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package javax.sql;


 An object that registers to be notified of events generated by a PooledConnection object. 
 The ConnectionEventListener 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 ConnectionEventListener 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 close on its representation of a PooledConnection object. A ConnectionEventListener is also notified when a connection error occurs due to the fact that the PooledConnection 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 SQLException to the application using the PooledConnection object. 
Since:1.4
/**
 * <P>
 * An object that registers to be notified of events generated by a
 * {@code PooledConnection} object.
 * <P>
 * The {@code ConnectionEventListener} 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}
 * 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} on
 * its representation of a {@code PooledConnection} object.  A
 * {@code ConnectionEventListener} is also notified when a
 * connection error occurs due to the fact that the {@code PooledConnection}
 * 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} to the application using the
 * {@code PooledConnection} object.
 *
 * @since 1.4
 */

public interface ConnectionEventListener extends java.util.EventListener {

  
Notifies this ConnectionEventListener that the application has called the method close on its representation of a pooled connection. 
Params:
  • event – an event object describing the source of
the event
/**
   * Notifies this {@code ConnectionEventListener} that
   * the application has called the method {@code close} on its
   * representation of a pooled connection.
   *
   * @param event an event object describing the source of
   * the event
   */
  void connectionClosed(ConnectionEvent event);

  
Notifies this ConnectionEventListener 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 SQLException contained in the given ConnectionEvent object. 
Params:
  • event – an event object describing the source of the event and containing the SQLException that the driver is about to throw
/**
   * Notifies this {@code ConnectionEventListener} 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}
   * contained in the given {@code ConnectionEvent} object.
   *
   * @param event an event object describing the source of
   * the event and containing the {@code SQLException} that the
   * driver is about to throw
   */
  void connectionErrorOccurred(ConnectionEvent event);

 }