code: private static Object parseAsObject(String json) {
  		if ( StringHelper.isNullOrEmptyString( json ) ) {
  			return null;
  		}
  		Document object = Document.parse( "{ 'json': " + json + "}" );
  		return object.get( "json" );
  	}
docs: parse JSON
  @param json
  @return
  @see <a href="http://stackoverflow.com/questions/34436952/json-parse-equivalent-in-mongo-driver-3-x-for-java"> JSON.parse equivalent</a>