/*
 * @(#)ConnectionEventListener.java	1.8 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package javax.sql;

/** 
 * <P>
 * An object that registers to be notified of events generated by a 
 * <code>PooledConnection</code> object.
 * <P>
 * The <code>ConnectionEventListener</code> interface is implemented by a
 * connection pooling component.  A connection pooling component will
 * usually be provided by a JDBC driver vendor or another system software
 * vendor.  A JDBC driver notifies a <code>ConnectionEventListener</code>
 * object when an application is finished using a pooled connection with
 * which the listener has registered.  The notification 
 * occurs after the application calls the method <code>close</code> on
 * its representation of a <code>PooledConnection</code> object.  A 
 * <code>ConnectionEventListener</code> is also notified when a
 * connection error occurs due to the fact that the <code>PooledConnection</code>
 * is unfit for future use---the server has crashed, for example. 
 * The listener is notified by the JDBC driver just before the driver throws an
 * <code>SQLException</code> to the application using the 
 * <code>PooledConnection</code> object.
 *
 * @since 1.4
 */

public interface ConnectionEventListener extends java.util.EventListener {

  /**
   * Notifies this <code>ConnectionEventListener</code> that
   * the application has called the method <code>close</code> on its
   * representation of a pooled connection.
   *
   * @param event an event object describing the source of 
   * the event
   */
  void connectionClosed(ConnectionEvent event);
      
  /**
   * Notifies this <code>ConnectionEventListener</code> that
   * a fatal error has occurred and the pooled connection can
   * no longer be used.  The driver makes this notification just
   * before it throws the application the <code>SQLException</code>
   * contained in the given <code>ConnectionEvent</code> object.
   *
   * @param event an event object describing the source of 
   * the event and containing the <code>SQLException</code> that the
   * driver is about to throw
   */
  void connectionErrorOccurred(ConnectionEvent event);

 }