title: Jackson JSON: Serialize Array of Objects as their parent type
body: <p>I'm serializing an array of objects of different types, but all of which are of supertype <code>BasicClass</code>. When I serialize it as such:</p>
  
  <pre><code>@JsonProperty
  public BasicClass[] getReferences() {
      return this.refs;
  }
  </code></pre>
  
  <p>it also serializes all the subtype JSON properties. How can I make it only serialize the supertype properties?</p>