Package com.hazelcast.core

Interface HazelcastInstance

All Known Subinterfaces:
HazelcastOSGiInstance
public interface HazelcastInstance
Hazelcast instance. Each instance is a member and/or client in a Hazelcast cluster. When you want to use Hazelcast's distributed data structures, you must first create an instance. Multiple Hazelcast instances can be created on a single JVM.

Instances should be shut down explicitly. See the shutdown() method. If the instance is a client and you don't shut it down explicitly, it will continue to run and even connect to another live member if the one it was connected to fails.

Each Hazelcast instance has its own socket and threads.

See Also:

  • Method Details

    • getName

      @Nonnull String getName()
      Returns the name of this Hazelcast instance.
      Returns:
      name of this Hazelcast instance

    • getQueue

      @Nonnull <E> IQueue<E> getQueue(@Nonnull String name)
      Creates or returns the distributed queue instance with the specified name.
      Type Parameters:
      E - queue item type
      Parameters:
      name - name of the distributed queue
      Returns:
      distributed queue instance with the specified name

    • getTopic

      @Nonnull <E> ITopic<E> getTopic(@Nonnull String name)
      Creates or returns the distributed topic instance with the specified name.
      Type Parameters:
      E - the type of the topic message
      Parameters:
      name - name of the distributed topic
      Returns:
      distributed topic instance with the specified name

    • getSet

      @Nonnull <E> ISet<E> getSet(@Nonnull String name)
      Creates or returns the distributed set instance with the specified name.
      Type Parameters:
      E - the type of elements maintained by the set
      Parameters:
      name - name of the distributed set
      Returns:
      distributed set instance with the specified name

    • getList

      @Nonnull <E> IList<E> getList(@Nonnull String name)
      Creates or returns the distributed list instance with the specified name. Index based operations on the list are not supported.
      Type Parameters:
      E - the type of elements maintained by the list
      Parameters:
      name - name of the distributed list
      Returns:
      distributed list instance with the specified name

    • getMap

      @Nonnull <K, V> IMap<K,V> getMap(@Nonnull String name)
      Creates or returns the distributed map instance with the specified name.
      Type Parameters:
      K - key type
      V - value type
      Parameters:
      name - name of the distributed map
      Returns:
      distributed map instance with the specified name

    • getReplicatedMap

      @Nonnull <K, V> ReplicatedMap<K,V> getReplicatedMap(@Nonnull String name)
      Creates or returns the replicated map instance with the specified name.
      Type Parameters:
      K - the type of keys maintained by the replicated map
      V - the type of mapped values
      Parameters:
      name - name of the distributed map
      Returns:
      replicated map instance with specified name
      Throws:
      ReplicatedMapCantBeCreatedOnLiteMemberException - if it is called on a lite member
      Since:
      3.2

    • getMultiMap

      @Nonnull <K, V> MultiMap<K,V> getMultiMap(@Nonnull String name)
      Creates or returns the distributed multimap instance with the specified name.
      Type Parameters:
      K - type of the multimap key
      V - type of the multimap value
      Parameters:
      name - name of the distributed multimap
      Returns:
      distributed multimap instance with the specified name

    • getRingbuffer

      @Nonnull <E> Ringbuffer<E> getRingbuffer(@Nonnull String name)
      Creates or returns the distributed Ringbuffer instance with the specified name.
      Type Parameters:
      E - the type of the elements that the Ringbuffer contains
      Parameters:
      name - name of the distributed Ringbuffer
      Returns:
      distributed RingBuffer instance with the specified name

    • getReliableTopic

      @Nonnull <E> ITopic<E> getReliableTopic(@Nonnull String name)
      Creates or returns the reliable topic instance with the specified name.
      Type Parameters:
      E - the type of the topic message
      Parameters:
      name - name of the reliable topic
      Returns:
      the reliable topic

    • getCluster

      @Nonnull Cluster getCluster()
      Returns the Cluster that this Hazelcast instance is part of. Cluster interface allows you to add a listener for membership events and to learn more about the cluster that this Hazelcast instance is part of.
      Returns:
      the cluster that this Hazelcast instance is part of

    • getLocalEndpoint

      @Nonnull Endpoint getLocalEndpoint()
      Returns the local Endpoint which this HazelcastInstance belongs to.

      Returned endpoint will be a Member instance for cluster nodes and a Client instance for clients.

