context.arch.discoverer.lease
Class LeasesKeeper

java.lang.Object
  context.arch.discoverer.lease.LeasesKeeper

public class LeasesKeeper

extends java.lang.Object

A component registers to the discoverer for a given period of time that is defined with a lease. That allows the discovery system to make sure a component is still available. This class keeps all information about the context components leases that are registered. It contains a LeasesWatcher object that watches the end of leases each xx minutes as defined in the Lease class by the constant Lease.TIME_SLOT_MILLIS. If the LeaseKeeper detects the end of a lease, it sends it to the discoverer that will send a checking message to the component.

Author:

Agathe

See Also:

LeasesWatcher, Discoverer

Field Summary

protected java.util.Hashtable	leases All leases, associates the component (Integer)index -> Lease object
protected DiscovererMediator	mediator The discoverer object
protected LeasesWatcher	watcher The watcher that triggers the leases examination

Constructor Summary

LeasesKeeper(DiscovererMediator mediator)
Creates new LeasesKeeper TO COMPLETE (if the discoverer restarts from a log file)

Method Summary

void	addLease(Lease lease) Adds a Lease object and update the LeaseWatcher object
java.lang.Integer	contains(java.lang.Integer componentIndex) This method tests if an index of a ComponentDescription exists
boolean	existingComponentDescription(java.lang.Integer componentDescriptionIndex) Tests if an index corresponds to an existing ComponentDescription in the discoverer
void	leaseEndNotificationTo(java.util.ArrayList listOfLeaseEnd) This method allows to send a list of leases that should end to the discoverer.
Lease	removeLease(java.lang.Integer indexToRemove) This method allows to remove a Lease corresponding to the index
boolean	renewLease(Lease renewal) This method allows to renew an exiting lease
java.lang.String	toString() Returns a printable version of this object

Methods inherited from class java.lang.Object

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

Field Detail

mediator

protected DiscovererMediator mediator

The discoverer object

leases

protected java.util.Hashtable leases

All leases, associates the component (Integer)index -> Lease object

watcher

protected LeasesWatcher watcher

The watcher that triggers the leases examination

Constructor Detail

LeasesKeeper

public LeasesKeeper(DiscovererMediator mediator)

Creates new LeasesKeeper TO COMPLETE (if the discoverer restarts from a log file)

Method Detail

addLease

public void addLease(Lease lease)

Adds a Lease object and update the LeaseWatcher object

Parameters:

lease - The Lease object

leaseEndNotificationTo

public void leaseEndNotificationTo(java.util.ArrayList listOfLeaseEnd)

This method allows to send a list of leases that should end to the discoverer.

Parameters:

listOfLeaseEnd - The leases to send to the discoverer

removeLease

public Lease removeLease(java.lang.Integer indexToRemove)

This method allows to remove a Lease corresponding to the index

Parameters:

indexToRemove - The index of the ComponentDescription for which we want to remove the lease

Returns:

Lease The removed Lease object

contains

public java.lang.Integer contains(java.lang.Integer componentIndex)

This method tests if an index of a ComponentDescription exists

Parameters:

componentIndex - The Integer to test

Returns:

boolean True if this object contains componentIndex

toString

public java.lang.String toString()

Returns a printable version of this object

Returns:

String

renewLease

public boolean renewLease(Lease renewal)

This method allows to renew an exiting lease

Parameters:

renewal - The new lease

Returns:

boolean True if the lease has been updated for the given index

existingComponentDescription

public boolean existingComponentDescription(java.lang.Integer componentDescriptionIndex)

Tests if an index corresponds to an existing ComponentDescription in the discoverer

Parameters:

componentDescriptionIndex - The index of the object to test

Returns:

boolean True if there is an existing component description with this index in the discoverer