Helper methods

The following tables document the helper methods available in Hazelcast. Member methods are available only when the test class inherits the respective support class, hence only in JUnit 4. Static methods can also be used in other frameworks.

Configuration helpers

Method	Static?	Origin	Description
smallInstanceConfig	yes	HazelcastTestSupport	Returns a compact Config with reduced threads but with Jet and metrics enabled.
smallInstanceConfigWithoutJetAndMetrics	yes	HazelcastTestSupport	Returns a compact Config with Jet and metrics disabled and minimal threads.
shrinkInstanceConfig	yes	HazelcastTestSupport	Applies minimal threads, with Jet and metrics enabled, to a given Config.
regularInstanceConfig	yes	HazelcastTestSupport	Returns a default Config with Jet enabled.
withoutNetworkJoin	yes	HazelcastTestSupport	Modifies a given Config to disable all network join mechanisms (TCP/IP and autodetection).

Threading and concurrency utilities

Method	Static?	Origin	Description
spawn	yes	HazelcastTestSupport	Runs a RunnableEx, Runnable, or Callable in a new thread, returning a Future.
interruptCurrentThread	yes	HazelcastTestSupport	Schedules an interrupt of the current thread after a specified delay.

Sleep and timing helpers

Method	Static?	Origin	Description
sleepMillis	yes	HazelcastTestSupport	Sleeps for the specified number of milliseconds, swallowing interruptions.
sleepSeconds	yes	HazelcastTestSupport	Sleeps for the specified number of seconds.
sleepAtMostSeconds	yes	HazelcastTestSupport	Sleeps up to a target end time, warning if already past.
sleepAndStop	yes	HazelcastTestSupport	Sleeps up to a duration unless an AtomicBoolean flag is set, then sets it.
sleepAtLeastMillis	yes	HazelcastTestSupport	Guarantees sleeping at least the given milliseconds, even across interrupts.
sleepAtLeastSeconds	yes	HazelcastTestSupport	Alias in seconds for sleepAtLeastMillis.

Random data and names

Method	Static?	Origin	Description
generateRandomString	yes	HazelcastTestSupport	Builds a random lowercase ASCII string of given length.
randomString	yes	HazelcastTestSupport	Returns a new unsecure UUID string.
randomMapName	yes	HazelcastTestSupport	Returns a random UUID string as a map name (with optional prefix).
randomName	yes	HazelcastTestSupport	Alias for randomString().

Partition and key generation

Method	Static?	Origin	Description
randomNameOwnedBy	yes	HazelcastTestSupport	Generates a random key whose partition is owned by the local member (with optional prefix).
randomPartitionOwnedBy	yes	HazelcastTestSupport	Picks a random partition that is locally owned by a given instance.
generateKeyOwnedBy / generateKeyNotOwnedBy	yes	HazelcastTestSupport	Generates a key owned (or not) by the local member.
generateKeyForPartition	yes	HazelcastTestSupport	Generates a key mapping to a specific partition ID (with optional prefix).
generateKeysBelongingToSamePartitionsOwnedBy	no	HazelcastTestSupport	Generates multiple keys all belonging to the same owned partition.

Partition table and safe-state

Method	Static?	Origin	Description
warmUpPartitions	yes	HazelcastTestSupport	Forces partition table initialization on instances.
isInstanceInSafeState	yes	HazelcastTestSupport	Checks whether a single instance's partition state is safe.
isClusterInSafeState	yes	HazelcastTestSupport	Checks whether the entire cluster is in a safe partition state.
isAllInSafeState	yes	HazelcastTestSupport	Verifies that all instances in a collection are safe.
waitInstanceForSafeState / waitClusterForSafeState / waitAllForSafeState	yes	HazelcastTestSupport	Blocks until instance(s) reach safe state, with retry assertions.
assertAllInSafeState	yes	HazelcastTestSupport	Asserts (throws) if any instance is not in safe state.

Cluster assertions

Method	Static?	Origin	Description
assertNoRunningInstances	yes	HazelcastTestSupport	Asserts that no Hazelcast server instances remain.
assertNoRunningClientInstances	yes	HazelcastTestSupport	Asserts that no Hazelcast client instances remain.
assertClusterSize / assertClusterSizeEventually	yes	HazelcastTestSupport	Asserts cluster size immediately or eventually within timeout.
assertMasterAddress / assertMasterAddressEventually	yes	HazelcastTestSupport	Asserts that all instances agree on the master address.
assertClusterState / assertClusterStateEventually	yes	HazelcastTestSupport	Asserts the cluster state immediately or eventually.

General assertions

Method	Static?	Origin	Description
assertContains / assertNotContains / assertContainsAll / assertNotContainsAll	yes	HazelcastTestSupport	Collection- and string-based containment assertions.
assertStartsWith	yes	HazelcastTestSupport	Asserts that one string starts with another (ComparisonFailure on fail).
assertPropertiesEquals	yes	HazelcastTestSupport	Asserts two Properties objects have identical keys and values.
assertInstanceOf	yes	HazelcastTestSupport	Asserts and casts an object to a given class.
assertIterableEquals	yes	HazelcastTestSupport	Asserts an Iterable yields exactly the expected elements in order.

