Package com.caplin.motif.datasource

Class CachedAdapter

java.lang.Object

com.caplin.motif.datasource.CachedAdapter

Direct Known Subclasses:

FXConfigAdapter, FXOrderAdapter, FXPrecisionAdapter, FXRatesAdapter, FXTradeAdapter, MMCalendarAdapter, MMRatesAdapter, UserDetailsAdapter

public class CachedAdapter
extends Object

Provides a Single-Request, Single-Discard DataSource API for a DataProvider and simplifies the Publisher API. This class also handles multiple peer requests for the same subscription by maintaining a cache, which is useful for fail-over and redundancy scenarios.

Usage:

 CachedAdapter adapter = new CachedAdapter(dataSource);
 CachedPublisher publisher = adapter.createActivePublisher(new NamespacePrefix("/FX"), this, new FXSubjectParser());
 

Constructor Summary

Constructors

Constructor	Description
CachedAdapter(com.caplin.datasource.DataSource dataSource)	Constructs a CachedAdapter to wrap requests made to the specified dataSource.

Method Summary

Modifier and Type	Method	Description
void	clearCache()	Clears the cache of subscriptions and cached records.
<T extends SubjectInfo> CachedPublisher	createActivePublisher(com.caplin.datasource.namespace.Namespace namespace, CachedDataProvider<T> dataProvider, SubjectParser<T> parser)	Deprecated. Use createCachedPublisher(Namespace, CachedDataProvider, SubjectParser)
<T extends SubjectInfo> CachedPublisher	createActivePublisher(com.caplin.datasource.namespace.Namespace namespace, CachedDataProvider<T> dataProvider, SubjectParser<T> parser, boolean sendDiscardAfterError)	Deprecated. Use createCachedPublisher(Namespace, CachedDataProvider, SubjectParser, boolean)
<T extends SubjectInfo> CachedPublisher	createCachedPublisher(com.caplin.datasource.namespace.Namespace namespace, CachedDataProvider<T> dataProvider, SubjectParser<T> parser)	Creates an CachedPublisher that will publish messages on the specified Namespace.
<T extends SubjectInfo> CachedPublisher	createCachedPublisher(com.caplin.datasource.namespace.Namespace namespace, CachedDataProvider<T> dataProvider, SubjectParser<T> parser, boolean sendDiscardAfterError)	Creates an ActivePublisher that will publish messages on the specified Namespace.
<T extends SubjectInfo> CachedPublisher	createCachedPublisher(String metricNamePrefix, com.caplin.datasource.namespace.Namespace namespace, CachedDataProvider<T> dataProvider, SubjectParser<T> parser)	Creates an CachedPublisher that will publish messages on the specified Namespace.
<T extends SubjectInfo> CachedPublisher	createCachedPublisher(String name, com.caplin.datasource.namespace.Namespace namespace, CachedDataProvider<T> dataProvider, SubjectParser<T> parser, boolean sendDiscardAfterError)	Creates an ActivePublisher that will publish messages on the specified Namespace.

Methods inherited from class java.lang.Object

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

Constructor Detail

CachedAdapter

public CachedAdapter(com.caplin.datasource.DataSource dataSource)

Constructs a CachedAdapter to wrap requests made to the specified dataSource.

Parameters:

dataSource - The dataSource to wrap.

Method Detail

createActivePublisher

@Deprecated
public <T extends SubjectInfo> CachedPublisher createActivePublisher(com.caplin.datasource.namespace.Namespace namespace,
                                                                     CachedDataProvider<T> dataProvider,
                                                                     SubjectParser<T> parser)

Deprecated.

Use createCachedPublisher(Namespace, CachedDataProvider, SubjectParser)

Creates an CachedPublisher that will publish messages on the specified Namespace.

This method uses a subject parser which allows subjects to be parsed into meaningful request objects.

Type Parameters:

T - The generic type erasure to provide compile time type-safety

Parameters:

namespace - The namespace that the publisher will publish on.

dataProvider - The provider that will accept requests and discards.

parser - The parser that will parse subject requests into a object representation of the request.

Returns:

The CachedPublisher to use for publishing messages.

createActivePublisher

@Deprecated
public <T extends SubjectInfo> CachedPublisher createActivePublisher(com.caplin.datasource.namespace.Namespace namespace,
                                                                     CachedDataProvider<T> dataProvider,
                                                                     SubjectParser<T> parser,
                                                                     boolean sendDiscardAfterError)

Deprecated.

Use createCachedPublisher(Namespace, CachedDataProvider, SubjectParser, boolean)

Creates an CachedPublisher that will publish messages on the specified Namespace.

