org.apache.river.lease

Class AbstractLease

java.lang.Object

org.apache.river.lease.AbstractLease

All Implemented Interfaces:

Serializable, Lease

Direct Known Subclasses:

FiddlerLease, LandlordLease, RegistrarLease

public abstract class AbstractLease
extends Object
implements Lease, Serializable

A base class for implementing lease objects. This class takes care of absolute vs relative time issues and implements some of the Lease methods. The subclass is responsible for implementing: doRenew, cancel, createLeaseMap, canBatch, hashCode, equals, and serialization of any subclass state.

Author:

Sun Microsystems, Inc.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected long	expiration The lease expiration, in local absolute time.
protected int	serialFormat Serialization format for the expiration.
private static long	serialVersionUID

Fields inherited from interface net.jini.core.lease.Lease

ABSOLUTE, ANY, DURATION, FOREVER

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractLease(long expiration) Construct a relative-format lease.

Method Summary

Modifier and Type	Method and Description
protected abstract long	doRenew(long duration) Renew the lease for a duration relative to now, and return the duration actually granted.
long	getExpiration() Return the lease expiration.
int	getSerialFormat() Return the serialization format for the expiration.
private void	readObject(ObjectInputStream stream) If serialFormat is DURATION, add the current time to the expiration, to make it absolute (and if the result of the addition is negative, correct the overflow by resetting the expiration to Long.MAX_VALUE).
private void	readObjectNoData() Throws an InvalidObjectException.
void	renew(long duration) Renew the lease for a duration relative to now.
void	setSerialFormat(int format) Set the serialization format for the expiration.
private void	writeObject(ObjectOutputStream stream)

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.jini.core.lease.Lease

canBatch, cancel, createLeaseMap

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

expiration

protected transient volatile long expiration

The lease expiration, in local absolute time. This field has been made volatile to ensure visibility, since synchronized access isn't guaranteed to be performed by overriding classes.

serialFormat

protected volatile int serialFormat

Serialization format for the expiration.

Constructor Detail

AbstractLease

protected AbstractLease(long expiration)

Construct a relative-format lease.

Method Detail

getExpiration

public long getExpiration()

Return the lease expiration.

Specified by:

getExpiration in interface Lease

Returns:

a long that indicates the time that the lease will expire

getSerialFormat

public int getSerialFormat()

Return the serialization format for the expiration.

Specified by:

getSerialFormat in interface Lease

Returns:

an int representing the serial format value

See Also:

Lease.setSerialFormat(int)

setSerialFormat

public void setSerialFormat(int format)

Set the serialization format for the expiration.

Specified by:

setSerialFormat in interface Lease

Parameters:

format - DURATION or ABSOLUTE

See Also:

Lease.getSerialFormat()

renew

public void renew(long duration)
           throws UnknownLeaseException,
                  LeaseDeniedException,
                  RemoteException

Renew the lease for a duration relative to now.

Specified by:

renew in interface Lease

Parameters:

duration - the requested duration in milliseconds

Throws:

UnknownLeaseException - the lease being renewed is unknown to the lease grantor

LeaseDeniedException - the lease grantor is unable or unwilling to renew the lease

RemoteException

doRenew

protected abstract long doRenew(long duration)
                         throws UnknownLeaseException,
                                LeaseDeniedException,
                                RemoteException

Renew the lease for a duration relative to now, and return the duration actually granted.

Throws:

UnknownLeaseException

LeaseDeniedException

RemoteException

writeObject

private void writeObject(ObjectOutputStream stream)
                  throws IOException

Throws:

IOException

readObjectNoData

private void readObjectNoData()
                       throws InvalidObjectException

Throws an InvalidObjectException.

Throws:

InvalidObjectException - unconditionally

readObject

private void readObject(ObjectInputStream stream)
                 throws IOException,
                        ClassNotFoundException

If serialFormat is DURATION, add the current time to the expiration, to make it absolute (and if the result of the addition is negative, correct the overflow by resetting the expiration to Long.MAX_VALUE).

Throws:

InvalidObjectException - if serialFormat is neither ABSOLUTE nor DURATION

IOException

ClassNotFoundException