org.apache.jackrabbit.oak.segment.file.cancel

Class Canceller

java.lang.Object

org.apache.jackrabbit.oak.segment.file.cancel.Canceller

public class Canceller
extends Object

Represents a way to check for a cancellation request. Users of this class (possibly cancelable, long-running operations) should periodically check whether a cancellation request has been received.

Method Summary

Modifier and Type	Method and Description
Cancellation	check() Check if cancellation has been requested.
static Canceller	newCanceller() Create a new Canceller which is trivially empty.
Canceller	withCondition(String reason, BooleanSupplier condition) Return a new Canceller based on a boolean predicate.
Canceller	withShortCircuit() Create a new Canceller based on this Canceller.
Canceller	withTimeout(String reason, long duration, TimeUnit unit) Return a new Canceller based on time duration.

Methods inherited from class java.lang.Object

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

Method Detail

newCanceller

public static Canceller newCanceller()

Create a new Canceller which is trivially empty. The returned Canceller will never relay a positive cancellation request.

Returns:

an instance of Canceller.

check

public Cancellation check()

Check if cancellation has been requested. This method should be invoked periodically, and the returned Cancellation should be inspected and reacted upon.

Returns:

an instance of Cancellation.

withCondition

public Canceller withCondition(String reason,
                               BooleanSupplier condition)

Return a new Canceller based on a boolean predicate. The returned instance will relay a positive cancellation request when either the supplied boolean predicate is true or this Canceller is cancelled.

Parameters:

reason - The reason associated to the boolean condition.

condition - A boolean predicate.

Returns:

a new instance of Canceller.

withTimeout

public Canceller withTimeout(String reason,
                             long duration,
                             TimeUnit unit)

Return a new Canceller based on time duration. The returned instance will relay a positive cancellation request when either the duration expires or this Canceller is cancelled.

Parameters:

reason - The reason associated to the boolean condition.

duration - The duration for the timeout.

unit - The time unit for the duration.

Returns:

a new instance of Canceller.

withShortCircuit

public Canceller withShortCircuit()

Create a new Canceller based on this Canceller. The returned instance will be canceled when this instance is canceled, but will never transition back to an "uncanceled" state.

Returns:

an new instance of Canceller.