Package io.axoniq.framework.messaging.deadletter

Class GenericDeadLetter<M extends Message>

java.lang.Object

io.axoniq.framework.messaging.deadletter.GenericDeadLetter<M>

Type Parameters:

M - the message type

All Implemented Interfaces:

DeadLetter<M>

public class GenericDeadLetter<M extends Message>
extends Object
implements DeadLetter<M>

Generic implementation of the dead letter allowing any type of Message to be dead lettered.

Since:

4.6.0

Author:

Steven van Beelen, Mitchell Herrijgers

Field Summary

Fields

Modifier and Type	Field	Description
static Clock	clock	Clock instance used to set the DeadLetter.enqueuedAt() and DeadLetter.lastTouched() times on dead letters.

Fields inherited from interface io.axoniq.framework.messaging.deadletter.DeadLetter

RESOURCE_KEY

Constructor Summary

Constructors

Constructor	Description
GenericDeadLetter(Object sequenceIdentifier, M message)	Construct a GenericDeadLetter with the given sequenceIdentifier and message.
GenericDeadLetter(Object sequenceIdentifier, M message, @Nullable Cause cause, Instant enqueuedAt, Instant lastTouched, Metadata diagnostics)	Construct a GenericDeadLetter defining all the fields.
GenericDeadLetter(Object sequenceIdentifier, M message, @Nullable Cause cause, Instant enqueuedAt, Instant lastTouched, Metadata diagnostics, Context context)	Construct a GenericDeadLetter defining all the fields including the associated Context.
GenericDeadLetter(Object sequenceIdentifier, M message, @Nullable Throwable cause)	Construct a GenericDeadLetter with the given sequenceIdentifier, message, and cause.
GenericDeadLetter(Object sequenceIdentifier, M message, @Nullable Throwable cause, Context context)	Construct a GenericDeadLetter with the given sequenceIdentifier, message, cause, and associated Context.

Method Summary

Modifier and Type	Method	Description
Optional<Cause>	cause()	The cause for the DeadLetter.message() to be dead lettered.
Context	context()	Returns the Context associated with this dead letter, carrying resources that were present in the ProcessingContext when the letter was enqueued.
Metadata	diagnostics()	The diagnostic Metadata concerning this letter.
Instant	enqueuedAt()	The moment in time when the DeadLetter.message() was entered in a dead letter queue.
boolean	equals(Object o)
Object	getSequenceIdentifier()	Returns the sequence identifier of the sequence this message() belongs to.
int	hashCode()
Instant	lastTouched()	The moment in time when this letter was last touched.
DeadLetter<M>	markTouched()	Construct a copy of this DeadLetter, replacing the DeadLetter.lastTouched() with the current time.
M	message()	The Message of type M contained in this letter.
String	toString()
DeadLetter<M>	withCause(Throwable requeueCause)	Construct a copy of this DeadLetter, replacing the DeadLetter.cause() with the given requeueCause.
DeadLetter<M>	withDiagnostics(Metadata diagnostics)	Construct a copy of this DeadLetter, replacing the DeadLetter.diagnostics() with the given diagnostics.

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.axoniq.framework.messaging.deadletter.DeadLetter

position, withDiagnostics

Field Details

clock

public static Clock clock

Clock instance used to set the DeadLetter.enqueuedAt() and DeadLetter.lastTouched() times on dead letters. Can be adjusted to alter the desired time(zone) of those fields.

Constructor Details

GenericDeadLetter

public GenericDeadLetter(Object sequenceIdentifier,
 M message)

Construct a GenericDeadLetter with the given sequenceIdentifier and message. The cause() is left empty in this case. This method is typically used to construct a dead letter that's part of a sequence.

Parameters:

sequenceIdentifier - the sequence identifier of the GenericDeadLetter to build

message - the Message of type M of the GenericDeadLetter to build

GenericDeadLetter

public GenericDeadLetter(Object sequenceIdentifier,
 M message,
 @Nullable Throwable cause)

Construct a GenericDeadLetter with the given sequenceIdentifier, message, and cause. This method is typically used to construct the first dead letter entry for the given queueIdentifier.

Parameters:

sequenceIdentifier - the sequence identifier of the GenericDeadLetter to build

message - the Message of type M of the GenericDeadLetter to build

cause - the cause for the message to be dead lettered

GenericDeadLetter

public GenericDeadLetter(Object sequenceIdentifier,
 M message,
 @Nullable Throwable cause,
 Context context)

Construct a GenericDeadLetter with the given sequenceIdentifier, message, cause, and associated Context.

Parameters:

sequenceIdentifier - the sequence identifier of the GenericDeadLetter to build

message - the Message of type M of the GenericDeadLetter to build

cause - the cause for the message to be dead lettered

context - the Context associated with this dead letter

GenericDeadLetter

public GenericDeadLetter(Object sequenceIdentifier,
 M message,
 @Nullable Cause cause,
 Instant enqueuedAt,
 Instant lastTouched,
 Metadata diagnostics)

Construct a GenericDeadLetter defining all the fields. The Context defaults to Context.empty().