This method uses a subject parser which allows subjects to be parsed into meaningful request objects

Type Parameters:

T - The generic type erasure to provide compile time type-safety

Parameters:

namespace - The namespace that the publisher will publish on.

dataProvider - The provider that will accept requests and discards.

parser - The parser that will parse subject requests into a object representation of the request.

sendDiscardAfterError - If set to TRUE, your DataProvider will receive an immediate callback on the CachedDataProvider.onDiscard(SubjectInfo) method after you publish a failure message by calling CachedPublisher.sendNotFound(String) or CachedPublisher.sendUnavailable(String). This can be useful if you want to use the same code path to clear a cache (for example) whether a subscription is ended by the client discarding it or the back end you are integrating with no longer providing the data.

Returns:

The CachedPublisher to use for publishing messages.

createCachedPublisher

public <T extends SubjectInfo> CachedPublisher createCachedPublisher(com.caplin.datasource.namespace.Namespace namespace,
                                                                     CachedDataProvider<T> dataProvider,
                                                                     SubjectParser<T> parser)

Creates an CachedPublisher that will publish messages on the specified Namespace.

This method uses a subject parser which allows subjects to be parsed into meaningful request objects.

Type Parameters:

T - The generic type erasure to provide compile time type-safety

Parameters:

namespace - The namespace that the publisher will publish on.

dataProvider - The provider that will accept requests and discards.

parser - The parser that will parse subject requests into a object representation of the request.

Returns:

The CachedPublisher to use for publishing messages.

createCachedPublisher

public <T extends SubjectInfo> CachedPublisher createCachedPublisher(String metricNamePrefix,
                                                                     com.caplin.datasource.namespace.Namespace namespace,
                                                                     CachedDataProvider<T> dataProvider,
                                                                     SubjectParser<T> parser)

Creates an CachedPublisher that will publish messages on the specified Namespace.

This method uses a subject parser which allows subjects to be parsed into meaningful request objects.

Type Parameters:

T - The generic type erasure to provide compile time type-safety

Parameters:

namespace - The namespace that the publisher will publish on.

dataProvider - The provider that will accept requests and discards.

parser - The parser that will parse subject requests into a object representation of the request.

metricNamePrefix - The prefix of the metric name

Returns:

The CachedPublisher to use for publishing messages.

createCachedPublisher

public <T extends SubjectInfo> CachedPublisher createCachedPublisher(com.caplin.datasource.namespace.Namespace namespace,
                                                                     CachedDataProvider<T> dataProvider,
                                                                     SubjectParser<T> parser,
                                                                     boolean sendDiscardAfterError)

Creates an ActivePublisher that will publish messages on the specified Namespace.

This method uses a subject parser which allows subjects to be parsed into meaningful request objects

Type Parameters:

T - The generic type erasure to provide compile time type-safety

Parameters:

namespace - The namespace that the publisher will publish on.

dataProvider - The provider that will accept requests and discards.

parser - The parser that will parse subject requests into a object representation of the request.

sendDiscardAfterError - If set to TRUE, your DataProvider will receive an immediate callback on the CachedDataProvider.onDiscard(SubjectInfo) method after you publish a failure message by calling CachedPublisher.sendNotFound(String) or CachedPublisher.sendUnavailable(String). This can be useful if you want to use the same code path to clear a cache (for example) whether a subscription is ended by the client discarding it or the back end you are integrating with no longer providing the data.

Returns:

The CachedPublisher to use for publishing messages.

createCachedPublisher

public <T extends SubjectInfo> CachedPublisher createCachedPublisher(String name,
                                                                     com.caplin.datasource.namespace.Namespace namespace,
                                                                     CachedDataProvider<T> dataProvider,
                                                                     SubjectParser<T> parser,
                                                                     boolean sendDiscardAfterError)

Creates an ActivePublisher that will publish messages on the specified Namespace.

This method uses a subject parser which allows subjects to be parsed into meaningful request objects

Type Parameters:

T - The generic type erasure to provide compile time type-safety

Parameters:

name - The prefix that will be used on publisher metrics.

namespace - The namespace that the publisher will publish on.

dataProvider - The provider that will accept requests and discards.

parser - The parser that will parse subject requests into a object representation of the request.

sendDiscardAfterError - If set to TRUE, your DataProvider will receive an immediate callback on the CachedDataProvider.onDiscard(SubjectInfo) method after you publish a failure message by calling CachedPublisher.sendNotFound(String) or CachedPublisher.sendUnavailable(String). This can be useful if you want to use the same code path to clear a cache (for example) whether a subscription is ended by the client discarding it or the back end you are integrating with no longer providing the data.

Returns:

The CachedPublisher to use for publishing messages.

clearCache

public void clearCache()

Clears the cache of subscriptions and cached records. Only invoke this method when a peer down message has been received.