      Returns:
      the local Endpoint which this HazelcastInstance belongs to
      See Also:

    • getExecutorService

      @Nonnull IExecutorService getExecutorService(@Nonnull String name)
      Creates or returns the distributed executor service for the given name. Executor service enables you to run your Runnables and Callables on the Hazelcast cluster.

      Note: Note that it doesn't support invokeAll/Any and doesn't have standard shutdown behavior

      Parameters:
      name - name of the executor service
      Returns:
      the distributed executor service for the given name

    • getDurableExecutorService

      @Nonnull DurableExecutorService getDurableExecutorService(@Nonnull String name)
      Creates or returns the durable executor service for the given name. DurableExecutor service enables you to run your Runnables and Callables on the Hazelcast cluster.

      Note: Note that it doesn't support invokeAll/Any and doesn't have standard shutdown behavior

      Parameters:
      name - name of the executor service
      Returns:
      the durable executor service for the given name

    • executeTransaction

      <T> T executeTransaction(@Nonnull TransactionalTask<T> task) throws TransactionException
      Executes the given transactional task in current thread using default options and returns the result of the task.
      Type Parameters:
      T - return type of task
      Parameters:
      task - the transactional task to be executed
      Returns:
      result of the transactional task
      Throws:
      TransactionException - if an error occurs during transaction.

    • executeTransaction

      <T> T executeTransaction(@Nonnull TransactionOptions options, @Nonnull TransactionalTask<T> task) throws TransactionException
      Executes the given transactional task in current thread using given options and returns the result of the task.
      Type Parameters:
      T - return type of task
      Parameters:
      options - options for this transactional task
      task - task to be executed
      Returns:
      result of the transactional task
      Throws:
      TransactionException - if an error occurs during transaction.

    • newTransactionContext

      TransactionContext newTransactionContext()
      Creates a new TransactionContext associated with the current thread using default options.
      Returns:
      new TransactionContext associated with the current thread

    • newTransactionContext

      TransactionContext newTransactionContext(@Nonnull TransactionOptions options)
      Creates a new TransactionContext associated with the current thread with given options.
      Parameters:
      options - options for this transaction
      Returns:
      new TransactionContext associated with the current thread

    • getFlakeIdGenerator

      @Nonnull FlakeIdGenerator getFlakeIdGenerator(@Nonnull String name)
      Creates or returns a cluster-wide unique ID generator. Generated IDs are long primitive values and are k-ordered (roughly ordered). IDs are in the range from 0 to Long.MAX_VALUE.

      The IDs contain timestamp component and a node ID component, which is assigned when the member joins the cluster. This allows the IDs to be ordered and unique without any coordination between members, which makes the generator safe even in split-brain scenario (for caveats, see here).

      For more details and caveats, see class documentation for FlakeIdGenerator.

      Parameters:
      name - name of the FlakeIdGenerator
      Returns:
      FlakeIdGenerator for the given name

    • getDistributedObjects

      Collection<DistributedObject> getDistributedObjects()
      Returns all DistributedObjects, that is all maps, queues, topics, locks etc.

      The results are returned on a best-effort basis. The result might miss just-created objects and contain just-deleted objects. An existing object can also be missing from the list occasionally. One cluster member is queried to obtain the list.

      Returns:
      the collection of all instances in the cluster

    • addDistributedObjectListener

      UUID addDistributedObjectListener(@Nonnull DistributedObjectListener distributedObjectListener)
      Adds a Distributed Object listener which will be notified when a new DistributedObject will be created or destroyed.
      Parameters:
      distributedObjectListener - instance listener
      Returns:
      returns registration ID

    • removeDistributedObjectListener

      boolean removeDistributedObjectListener(@Nonnull UUID registrationId)
      Removes the specified Distributed Object listener. Returns silently if the specified instance listener does not exist.
      Parameters:
      registrationId - ID of listener registration
      Returns:
      true if registration is removed, false otherwise

    • getConfig

      @Nonnull Config getConfig()
      Returns the configuration of this Hazelcast instance.
      Returns:
      configuration of this Hazelcast instance

    • getPartitionService

      @Nonnull PartitionService getPartitionService()
      Returns the partition service of this Hazelcast instance. InternalPartitionService allows you to introspect current partitions in the cluster, partition the owner members, and listen for partition migration events.
      Returns:
      the partition service of this Hazelcast instance

    • getSplitBrainProtectionService

      @Nonnull SplitBrainProtectionService getSplitBrainProtectionService()
      Returns the split brain protection service of this Hazelcast instance.

