com.netflix.hollow.api.producer

Class HollowProducer.Incremental

java.lang.Object

com.netflix.hollow.api.producer.HollowProducer.Incremental

Enclosing class:

HollowProducer

public static class HollowProducer.Incremental
extends java.lang.Object

A producer of Hollow data that populates with given data changes (addition, modification or removal), termed incremental production.

A HollowProducer populates with all the given data after which changes are determined. Generally in other respects HollowProducer and HollowProducer.Incremental have the same behaviour when publishing and announcing data states.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	HollowProducer.Incremental.IncrementalPopulator Represents a task that incrementally populates a new data state within a HollowProducer cycle ( more specifically within the population stage)
static interface	HollowProducer.Incremental.IncrementalWriteState Representation of write state that can be incrementally changed.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Incremental(HollowProducer.Builder<?> b)

Method Summary

Modifier and Type	Method and Description
void	addListener(HollowProducerEventListener listener) Adds a listener to this producer.
void	addListener(HollowProducerListener listener) Adds a listener to this producer.
boolean	enablePrimaryProducer(boolean doEnable) Invoke this method to alter runCycle behavior.
HollowProducerMetrics	getMetrics()
HollowObjectMapper	getObjectMapper()
HollowWriteStateEngine	getWriteEngine()
void	initializeDataModel(java.lang.Class<?>... classes) Initializes the data model for the given classes.
void	initializeDataModel(HollowSchema... schemas) Initializes the producer data model for the given schemas.
void	removeListener(HollowProducerEventListener listener) Removes a listener to this producer.
void	removeListener(HollowProducerListener listener) Removes a listener to this producer.
HollowProducer.ReadState	restore(long versionDesired, HollowConsumer.BlobRetriever blobRetriever) Restores the data state to a desired version.
long	runIncrementalCycle(HollowProducer.Incremental.IncrementalPopulator task) Runs a cycle to incrementally populate, publish, and announce a new single data state.

Methods inherited from class java.lang.Object

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

Constructor Detail

Incremental

protected Incremental(HollowProducer.Builder<?> b)

Method Detail

restore

public HollowProducer.ReadState restore(long versionDesired,
                                        HollowConsumer.BlobRetriever blobRetriever)

Restores the data state to a desired version.

Data model initialization is required prior to restoring the producer. This ensures that restoration can correctly compare the producer's current data model with the data model of the restored data state and manage any differences in those models (such as not restoring state for any types in the restoring data model not present in the producer's current data model)

Parameters:

versionDesired - the desired version

blobRetriever - the blob retriever

Returns:

the read state of the restored state

Throws:

java.lang.IllegalStateException - if the producer's data model has not been initialized

See Also:

initializeDataModel(Class[])

runIncrementalCycle

public long runIncrementalCycle(HollowProducer.Incremental.IncrementalPopulator task)

Runs a cycle to incrementally populate, publish, and announce a new single data state.

Parameters:

task - the incremental populating task to add changes (additions, modifications, or deletions)

Returns:

the version identifier of the announced state, otherwise the last successful announced version if 1) there were no data changes compared to that version; or 2) the producer is not the primary producer

Throws:

java.lang.RuntimeException - if the cycle failed

getMetrics

public HollowProducerMetrics getMetrics()

Returns:

the metrics for this producer

initializeDataModel

public void initializeDataModel(java.lang.Class<?>... classes)

Initializes the data model for the given classes.

Data model initialization is required prior to restoring the producer. This ensures that restoration can correctly compare the producer's current data model with the data model of the restored data state and manage any differences in those models (such as not restoring state for any types in the restoring data model not present in the producer's current data model).

After initialization a data model initialization event will be emitted to all registered data model initialization listeners listeners.

Parameters:

classes - the data model classes

Throws:

java.lang.IllegalArgumentException - if classes is empty

See Also:

restore(long, HollowConsumer.BlobRetriever)

initializeDataModel

public void initializeDataModel(HollowSchema... schemas)

Initializes the producer data model for the given schemas.

Data model initialization is required prior to restoring the producer. This ensures that restoration can correctly compare the producer's current data model with the data model of the restored data state and manage any differences in those models (such as not restoring state for any types in the restoring data model not present in the producer's current data model).

After initialization a data model initialization event will be emitted to all registered data model initialization listeners listeners.

Parameters:

schemas - the data model classes

Throws:

java.lang.IllegalArgumentException - if schemas is empty

See Also:

restore(long, HollowConsumer.BlobRetriever)

getWriteEngine

public HollowWriteStateEngine getWriteEngine()

getObjectMapper

public HollowObjectMapper getObjectMapper()

enablePrimaryProducer

public boolean enablePrimaryProducer(boolean doEnable)

Invoke this method to alter runCycle behavior. If this Producer is not primary, runCycle is a no-op. Note that by default, SingleProducerEnforcer is instantiated as BasicSingleProducerEnforcer, which is initialized to return true for isPrimary()

Parameters:

doEnable - true if enable primary producer, if false

Returns:

true if the intended action was successful

addListener

public void addListener(HollowProducerListener listener)

Adds a listener to this producer.

If the listener was previously added to this consumer, as determined by reference equality or Object equality, then this method does nothing.

If a listener is added, concurrently, during the occurrence of a cycle or restore then the listener will not receive events until the next cycle or restore. The listener may also be removed concurrently.

Parameters:

listener - the listener to add

addListener

public void addListener(HollowProducerEventListener listener)

Adds a listener to this producer.

If the listener was previously added to this consumer, as determined by reference equality or Object equality, then this method does nothing.

If a listener is added, concurrently, during the occurrence of a cycle or restore then the listener will not receive events until the next cycle or restore. The listener may also be removed concurrently.

Parameters:

listener - the listener to add

removeListener

public void removeListener(HollowProducerListener listener)

Removes a listener to this producer.

If the listener was not previously added to this producer, as determined by reference equality or Object equality, then this method does nothing.

If a listener is removed, concurrently, during the occurrence of a cycle or restore then the listener will receive all events for that cycle or restore but not receive events for a subsequent cycle or restore.

Parameters:

listener - the listener to remove

removeListener

public void removeListener(HollowProducerEventListener listener)

Removes a listener to this producer.

If the listener was not previously added to this producer, as determined by reference equality or Object equality, then this method does nothing.

If a listener is removed, concurrently, during the occurrence of a cycle or restore then the listener will receive all events for that cycle or restore but not receive events for a subsequent cycle or restore.

Parameters:

listener - the listener to remove