Package io.deephaven.engine.table.impl.locations.impl

Class SingleTableLocationProvider

java.lang.Object

io.deephaven.engine.table.impl.locations.impl.SingleTableLocationProvider

All Implemented Interfaces:

TableLocationProvider, NamedImplementation

public final class SingleTableLocationProvider
extends Object
implements TableLocationProvider

A TableLocationProvider that provides access to exactly one, previously-known TableLocation.

Nested Class Summary

Nested classes/interfaces inherited from interface io.deephaven.engine.table.impl.locations.TableLocationProvider

TableLocationProvider.Listener

Constructor Summary

Constructors

Constructor	Description
SingleTableLocationProvider(@NotNull TableLocation tableLocation)

Method Summary

Modifier and Type	Method	Description
TableLocationProvider	ensureInitialized()	Ensure that this location provider is initialized.
String	getImplementationName()	Get a name for the implementing class.
ImmutableTableKey	getKey()	Get the TableKey associated with this provider.
@Nullable TableLocation	getTableLocationIfPresent(@NotNull TableLocationKey tableLocationKey)
@NotNull Collection<ImmutableTableLocationKey>	getTableLocationKeys()	Get this provider's currently known location keys.
boolean	hasTableLocationKey(@NotNull TableLocationKey tableLocationKey)	Check if this provider knows the supplied location key.
void	refresh()	Initialize or refresh state information about the list of existing locations.
void	subscribe(@NotNull 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(@NotNull 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 io.deephaven.engine.table.impl.locations.TableLocationProvider

getName, getTableLocation

Constructor Details

SingleTableLocationProvider

public SingleTableLocationProvider(@NotNull
 @NotNull TableLocation tableLocation)

Parameters:

tableLocation - The only table location that this provider will ever provide

Method Details

getImplementationName

public String getImplementationName()

Description copied from interface: NamedImplementation

Get a name for the implementing class. Useful for abstract classes that implement LogOutputAppendable or override toString.

The default implementation is correct, but not suitable for high-frequency usage.

Specified by:

getImplementationName in interface NamedImplementation

Returns:

A name for the implementing class

getKey

public ImmutableTableKey getKey()

Description copied from interface: TableLocationProvider

Get the TableKey associated with this provider.

Specified by:

getKey in interface TableLocationProvider

Returns:

The associated TableKey

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
 @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 handleTableLocationKey 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 run() after subscription completes.

Specified by:

subscribe in interface TableLocationProvider

Parameters:

listener - A listener.

unsubscribe

public void unsubscribe(@NotNull
 @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

getTableLocationKeys

@NotNull
public @NotNull Collection<ImmutableTableLocationKey> getTableLocationKeys()

Description copied from interface: TableLocationProvider

Get this provider's currently known location keys. The locations specified by the keys returned may have null size - that is, they may not "exist" for application purposes. TableLocationProvider.getTableLocation(TableLocationKey) is guaranteed to succeed for all results.

Specified by:

getTableLocationKeys in interface TableLocationProvider

Returns:

A collection of keys for locations available from this provider

hasTableLocationKey

public boolean hasTableLocationKey(@NotNull
 @NotNull TableLocationKey tableLocationKey)

Description copied from interface: TableLocationProvider

Check if this provider knows the supplied location key.

Specified by:

hasTableLocationKey in interface TableLocationProvider

Parameters:

tableLocationKey - The key to test for

Returns:

Whether the key is known to this provider

getTableLocationIfPresent

@Nullable
public @Nullable TableLocation getTableLocationIfPresent(@NotNull
 @NotNull TableLocationKey tableLocationKey)

Specified by:

getTableLocationIfPresent in interface TableLocationProvider

Parameters:

tableLocationKey - A TableLocationKey specifying the location to get

Returns:

The TableLocation matching the given key if present, else null