      Split brain protection service can be used to retrieve split brain protection callbacks which let you to notify split brain protection results of your own to the cluster split brain protection service.

      Returns:
      the split brain protection service of this Hazelcast instance

    • getClientService

      @Nonnull ClientService getClientService()
      Returns the client service of this Hazelcast instance. Client service allows you to get information about connected clients.
      Returns:
      the ClientService of this Hazelcast instance.

    • getLoggingService

      @Nonnull LoggingService getLoggingService()
      Returns the logging service of this Hazelcast instance.

      LoggingService allows you to listen for LogEvents generated by Hazelcast runtime. You can log the events somewhere or take action based on the message.

      Returns:
      the logging service of this Hazelcast instance

    • getLifecycleService

      @Nonnull LifecycleService getLifecycleService()
      Returns the lifecycle service for this instance.

      LifecycleService allows you to shutdown this HazelcastInstance and listen for the lifecycle events.

      Returns:
      the lifecycle service for this instance

    • getDistributedObject

      @Nonnull <T extends DistributedObject> T getDistributedObject(@Nonnull String serviceName, @Nonnull String name)
      Type Parameters:
      T - type of the DistributedObject
      Parameters:
      serviceName - name of the service
      name - name of the object
      Returns:
      DistributedObject created by the service

    • getUserContext

      @Nonnull ConcurrentMap<String,Object> getUserContext()
      Returns a ConcurrentMap that can be used to add user-context to the HazelcastInstance. This can be used to store dependencies that otherwise are hard to obtain. HazelcastInstance can be obtained by implementing a HazelcastInstanceAware interface when submitting a Runnable/Callable to Hazelcast ExecutorService. By storing the dependencies in the user-context, they can be retrieved as soon as you have a reference to the HazelcastInstance.

      This structure is purely local and Hazelcast remains agnostic abouts its content.

      Returns:
      a ConcurrentMap that can be used to add user-context to the HazelcastInstance.

    • getXAResource

      @Nonnull HazelcastXAResource getXAResource()
      Gets xaResource which will participate in XATransaction.
      Returns:
      the xaResource

    • getCacheManager

      ICacheManager getCacheManager()
      Obtain the ICacheManager that provides access to JSR-107 (JCache) caches configured on a Hazelcast cluster.

      Note that this method does not return a JCache CacheManager; to obtain a JCache CacheManager use JCache standard API.

      Returns:
      the Hazelcast ICacheManager
      See Also:

    • getCardinalityEstimator

      @Nonnull CardinalityEstimator getCardinalityEstimator(@Nonnull String name)
      Obtain a CardinalityEstimator with the given name.

      The estimator can be used to efficiently estimate the cardinality of unique entities in big data sets, without the need of storing them.

      The estimator is based on a HyperLogLog++ data-structure.

      Parameters:
      name - the name of the estimator
      Returns:
      a CardinalityEstimator

    • getPNCounter

      @Nonnull PNCounter getPNCounter(@Nonnull String name)
      Creates or returns a PNCounter with the given name.

      The PN counter can be used as a counter with strong eventual consistency guarantees - if operations to the counters stop, the counter values of all replicas that can communicate with each other should eventually converge to the same value.

      Parameters:
      name - the name of the PN counter
      Returns:
      a PNCounter

    • getScheduledExecutorService

      @Nonnull IScheduledExecutorService getScheduledExecutorService(@Nonnull String name)
      Creates or returns the IScheduledExecutorService scheduled executor service for the given name. ScheduledExecutor service enables you to schedule your Runnables and Callables on the Hazelcast cluster.
      Parameters:
      name - name of the executor service
      Returns:
      the scheduled executor service for the given name

    • getCPSubsystem

      @Nonnull CPSubsystem getCPSubsystem()
      Returns the CP subsystem that offers a set of in-memory linearizable data structures
      Returns:
      the CP subsystem that offers a set of in-memory linearizable data structures

    • getSql

      @Nonnull SqlService getSql()
      Returns a service to execute distributed SQL queries.
      Returns:
      SQL service
      See Also:

    • getJet

      @Nonnull JetService getJet()
      Returns a Jet service to execute distributed batch and streaming jobs.
      See Also:

    • shutdown

      void shutdown()
      Shuts down this HazelcastInstance. For more information see LifecycleService.shutdown().