code: public void setFilterNot( final String attributeName, final String value )
      {
          this.setFilter( attributeName, value );
          filter = "(!" + filter + ")";
      }
docs: Set up a not exists filter for an attribute name and value pair.
  
  <table border="1"><caption>Example Values</caption>
  <tr><td><b>Attribute</b></td><td><b>Value</b></td></tr>
  <tr><td>givenName</td><td>John</td></tr>
  </table>
  <p><i>Result</i></p>
  <code>(!(givenName=John))</code>
  
  @param attributeName A valid attribute name
  @param value         A value that, if it exists, will cause the object to be excluded from the result set.