title: Integer can not be cast to JsonNode
body: <p>i got a cast error and have no idea how to solve that. </p>
  
  <pre><code> //get my json file as Map
   Map&lt;String, JsonNode&gt; cm = null;
      try {
          cm = mapper.readValue(new File(path), Map.class);
      } catch (JsonParseException e) {...} 
    //add some key, value pairs to my map
  
   JsonNodeFactory factory = JsonNodeFactory.instance;
      ObjectNode node = factory.objectNode(); 
     //add to a jsonNode
    node.putAll(cm);
  </code></pre>
  
  <p>So I get an exception cause one of the key-value pairs looks like this: {"id":7}
  and it seems like there is no way of converting the Integer(7) back to json even if it was one before. </p>
  
  <p>Any Ideas? </p>
  
  <p>The exeption:</p>
  
  <pre><code>   Exception in thread "main" java.lang.ClassCastException: java.lang.Integer cannot be    cast to com.fasterxml.jackson.databind.JsonNode
  </code></pre>