CountingMigrationAwareService (Hazelcast Root 3.12.9 API)

java.lang.Object
- com.hazelcast.spi.impl.CountingMigrationAwareService

All Implemented Interfaces:

FragmentedMigrationAwareService, MigrationAwareService
```
public class CountingMigrationAwareService
extends Object
implements FragmentedMigrationAwareService
```
A MigrationAwareService that delegates to another MigrationAwareService and keeps track of the number of migrations concerning the partition owner (either as current or new replica index) currently in-flight.

Constructor Summary

Constructors
Constructor and Description

CountingMigrationAwareService(FragmentedMigrationAwareService migrationAwareService)

Constructors
Constructor and Description
`CountingMigrationAwareService(FragmentedMigrationAwareService migrationAwareService)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`beforeMigration(PartitionMigrationEvent event)` Called before migration process starts, on both source and destination members.
`void`	`commitMigration(PartitionMigrationEvent event)` Commits the migration process for this service, on both source and destination members.
`Collection<ServiceNamespace>`	`getAllServiceNamespaces(PartitionReplicationEvent event)` Returns all known namespaces for given replication event.
`int`	`getMigrationStamp()` Returns a stamp to denote current migration state which can later be validated using `validateMigrationStamp(int)`.
`boolean`	`isKnownServiceNamespace(ServiceNamespace namespace)` Returns true if namespace is known by this service, false otherwise
`Operation`	`prepareReplicationOperation(PartitionReplicationEvent event)` Returns an operation to replicate service data and/or state for a specific partition replica on another cluster member.
`Operation`	`prepareReplicationOperation(PartitionReplicationEvent event, Collection<ServiceNamespace> namespaces)` Returns an operation to replicate service data and/or state for a specific partition replica and namespaces on another cluster member.
`void`	`rollbackMigration(PartitionMigrationEvent event)` Rollback the migration process for this service, on both source and destination members.
`boolean`	`validateMigrationStamp(int stamp)` Returns true if there's no primary replica migrations started and/or completed since issuance of the given stamp.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - CountingMigrationAwareService
```
public CountingMigrationAwareService(FragmentedMigrationAwareService migrationAwareService)
```
- Method Detail
  - getAllServiceNamespaces
```
public Collection<ServiceNamespace> getAllServiceNamespaces(PartitionReplicationEvent event)
```
    Description copied from interface: FragmentedMigrationAwareService
    
    Returns all known namespaces for given replication event.
    
    Specified by:
    
    getAllServiceNamespaces in interface FragmentedMigrationAwareService
    
    Parameters:
    
    event - replication event
    
    Returns:
    
    all known service namespaces for the replication
  - isKnownServiceNamespace
```
public boolean isKnownServiceNamespace(ServiceNamespace namespace)
```
    Description copied from interface: FragmentedMigrationAwareService
    
    Returns true if namespace is known by this service, false otherwise
    
    Specified by:
    
    isKnownServiceNamespace in interface FragmentedMigrationAwareService
    
    Parameters:
    
    namespace - namespace
    
    Returns:
    
    true if namespace is known by this service, false otherwise
  - prepareReplicationOperation
```
public Operation prepareReplicationOperation(PartitionReplicationEvent event)
```
    Description copied from interface: MigrationAwareService
    
    Returns an operation to replicate service data and/or state for a specific partition replica on another cluster member.
    This method will be called on source member whenever partitioning system requires to copy/replicate a partition replica. Returned operation will be executed on destination member. If operation fails by throwing exception, migration process will fail and will be rolled back.
    Returning null is allowed and means service does not have anything to replicate.
    
    Specified by:
    
    prepareReplicationOperation in interface MigrationAwareService
    
    Parameters:
    
    event - replication
    
    Returns:
    
    replication operation or null if nothing will be replicated
  - prepareReplicationOperation
```
public Operation prepareReplicationOperation(PartitionReplicationEvent event,
                                             Collection<ServiceNamespace> namespaces)
```
    Description copied from interface: FragmentedMigrationAwareService
    
    Returns an operation to replicate service data and/or state for a specific partition replica and namespaces on another cluster member. This method is very similar to MigrationAwareService.prepareReplicationOperation(PartitionReplicationEvent), instead of copying whole partition replica, allows copying only some portion of replica, specified by given namespaces.
    This method will be called on source member whenever partitioning system requires to copy/replicate a partition replica. Returned operation will be executed on destination member. If operation fails by throwing exception, migration process will fail and will be rolled back.
    Returning null is allowed and means service does not have anything to replicate.
    
    Specified by:
    
    prepareReplicationOperation in interface FragmentedMigrationAwareService
    
    Parameters:
    
    event - replication event
    
    namespaces - replica fragment namespaces to replicate
    
    Returns:
    
    replication operation or null if nothing will be replicated
    
    See Also:
    
    MigrationAwareService.prepareReplicationOperation(PartitionReplicationEvent)
  - beforeMigration
```
public void beforeMigration(PartitionMigrationEvent event)
```
    Description copied from interface: MigrationAwareService
    
    Called before migration process starts, on both source and destination members.
    Service can take actions required before migration. Migration process will block until this method returns. If this method fails by throwing an exception, migration process for specific partition will fail and will be rolled back.
    
    Specified by:
    
    beforeMigration in interface MigrationAwareService
    
    Parameters:
    
    event - migration event
  - commitMigration
```
public void commitMigration(PartitionMigrationEvent event)
```
    Description copied from interface: MigrationAwareService
    
    Commits the migration process for this service, on both source and destination members. This method will be called after all replication operations are executed successfully on destination and master member receives success response from all participants.
    Commit is not expected to fail at this point, all exceptions will be suppressed and logged. Implementations of this method must be thread safe as this method may be called concurrently for different migrations on different partitions.
    
    Specified by:
    
    commitMigration in interface MigrationAwareService
    
    Parameters:
    
    event - migration event
  - rollbackMigration
```
public void rollbackMigration(PartitionMigrationEvent event)
```
    Description copied from interface: MigrationAwareService
    
    Rollback the migration process for this service, on both source and destination members. This method will be called when migration process fails at any moment. Reasons for failure may be an exception thrown on any migration step or failure(s) of any of the migration participants; either master or source or destination.
    Rollback is not expected to fail at this point, all exceptions will be suppressed and logged. Implementations of this method must be thread safe as this method may be called concurrently for different migrations on different partitions.
    
    Specified by:
    
    rollbackMigration in interface MigrationAwareService
    
    Parameters:
    
    event - migration event
  - getMigrationStamp
```
public int getMigrationStamp()
```
    Returns a stamp to denote current migration state which can later be validated using validateMigrationStamp(int).
    
    Returns:
    
    migration stamp
  - validateMigrationStamp
```
public boolean validateMigrationStamp(int stamp)
```
    Returns true if there's no primary replica migrations started and/or completed since issuance of the given stamp. Otherwise returns false, if there's an ongoing migration when stamp is issued or a new migration is started (and optionally completed) after stamp is issued.
    
    Parameters:
    
    stamp - a stamp
    
    Returns:
    
    true stamp is valid since issuance of the given stamp, false otherwise

Class CountingMigrationAwareService

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

CountingMigrationAwareService

Method Detail

getAllServiceNamespaces

isKnownServiceNamespace

prepareReplicationOperation

prepareReplicationOperation

beforeMigration

commitMigration

rollbackMigration

getMigrationStamp

validateMigrationStamp