public void addAttachment(URI url){
  if (url == null)   return;
  if (m_attachments == null)   m_attachments=new ArrayList<Object>();
  m_attachments.add(url);
}

public void addAttachment ( URI url ) { if ( url == null ) return ; if ( m_attachments == null ) m_attachments = new ArrayList < Object > ( ) ; m_attachments . add ( url ) ; }
add url based file attachment
