org.axonframework.eventhandling

Class ReplayToken

java.lang.Object

org.axonframework.eventhandling.ReplayToken

All Implemented Interfaces:

Serializable, TrackingToken, WrappedToken

public class ReplayToken
extends Object
implements TrackingToken, WrappedToken, Serializable

Token keeping track of the position before a reset was triggered. This allows for downstream components to detect messages that are redelivered as part of a replay.

Since:

3.2

Author:

Allard Buijze

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ReplayToken(TrackingToken tokenAtReset) Initialize a ReplayToken, using the given tokenAtReset to represent the position at which a reset was triggered.
ReplayToken(TrackingToken tokenAtReset, TrackingToken newRedeliveryToken) Initializes a ReplayToken with tokenAtReset which represents the position at which a reset was triggered and the newRedeliveryToken which represents current token.

Method Summary

Modifier and Type	Method and Description
TrackingToken	advancedTo(TrackingToken newToken) Advance this token to the given newToken.
boolean	covers(TrackingToken other) Indicates whether this token covers the other token completely.
static TrackingToken	createReplayToken(TrackingToken tokenAtReset) Creates a new TrackingToken that represents the tail position of a stream, in reset state, when appropriate.
static TrackingToken	createReplayToken(TrackingToken tokenAtReset, TrackingToken startPosition) Creates a new TrackingToken that represents the given startPosition of a stream, in reset state, when appropriate.
boolean	equals(Object o)
TrackingToken	getCurrentToken() Gets the current token.
TrackingToken	getTokenAtReset() Gets the token representing the position at which the reset was triggered.
int	hashCode()
static boolean	isReplay(Message<?> message) Indicates whether the given message is "redelivered", as a result of a previous reset.
static boolean	isReplay(TrackingToken trackingToken) Indicates whether the given trackingToken represents a position that is part of a replay.
TrackingToken	lowerBound(TrackingToken other) Returns a token that represents the lower bound between this and the other token.
String	toString()
TrackingToken	unwrap() Returns the token representing the current position in the stream.
TrackingToken	upperBound(TrackingToken other) Returns the token that represents the furthest possible position in a stream that either this token or the given other represents.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ReplayToken

public ReplayToken(TrackingToken tokenAtReset)

Initialize a ReplayToken, using the given tokenAtReset to represent the position at which a reset was triggered. The current token is reset to the initial position.

Using the createReplayToken(TrackingToken) is preferred, as it covers cases where a replay is started

Parameters:

tokenAtReset - The token representing the position at which the reset was triggered.

ReplayToken

public ReplayToken(TrackingToken tokenAtReset,
                   TrackingToken newRedeliveryToken)

Initializes a ReplayToken with tokenAtReset which represents the position at which a reset was triggered and the newRedeliveryToken which represents current token.

Parameters:

tokenAtReset - The token representing the position at which the reset was triggered

newRedeliveryToken - The current token

Method Detail

createReplayToken

public static TrackingToken createReplayToken(TrackingToken tokenAtReset,
                                              TrackingToken startPosition)

Creates a new TrackingToken that represents the given startPosition of a stream, in reset state, when appropriate.

Parameters:

tokenAtReset - The token present when the reset was triggered

startPosition - The position where the token should be reset to

Returns:

A token that represents a reset to the tail of the stream

createReplayToken

public static TrackingToken createReplayToken(TrackingToken tokenAtReset)

Creates a new TrackingToken that represents the tail position of a stream, in reset state, when appropriate.

Parameters:

tokenAtReset - The token present when the reset was triggered

Returns:

A token that represents a reset to the tail of the stream

isReplay

public static boolean isReplay(Message<?> message)

Indicates whether the given message is "redelivered", as a result of a previous reset. If true, this means this message has been delivered to this processor before its token was reset.

Parameters:

message - The message to inspect

Returns:

true if the message is a replay

isReplay

public static boolean isReplay(TrackingToken trackingToken)

Indicates whether the given trackingToken represents a position that is part of a replay.

Parameters:

trackingToken - The token to verify

Returns:

true if the token indicates a replay

getTokenAtReset

public TrackingToken getTokenAtReset()

Gets the token representing the position at which the reset was triggered.

Returns:

the token representing the position at which the reset was triggered

getCurrentToken

public TrackingToken getCurrentToken()

Gets the current token.

Returns:

the current token

advancedTo

public TrackingToken advancedTo(TrackingToken newToken)

Advance this token to the given newToken.

Parameters:

newToken - The token representing the position to advance to

Returns:

a token representing the new position

lowerBound

public TrackingToken lowerBound(TrackingToken other)

Description copied from interface: TrackingToken

Returns a token that represents the lower bound between this and the other token. Effectively, the returned token will cause messages not received by both this and the other token to be redelivered.

Specified by:

lowerBound in interface TrackingToken

Parameters:

other - The token to compare to this one

Returns:

The token representing the lower bound of the two

upperBound

public TrackingToken upperBound(TrackingToken other)

Description copied from interface: TrackingToken

Returns the token that represents the furthest possible position in a stream that either this token or the given other represents. Effectively, this means this token will only deliver messages that neither this, nor the other have been received.

Specified by:

upperBound in interface TrackingToken

Parameters:

other - The token to compare this token to

Returns:

a token that represents the furthest position of this or the other stream

covers

public boolean covers(TrackingToken other)

Description copied from interface: TrackingToken

Indicates whether this token covers the other token completely. That means that this token represents a position in a stream that has received all of the messages that a stream represented by the other token has received.

Specified by:

covers in interface TrackingToken

Parameters:

other - The token to compare to this one

Returns:

true if this token covers the other, otherwise false

unwrap

public TrackingToken unwrap()

Description copied from interface: WrappedToken

Returns the token representing the current position in the stream.

Specified by:

unwrap in interface WrappedToken

Returns:

the token representing the current position in the stream

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object