org.apache.river.landlord

Interface Landlord

All Superinterfaces:

Remote

public interface Landlord
extends Remote

Interface that granters of leases must implement in order to work with the LandlordLease implementation of the Lease interface.

Since:

2.0

Author:

Sun Microsystems, Inc.

See Also:

Lease, LandlordLease

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	Landlord.RenewResults Simple class that holds return values of the Landlord.renewAll method.

Method Summary

Modifier and Type	Method and Description
void	cancel(Uuid cookie) Called by the lease when its cancel method is called.
Map	cancelAll(Uuid[] cookies) Called by the lease map when its cancelAll method is called.
long	renew(Uuid cookie, long duration) Called by the lease when its renew method is called.
Landlord.RenewResults	renewAll(Uuid[] cookies, long[] durations) Called by the lease map when its renewAll method is called.

Method Detail

renew

long renew(Uuid cookie,
           long duration)
    throws LeaseDeniedException,
           UnknownLeaseException,
           RemoteException

Called by the lease when its renew method is called. Renews the lease that is associated with the given cookie.

Parameters:

cookie - the Uuid associated with the lease who's renew method was called

duration - argument passed to the renew call

Returns:

The new duration the lease should have

Throws:

LeaseDeniedException - if the landlord is unwilling to renew the lease

UnknownLeaseException - if landlord does not know about a lease with the specified cookie

RemoteException - if a communications failure occurs

cancel

void cancel(Uuid cookie)
     throws UnknownLeaseException,
            RemoteException

Called by the lease when its cancel method is called. Cancels the lease that is associated with the given cookie.

Parameters:

cookie - the Uuid associated with the lease who's renew method was called

Throws:

UnknownLeaseException - if landlord does not know about a lease with the specified cookie

RemoteException - if a communications failure occurs

renewAll

Landlord.RenewResults renewAll(Uuid[] cookies,
                               long[] durations)
                        throws RemoteException

Called by the lease map when its renewAll method is called. Should renew the lease that is associated with each element of cookies

Parameters:

cookies - an array of Uuids, each universally and uniquely identifying a lease granted by this Landlord

durations - an array of longs, each representing an a duration in milliseconds that the client wants the lease associated with the Uuid from the corresponding element of cookies renewed for

Returns:

A RenewResults object that contains the new duration of each lease that was successfully renewed or the exception encountered for each lease that could not be renewed

Throws:

RemoteException - if a communications failure occurs

cancelAll

Map cancelAll(Uuid[] cookies)
       throws RemoteException

Called by the lease map when its cancelAll method is called. Should cancel the lease that is associated with each element of cookies This method is now default, because it is unsafe to return a Map that has been serialized, without having its invariants checked during deserialization. A gadget attack could utilize the map to contain other objects.

Parameters:

cookies - an array of Uuids, each universally and uniquely identifying a lease granted by this Landlord

Returns:

If all the leases specified in the cookies could be canceled return null. Otherwise, return a Map that for each failed cancel attempt maps the corresponding cookie object to an exception describing the failure.

Throws:

RemoteException - if a communications failure occurs