title: Jaxb marshalling with custom annotations
body: <p>I have a requirement, to marshall/unmarshall some elements of java pojo depending upon a custom annotation marked on the field.
  suppose there are 3 fields in my java pojp</p>
  
  <pre><code>@CustomVersion("v1")
  private String field1;
  @CustomVersion("v1","v2")
  private String field2;
  @CustomVersion("v2")
  private String field3;
  </code></pre>
  
  <p>i would like to marshall only the fields with v1 if i pass version="v1" parameter while conversion in jaxb. if i pass v2, all fields with v2 annotation should only be marshalled.</p>
  
  <p>is that even possible using jaxb? i am sure selective marshalling would be supported through some library or way, am not still able to figure it out after quite some searching.
  any help or advice or pointers are highly appreciated.</p>