Package org.apache.flink.runtime.state

Class StateUtil

java.lang.Object

org.apache.flink.runtime.state.StateUtil

public class StateUtil
extends Object

Helpers for StateObject related code.

Method Summary

Modifier and Type	Method	Description
static void	bestEffortDiscardAllStateObjects(Iterable<? extends StateObject> handlesToDiscard)	Iterates through the passed state handles and calls discardState() on each handle that is not null.
static org.apache.flink.api.java.tuple.Tuple2<Long,Long>	discardStateFuture(Future<? extends StateObject> stateFuture)	Discards the given state future by first trying to cancel it.
static void	discardStateObjectQuietly(StateObject stateObject)
static long	getStateSize(StateObject handle)	Returns the size of a state object.
static RuntimeException	unexpectedStateHandleException(Class<? extends StateObject>[] expectedStateHandleClasses, Class<? extends StateObject> actualStateHandleClass)	Creates a RuntimeException that signals that an operation did not get the type of StateObject that was expected.
static RuntimeException	unexpectedStateHandleException(Class<? extends StateObject> expectedStateHandleClass, Class<? extends StateObject> actualStateHandleClass)	Creates an RuntimeException that signals that an operation did not get the type of StateObject that was expected.

Methods inherited from class java.lang.Object

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

Method Details

getStateSize

public static long getStateSize(StateObject handle)

Returns the size of a state object.

Parameters:

handle - The handle to the retrieved state

bestEffortDiscardAllStateObjects

public static void bestEffortDiscardAllStateObjects(Iterable<? extends StateObject> handlesToDiscard)
                                             throws Exception

Iterates through the passed state handles and calls discardState() on each handle that is not null. All occurring exceptions are suppressed and collected until the iteration is over and emitted as a single exception.

Parameters:

handlesToDiscard - State handles to discard. Passed iterable is allowed to deliver null values.

Throws:

Exception - exception that is a collection of all suppressed exceptions that were caught during iteration

discardStateObjectQuietly

public static void discardStateObjectQuietly(StateObject stateObject)

discardStateFuture

public static org.apache.flink.api.java.tuple.Tuple2<Long,Long> discardStateFuture(Future<? extends StateObject> stateFuture)
                                                                            throws Exception

Discards the given state future by first trying to cancel it. If this is not possible, then the state object contained in the future is calculated and afterwards discarded.

Parameters:

stateFuture - to be discarded

Returns:

the size of state before cancellation (if available)

Throws:

Exception - if the discard operation failed

unexpectedStateHandleException

public static RuntimeException unexpectedStateHandleException(Class<? extends StateObject> expectedStateHandleClass,
 Class<? extends StateObject> actualStateHandleClass)

Creates an RuntimeException that signals that an operation did not get the type of StateObject that was expected. This can mostly happen when a different StateBackend from the one that was used for taking a checkpoint/savepoint is used when restoring.

unexpectedStateHandleException

public static RuntimeException unexpectedStateHandleException(Class<? extends StateObject>[] expectedStateHandleClasses,
 Class<? extends StateObject> actualStateHandleClass)

Creates a RuntimeException that signals that an operation did not get the type of StateObject that was expected. This can mostly happen when a different StateBackend from the one that was used for taking a checkpoint/savepoint is used when restoring.