public void delete(String name) throws IOException {
  if (name.equalsIgnoreCase(NUMBER)) {
    serial=null;
  }
 else {
    throw new IOException("Attribute name not recognized by " + "CertAttrSet:CertificateSerialNumber.");
  }
}

public void delete ( String name ) throws IOException { if ( name . equalsIgnoreCase ( NUMBER ) ) { serial = null ; } else { throw new IOException ( "Attribute name not recognized by " + "CertAttrSet:CertificateSerialNumber." ) ; } }
delete the attribute value .
