jgroup.arm.recovery
Class KeepMinimalInPartition

java.lang.Object
  jgroup.arm.recovery.AbstractRecoveryStrategy
      jgroup.arm.recovery.KeepMinimalInPartition

All Implemented Interfaces:

RecoveryStrategy

Direct Known Subclasses:

KeepInitialInPartition

public class KeepMinimalInPartition
extends AbstractRecoveryStrategy

If the current number of replicas falls below the minimal redundancy specified for this replica, and the number of available hosts in this partition is greater than the minimal redundancy then create new replicas to compensate for the lost redundancy.

Since:

Jgroup 1.2

Author:

Hein Meling

Field Summary

Fields inherited from class jgroup.arm.recovery.AbstractRecoveryStrategy

app, distScheme, missing

Constructor Summary

KeepMinimalInPartition()

Method Summary

boolean	handleFailure(HostSet hosts) FIXME UPDATE DOCUMENTATION: The KeepMinimalInPartition implementation simply assume that the servers do not maintain any state or has some other means of recovering their state, and tries to relocate the replicas to a new set of hosts.
boolean	relocateReplica(Host host) Relocate the application replica that were running on the given host.
boolean	restartReplica(Host host) Restart the given replica on the given host.

Methods inherited from class jgroup.arm.recovery.AbstractRecoveryStrategy

deltaRedundancy, initialize, needsRecovery, prepareRecovery

Methods inherited from class java.lang.Object

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

Constructor Detail

KeepMinimalInPartition

public KeepMinimalInPartition()

Method Detail

handleFailure

public boolean handleFailure(HostSet hosts)

FIXME UPDATE DOCUMENTATION: The KeepMinimalInPartition implementation simply assume that the servers do not maintain any state or has some other means of recovering their state, and tries to relocate the replicas to a new set of hosts.

Parameters:

hosts - The set of hosts on which the application was running, but has now failed.

Returns:

True if all replicas replacement repliacs has been created successfully, false otherwise.

restartReplica

public boolean restartReplica(Host host)

Description copied from interface: RecoveryStrategy

Restart the given replica on the given host. This method differes from the one below in that it will try to instatiate the replica on the same host on which the failed replica was running. That is it will be invoked only when the execution service is still believed to be available on that host.

Parameters:

host - The host on which the replica was running.

Returns:

True if recovery was successful; false otherwise.

relocateReplica

public boolean relocateReplica(Host host)

Description copied from interface: RecoveryStrategy

Relocate the application replica that were running on the given host. The new location should be obtain through the DistributionScheme provided by the replication manager.

Parameters:

host - The host on which the replica were running.

Returns:

True if recovery was successful; false otherwise.