Package com.illumon.iris.db.v2.locations

Class TableLocationProvider.Null

java.lang.Object

com.illumon.iris.db.v2.locations.TableLocationProvider.Null

All Implemented Interfaces:

com.fishlib.base.log.LogOutputAppendable, TableKey, TableLocationProvider, NamedImplementation

Enclosing interface:

TableLocationProvider

public static class TableLocationProvider.Null
extends Object
implements TableLocationProvider

This is a fully functional TableLocationProvider that will not provide any locations. It can be used as a placeholder to block access to TableLocations in a TableDataService.

Nested Class Summary

Nested classes/interfaces inherited from interface com.illumon.iris.db.v2.locations.TableKey

TableKey.KeyedObjectKeyImpl<VALUE_TYPE>, TableKey.SelfKeyedObjectKeyImpl<VALUE_TYPE extends TableKey>

Nested classes/interfaces inherited from interface com.illumon.iris.db.v2.locations.TableLocationProvider

TableLocationProvider.Listener, TableLocationProvider.Null

Field Summary

Fields inherited from interface com.illumon.iris.db.v2.locations.TableKey

NULL_NAME

Fields inherited from interface com.illumon.iris.db.v2.locations.TableLocationProvider

globalMark

Constructor Summary

Constructors

Constructor	Description
Null(TableKey key)

Method Summary

Modifier and Type	Method	Description
TableLocationProvider	ensureInitialized()	Ensure that this location provider is initialized.
CharSequence	getNamespace()
TableLocation	getTableLocationIfPresent(TableLocationKey tableLocationKey)
Collection<TableLocation>	getTableLocations()	Get this provider's currently available locations.
CharSequence	getTableName()
TableType	getTableType()
void	mark(long mark)	Indicate the start of a sweep of locations.
void	refresh()	Initialize or refresh state information about the list of existing locations.
void	removeTableLocationKey(TableLocationKey locationKey)	Remove the given table location from the tableLocations map.
boolean	removeUnvisited(long mark)	Removes any locations that were not visited after the given mark time.
void	subscribe(TableLocationProvider.Listener listener)	Subscribe to pushed location additions.
boolean	supportsSubscriptions()	Does this provider support subscriptions? That is, can this provider ever have ticking data?
void	unsubscribe(TableLocationProvider.Listener listener)	Unsubscribe from pushed location additions.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.illumon.util.type.NamedImplementation

getImplementationName

Methods inherited from interface com.illumon.iris.db.v2.locations.TableKey

append, asTableIdentifier, toStringDetailed, toStringHelper, toStringSimple, writeTo

Methods inherited from interface com.illumon.iris.db.v2.locations.TableLocationProvider

getName, getTableLocation, getTableLocation, refreshAndRescan, refreshAndRescan

Constructor Details

Null

public Null(@NotNull TableKey key)

Method Details

getNamespace

@NotNull public CharSequence getNamespace()

Specified by:

getNamespace in interface TableKey

Returns:

The namespace enclosing this table

getTableName

@NotNull public CharSequence getTableName()

Specified by:

getTableName in interface TableKey

Returns:

The name of this table

getTableType

@NotNull public TableType getTableType()

Specified by:

getTableType in interface TableKey

Returns:

The type of this table (which generally dictates storage, metadata-availability, etc)

mark

public void mark(long mark)

Description copied from interface: TableLocationProvider

Indicate the start of a sweep of locations. This will be used to detect locations that have been removed from downstream.

Specified by:

mark in interface TableLocationProvider

Parameters:

mark - the value to set

removeUnvisited

public boolean removeUnvisited(long mark)

Description copied from interface: TableLocationProvider

Removes any locations that were not visited after the given mark time.

Specified by:

removeUnvisited in interface TableLocationProvider

Parameters:

mark - any locations last visited before this mark will be removed.

Returns:

true if any locations were removed.

supportsSubscriptions

public boolean supportsSubscriptions()

Description copied from interface: TableLocationProvider

Does this provider support subscriptions? That is, can this provider ever have ticking data?

Specified by:

supportsSubscriptions in interface TableLocationProvider

Returns:

True if this provider supports subscriptions.

subscribe

public void subscribe(@NotNull TableLocationProvider.Listener listener)

Description copied from interface: TableLocationProvider

Subscribe to pushed location additions. Subscribing more than once with the same listener without an intervening unsubscribe is an error, and may result in undefined behavior.

This is a possibly asynchronous operation - listener will receive 0 or more handleTableLocation callbacks, followed by 0 or 1 handleException callbacks during invocation and continuing after completion, on a thread determined by the implementation. As noted in BasicTableDataListener.handleException(TableDataException), an exception callback signifies that the subscription is no longer valid, and no unsubscribe is required in that case. Callers must not hold any lock that prevents notification delivery while subscribing. Callers must guard against duplicate notifications.

This method only guarantees eventually consistent state. To force a state update, use refresh() after subscription completes.

Specified by:

subscribe in interface TableLocationProvider

Parameters:

listener - A listener.

unsubscribe

public void unsubscribe(@NotNull TableLocationProvider.Listener listener)

Description copied from interface: TableLocationProvider

Unsubscribe from pushed location additions.

Specified by:

unsubscribe in interface TableLocationProvider

Parameters:

listener - The listener to forget about.

refresh

public void refresh()

Description copied from interface: TableLocationProvider

Initialize or refresh state information about the list of existing locations.

Specified by:

refresh in interface TableLocationProvider

ensureInitialized

public TableLocationProvider ensureInitialized()

Description copied from interface: TableLocationProvider

Ensure that this location provider is initialized. Mainly useful in cases where it cannot be otherwise guaranteed that TableLocationProvider.refresh() or TableLocationProvider.subscribe(Listener) has been called prior to calls to the various table location fetch methods.

Specified by:

ensureInitialized in interface TableLocationProvider

Returns:

this, to allow method chaining

getTableLocations

@NotNull public Collection<TableLocation> getTableLocations()

Description copied from interface: TableLocationProvider

Get this provider's currently available locations. Locations returned may have null size - that is, they may not "exist" for application purposes.

Specified by:

getTableLocations in interface TableLocationProvider

Returns:

A collection of locations available from this provider

getTableLocationIfPresent

@Nullable public TableLocation getTableLocationIfPresent(@NotNull TableLocationKey tableLocationKey)

Specified by:

getTableLocationIfPresent in interface TableLocationProvider

Parameters:

tableLocationKey - A key specifying the location to get

Returns:

The TableLocation matching the given key if present, else null

removeTableLocationKey

public void removeTableLocationKey(@NotNull TableLocationKey locationKey)

Description copied from interface: TableLocationProvider

Remove the given table location from the tableLocations map. Use with caution: the intent is that when a TableLocationProvider is told that a location is gone, we should quit providing it in the list of locations, and quit asking downstream providers how big it is.

Specified by:

removeTableLocationKey in interface TableLocationProvider

Parameters:

locationKey - the TableLocation to remove