title: Gson deserializg single object
body: <p>I have json object: </p>
  
  <pre><code>{
      user:
      {
          id: 1
          avatar_url: "default.png"
          first_name: "Example"
          last_name: "User"
          email: "user@example.com"
      }
  }
  </code></pre>
  
  <p>and how can I deserialize this object by GSON having only class:</p>
  
  <pre><code>public class User {
      public long id;
      public String avatar_url;
      public String first_name;
      public String last_name;
      public String email;
  }
  </code></pre>
  
  <p>Is it possible NOT creating new class ?</p>