title: Keeping POJO intact how to inject new field in JSON using Jackson?
body: <p>My ultimate aim is, I have <strong>list of POJO</strong>. I need to convert as a <strong>JSON String</strong> using Jackson. While converting as JSON. I need to add few more keys.
  In order to do that, I have only solution. If I convert as <strong>list of POJO</strong> into <strong>list of ObjectNode</strong> so that I can add info in <strong>ObjectNode</strong>. After that I will convert as <strong>JSON String</strong>.</p>
  <p><code>List&lt;dummyPOJO&gt; dummyPOJO = getPOJO();</code>
  <code>ObjectNode objectNode = mapper.convertValue(dummyPOJO, new TypeReference&lt;ArrayList&lt;ObjectNode&gt;&gt;(){});</code></p>
  <p>This code is giving an follow error</p>
  <p><code>java.lang.ClassCastException: java.util.ArrayList cannot be cast to com.fasterxml.jackson.databind.node.ObjectNode</code></p>
  <p>Please let me know if any solution available. Thanks in Advance :)</p>