Time-bound assertions

Method	Static?	Origin	Description
assertCompletesEventually	yes	HazelcastTestSupport	Waits for a Future/FutureTask to complete within timeout.
assertSizeEventually / assertEqualsEventually	yes	HazelcastTestSupport	Waits until collections, maps, or values reach expected state.
assertTrueEventually / assertFalseEventually	yes	HazelcastTestSupport	Retries assertions until success or failure within timeout.
assertTrueDelayed	yes	HazelcastTestSupport	Delays for a fixed period, then asserts.
assertTrueAllTheTime / assertTrueFiveSeconds	yes	HazelcastTestSupport	Continuously asserts a predicate over a duration.
assertCountEventually / assertAtomicEventually	yes	HazelcastTestSupport	Waits for latch or atomic to reach an expected value.

Specialized assertions

Method	Static?	Origin	Description
assertUtilityConstructor	yes	HazelcastTestSupport	Verifies a utility class has exactly one private constructor.
assertEnumCoverage	yes	HazelcastTestSupport	Asserts all enum values are handled via valueOf.
assertThrows	yes	HazelcastTestSupport	Asserts that a given runnable throws a specific exception type.
assertBetween / assertGreaterOrEquals	yes	HazelcastTestSupport	Numeric-range assertions.
assertExactlyOneSuccessfulRun	yes	HazelcastTestSupport	Retries a task until exactly one run succeeds or times out.
assertWaitingOperationCountEventually	yes	HazelcastTestSupport	Waits until the parked operation count reaches an expected value.

Connection and membership

Method	Static?	Origin	Description
closeConnectionBetween	yes	HazelcastTestSupport	Simulates network failure by closing connections between two instances.
suspectMember	yes	HazelcastTestSupport	Marks one node as suspected by another, optionally with a reason.

Reflection and cleanup

Method	Static?	Origin	Description
getFieldValue	yes	HazelcastTestSupport	Reflectively retrieves a private field's value from an object or class.
destroyAllDistributedObjects	yes	HazelcastTestSupport	Iterates over and destroys every DistributedObject on a given instance.

JUnit assumptions

Method	Static?	Origin	Description
assumeThatNoWindowsOS	yes	HazelcastTestSupport	Assumes the test is not running on Windows.
assumeThatLinuxOS	yes	HazelcastTestSupport	Assumes Linux platform.
assumeNoArm64Architecture	yes	HazelcastTestSupport	Assumes non-ARM64 architecture.

File and directory utilities

Method	Static?	Origin	Description
appendToFile	yes	JetTestSupport	Appends one or more lines to an existing file, creating it if needed.
createTempDirectory	yes	JetTestSupport	Creates a temporary directory (deleted on JVM exit) and returns its File.

Jet configuration helpers

Method	Static?	Origin	Description
smallInstanceWithResourceUploadConfig	yes	JetTestSupport	Returns a small default Config with Jet resource-upload enabled.
defaultInstanceConfigWithJetEnabled	yes	JetTestSupport	Returns a default Config with Jet enabled (no thread reduction).

Cluster cleanup and job teardown

Method	Static?	Origin	Description
ditchJob	yes	JetTestSupport	Cancels a job and waits until it is no longer running on any member.
cancelAndJoin	yes	JetTestSupport	Cancels a job and asserts that its join() throws CancellationException.

Pipeline utilities

Method	Static?	Origin	Description
processorFromPipelineSource	yes	JetTestSupport	Extracts the internal ProcessorMetaSupplier from a BatchSource pipeline stage.
awaitSingleRunningJob	yes	JetTestSupport	Waits until exactly one Jet job is in RUNNING state and returns it.

TestHazelcastFactory utilities

Method	Static?	Origin	Description
getCount	no	TestHazelcastInstanceFactory	Returns the configured number of nodes/addresses.
newHazelcastInstance	no	TestHazelcastInstanceFactory	Creates a new server instance using default or mock-network context. Various overloads available.
createAddressOrNull	yes	TestHazelcastInstanceFactory	Attempts to build an Address, returning null on UnknownHostException.
nextAddress()	no	TestHazelcastInstanceFactory	Returns the next pre-allocated or newly minted Address on default port.
nextAddress(int)	no	TestHazelcastInstanceFactory	Returns the next Address starting at a given initial port.
newInstances	no	TestHazelcastInstanceFactory	Creates as many instances as count using default or provided Config. Various overloads available.
newInstancesParallel	no	TestHazelcastInstanceFactory	Creates nodeCount instances in parallel, each with its own address and config.
getAllHazelcastInstances	no	TestHazelcastInstanceFactory	Returns all live instances, mock-network or real.
getKnownAddresses	no	TestHazelcastInstanceFactory	Returns the unmodifiable list of all addresses this factory manages.
terminate(HazelcastInstance)	no	TestHazelcastInstanceFactory	Terminates one instance and removes it from registry if mock-network.
shutdownAll()	no	TestHazelcastInstanceFactory	Shuts down all instances; clears registry or calls Hazelcast.shutdownAll().
terminateAll()	no	TestHazelcastInstanceFactory	Terminates all instances; stops registry or calls HazelcastInstanceFactory.terminateAll().
newHazelcastClient	no	TestHazelcastFactory	Creates a new client in the mock-network setup. Various overloads available.
getHazelcastClientByName(String)	no	TestHazelcastFactory	Retrieves a previously created client proxy by its name.
shutdownAllMembers()	no	TestHazelcastFactory	Shuts down all server members via parent shutdownAll().
shutdownAll()	no	TestHazelcastFactory	Shuts down all clients (mock-network or real) then all members.
terminateAll()	no	TestHazelcastFactory	Terminates all clients then all members.