) it fails with Exception:</p>
  
  <p><code>Failed to parse node with class class Post firebase</code></p>
  
  <p>It works when I do the <code>toMap()</code> workaround on the Server but why do I need that?
  It's just a simple POJO and it works on Android side...</p>
  
  <p>Edit: Don't worry about the id, it's just an exemplary value here. I use the actual ids from FireBase in both the App and the Server.</p>
  
  <p>Thanks</p>