title: SpringData MongoDB cannot determine IsNewStrategy during Auditing
body: <p>I am trying to enable Auditing using Annotations. My domain class has @Id field that is populated while constructing the object. I have added a java.util.Date field for lastModified and annotated it with @LastModifiedDate.</p>
  
  <pre class="lang-java prettyprint-override"><code>@Document
  public class Book {
      @Id
      private String name;
      private String isbn;
      @LastModifiedDate
      private Date lastModified;
  
      public Book(String name) {
          this.name = name;
      }
  }
  </code></pre>
  
  <p>I have enabled auditing in the Spring Configuration XML using <code>&lt;mongo:auditing/&gt;.</code></p>
  
  <p>When I try to save an instance of my object, I get the following error:</p>
  
  <pre class="lang-java prettyprint-override"><code>Book book1 = new Book("ABCD");
  mongoOps.save(book1);
  </code></pre>
  
  <p>java.lang.IllegalArgumentException: Unsupported entity com.pankaj.Book! Could not determine IsNewStrategy.</p>
  
  <p>I do not want to use the Auditable interface nor extend my domain classes from AbstractAuditable. I only want to use the Annotations.
  Since I am not interested in the @CreatedBy and the @LastModifiedBy, I am not implementing the AuditAware interface as well. </p>
  
  <p>I just want the @LastModifiedDate to work for my domain classes. What am I missing?</p>
  
  <p>I am using version 1.7.0 of SpringData MongoDB. </p>