Parameters:

sequenceIdentifier - the sequence identifier of the GenericDeadLetter to build

message - the Message of type M of the GenericDeadLetter to build

cause - the cause for the message to be dead lettered

enqueuedAt - the moment this dead letter is enqueued

lastTouched - the last time this dead letter was touched

diagnostics - the diagnostic Metadata of this dead letter

GenericDeadLetter

public GenericDeadLetter(Object sequenceIdentifier,
 M message,
 @Nullable Cause cause,
 Instant enqueuedAt,
 Instant lastTouched,
 Metadata diagnostics,
 Context context)

Construct a GenericDeadLetter defining all the fields including the associated Context.

Parameters:

sequenceIdentifier - the sequence identifier of the GenericDeadLetter to build

message - the Message of type M of the GenericDeadLetter to build

cause - the cause for the message to be dead lettered

enqueuedAt - the moment this dead letter is enqueued

lastTouched - the last time this dead letter was touched

diagnostics - the diagnostic Metadata of this dead letter

context - the Context associated with this dead letter

Method Details

message

public M message()

Description copied from interface: DeadLetter

The Message of type M contained in this letter.

Specified by:

message in interface DeadLetter<M extends Message>

Returns:

the Message of type M contained in this letter

cause

public Optional<Cause> cause()

Description copied from interface: DeadLetter

The cause for the DeadLetter.message() to be dead lettered. Can be an Optional.empty() in case this letter is enqueued without a causal error. For instance, when another letter already present in the queue was blocking it being handled.

Specified by:

cause in interface DeadLetter<M extends Message>

Returns:

the cause for the DeadLetter.message() to be dead lettered

enqueuedAt

public Instant enqueuedAt()

Description copied from interface: DeadLetter

The moment in time when the DeadLetter.message() was entered in a dead letter queue.

Specified by:

enqueuedAt in interface DeadLetter<M extends Message>

Returns:

the moment in time when the DeadLetter.message() was entered in a dead letter queue

lastTouched

public Instant lastTouched()

Description copied from interface: DeadLetter

The moment in time when this letter was last touched. Will equal the DeadLetter.enqueuedAt() value if this letter is enqueued for the first time.

Specified by:

lastTouched in interface DeadLetter<M extends Message>

Returns:

the moment in time when this letter was last touched

diagnostics

public Metadata diagnostics()

Description copied from interface: DeadLetter

The diagnostic Metadata concerning this letter.

Specified by:

diagnostics in interface DeadLetter<M extends Message>

Returns:

the diagnostic Metadata concerning this letter

context

public Context context()

Description copied from interface: DeadLetter

Returns the Context associated with this dead letter, carrying resources that were present in the ProcessingContext when the letter was enqueued. Defaults to Context.empty() if not overridden.

The following resources are stored and restored through this context:

• TrackingToken.RESOURCE_KEY: always present when the letter was enqueued by a streaming event processor.
• LegacyResources.AGGREGATE_TYPE_KEY, LegacyResources.AGGREGATE_IDENTIFIER_KEY, and LegacyResources.AGGREGATE_SEQUENCE_NUMBER_KEY, present only when the event was stored by an aggregate-based event storage engine.

Specified by:

context in interface DeadLetter<M extends Message>

Returns:

the Context associated with this dead letter

markTouched

public DeadLetter<M> markTouched()

Description copied from interface: DeadLetter

Construct a copy of this DeadLetter, replacing the DeadLetter.lastTouched() with the current time.

Specified by:

markTouched in interface DeadLetter<M extends Message>

Returns:

a copy of this DeadLetter with DeadLetter.lastTouched() set to now

withCause

public DeadLetter<M> withCause(Throwable requeueCause)

Description copied from interface: DeadLetter

Construct a copy of this DeadLetter, replacing the DeadLetter.cause() with the given requeueCause.

Specified by:

withCause in interface DeadLetter<M extends Message>

Parameters:

requeueCause - the new cause of the DeadLetter under construction

Returns:

a copy of this DeadLetter, replacing the DeadLetter.cause() with the given requeueCause

withDiagnostics

public DeadLetter<M> withDiagnostics(Metadata diagnostics)

Description copied from interface: DeadLetter

Construct a copy of this DeadLetter, replacing the DeadLetter.diagnostics() with the given diagnostics.

Specified by:

withDiagnostics in interface DeadLetter<M extends Message>

Parameters:

diagnostics - the diagnostic Metadata to append to the DeadLetter under construction

Returns:

a copy of this DeadLetter, replacing the DeadLetter.diagnostics() with the given diagnostics

getSequenceIdentifier

public Object getSequenceIdentifier()

Returns the sequence identifier of the sequence this message() belongs to.

Returns:

The sequence identifier of the sequence this message() belongs to.

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