com.hazelcast.spi.hotrestart

Class PersistentConfigDescriptors

java.lang.Object

com.hazelcast.spi.hotrestart.PersistentConfigDescriptors

public class PersistentConfigDescriptors
extends Object

Maintains the in-memory mapping of names and 32-bit cache IDs to ConfigDescriptors. The names are generated from the service name and distributed object name and the cache ID is generated by a sequence. Also persists this information on disk with an additional config per cache descriptor.

Constructor Summary

Constructors

Constructor and Description
PersistentConfigDescriptors(File instanceHome)

Method Summary

Modifier and Type	Method and Description
void	backup(File targetDir) Copies the contents of the persisted cache descriptors to a folder with the name CONFIG_FOLDER under the targetDir.
void	ensureHas(com.hazelcast.internal.serialization.InternalSerializationService serializationService, String serviceName, String name, Object config) Ensures that this instance contains mapping for a ConfigDescriptor.
ConfigDescriptor	getDescriptor(long prefix) Returns the ConfigDescriptor for the given prefix.
long	getPrefix(String serviceName, String name, int partitionId) Returns the prefix for the given parameters.
void	reset()
static int	toPartitionId(long prefix) Returns the partition ID for the prefix.

Methods inherited from class java.lang.Object

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

Constructor Detail

PersistentConfigDescriptors

public PersistentConfigDescriptors(File instanceHome)

Method Detail

reset

public void reset()

getPrefix

public long getPrefix(String serviceName,
                      String name,
                      int partitionId)

Returns the prefix for the given parameters. The prefix is generated from the cache ID and the given partitionId. The cache ID is retrieved from the persisted cache descriptors map by serviceName and name.

Parameters:

serviceName - the service name

name - the distributed object name

partitionId - the partition ID

Returns:

the prefix

getDescriptor

public ConfigDescriptor getDescriptor(long prefix)

Returns the ConfigDescriptor for the given prefix. The higher 4 bytes in the prefix should represent the cache ID.

Parameters:

prefix - the prefix for which the ConfigDescriptor is returned

Returns:

the cache descriptor

ensureHas

public void ensureHas(com.hazelcast.internal.serialization.InternalSerializationService serializationService,
                      String serviceName,
                      String name,
                      Object config)

Ensures that this instance contains mapping for a ConfigDescriptor. If there is no existing mapping, creates one by assigning it a new ID. It then persists the newly created descriptor on disk.

Parameters:

serializationService - the serialization service used for serializing a newly created descriptor to disk

serviceName - the name of the service (e.g. ICacheService.SERVICE_NAME or MapService.SERVICE_NAME)

name - the name of the distributed object

config - configuration written to disk alongside the newly created descriptor

toPartitionId

public static int toPartitionId(long prefix)

Returns the partition ID for the prefix. Currently the lower 4 bytes of the prefix represent the partition ID.

Parameters:

prefix - the prefix

Returns:

the partition ID

backup

public void backup(File targetDir)

Copies the contents of the persisted cache descriptors to a folder with the name CONFIG_FOLDER under the targetDir. This method does not synchronize with the rest of the code so for consistent descriptors it is necessary to ensure that no cache descriptor changes or additions are in progress.

Parameters:

targetDir - the directory under which the folder with the descriptors will be copied