net.jini.lease

Class LeaseRenewalEvent

java.lang.Object

java.util.EventObject

net.jini.lease.LeaseRenewalEvent

All Implemented Interfaces:

Serializable

public class LeaseRenewalEvent
extends EventObject

Event generated when a LeaseRenewalManager cannot renew a lease.

The LeaseRenewalEvent instances are sent to the LeaseListener (if any) associated with a given lease when the lease was added to the managed set. These events are typically generated because one of the following conditions occur:

• After successfully renewing a lease any number of times and experiencing no failures, the LeaseRenewalManager determines, prior to the next renewal attempt, that the actual expiration time of the lease has passed, implying that any further attempt to renew the lease would be fruitless.
• An indefinite exception occurs during each attempt to renew a lease, from the point that the first such exception occurs until the point when the LeaseRenewalManager determines that lease's actual expiration time has passed.
• A definite exception occurs during a lease renewal attempt.

Note that bad object exceptions, bad invocation exceptions, and LeaseExceptions are all considered definite exceptions.

This class encapsulates information about both the lease for which the failure occurred, as well as information about the condition that caused the renewal attempt to fail.

This class is a subclass of the class EventObject, adding the following additional items of abstract state:

• The lease on which the renewal attempt failed, and to which the event pertains
• The desired expiration time of the affected lease
• The Throwable associated with the last renewal attempt (if any)

In addition to the methods of the EventObject class, this class defines methods through which this additional state may be retrieved.

The source associated with a LeaseRenewalEvent will be the LeaseRenewalManager that generated the event.

Author:

Sun Microsystems, Inc.

See Also:

Lease, LeaseException, LeaseRenewalManager, LeaseListener, EventObject, Serialized Form

Field Summary

Fields inherited from class java.util.EventObject

source

Constructor Summary

Constructors

Constructor and Description
LeaseRenewalEvent(Object source, Lease lease, long expiration, Throwable ex) Constructs an instance of this class with the specified state.

Method Summary

Modifier and Type	Method and Description
Throwable	getException() Returns the exception (if any) that caused the event to be sent.
long	getExpiration() Returns the desired expiration time of the lease to which event pertains.
Lease	getLease() Returns a reference to the lease to which the event pertains.

Methods inherited from class java.util.EventObject

getSource, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

LeaseRenewalEvent

public LeaseRenewalEvent(Object source,
                         Lease lease,
                         long expiration,
                         Throwable ex)

Constructs an instance of this class with the specified state.

Parameters:

source - reference to the instance of the LeaseRenewalManager that generated the event

lease - the lease to which the event pertains

expiration - the desired expiration time for the affected lease

ex - the Throwable associated with the last renewal attempt (if any)

See Also:

Lease, LeaseRenewalManager

Method Detail

getLease

public Lease getLease()

Returns a reference to the lease to which the event pertains.

Returns:

the Lease object corresponding to the lease on which the renewal attempt failed

See Also:

Lease

getExpiration

public long getExpiration()

Returns the desired expiration time of the lease to which event pertains.

Returns:

a long value that represents the desired expiration time of the lease on which the renewal attempt failed

getException

public Throwable getException()

Returns the exception (if any) that caused the event to be sent. The conditions under which the event may be sent, and the related values returned by this method, are as follows:

• When any lease in the managed set has passed its actual expiration time, and either the most recent renewal attempt was successful or there have been no renewal attempts, the LeaseRenewalManager will cease any further attempts to renew the lease, and will send a LeaseRenewalEvent with no associated exception. In this case, invoking this method will return null.
• For any lease from the managed set for which the most recent renewal attempt was unsuccessful because of the occurrence of a indefinite exception, the LeaseRenewalManager will continue to attempt to renew the affected lease at the appropriate times until: the renewal succeeds, the lease's expiration time has passed, or a renewal attempt throws a definite exception. If a definite exception is thrown or the lease expires, the LeaseRenewalManager will cease any further attempts to renew the lease, and will send a LeaseRenewalEvent containing the exception associated with the last renewal attempt.
• If, while attempting to renew a lease from the managed set, a definite exception is encountered, the LeaseRenewalManager will cease any further attempts to renew the lease, and will send a LeaseRenewalEvent containing the particular exception that occurred.

Returns:

an instance of Throwable or null, indicating the condition that caused the LeaseRenewalManager to fail to renew the affected lease