com.devexperts.qd.util

Class CompositeRecordProvider

java.lang.Object

com.devexperts.qd.ng.AbstractRecordProvider

com.devexperts.qd.util.CompositeRecordProvider

All Implemented Interfaces:

DataProvider, RecordProvider, SubscriptionProvider

public final class CompositeRecordProvider
extends AbstractRecordProvider

This class provides an efficient implementation of composite RecordProvider that listens for multiple RecordProvider instances and on retrieve method invocation only retrieves data from the providers that have data available. This class is thread-safe and lock-free. Change carefully.

Field Summary

Fields inherited from interface com.devexperts.qd.ng.RecordProvider

VOID

Constructor Summary

Constructors

Constructor and Description
CompositeRecordProvider(RecordProvider... providers) Constructs an instance of CompositeRecordProvider for a given list of individual providers.

Method Summary

Modifier and Type	Method and Description
RecordMode	getMode() Returns record mode at which the records are provided by retrieve method.
boolean	retrieve(RecordSink sink) Retrieves accumulated records into the specified record sink while the sink has capacity.
void	setRecordListener(RecordListener listener) Sets new record listener to receive notifications about available records.

Methods inherited from class com.devexperts.qd.ng.AbstractRecordProvider

retrieveData, retrieveSubscription, setDataListener, setSubscriptionListener

Methods inherited from class java.lang.Object

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

Constructor Detail

CompositeRecordProvider

public CompositeRecordProvider(RecordProvider... providers)

Constructs an instance of CompositeRecordProvider for a given list of individual providers.

Method Detail

getMode

public RecordMode getMode()

Description copied from class: AbstractRecordProvider

Returns record mode at which the records are provided by retrieve method.

Specified by:

getMode in interface RecordProvider

Specified by:

getMode in class AbstractRecordProvider

retrieve

public boolean retrieve(RecordSink sink)

Description copied from class: AbstractRecordProvider

Retrieves accumulated records into the specified record sink while the sink has capacity. Returns true if some records still remains in the provider or false if all accumulated records were retrieved.

Specified by:

retrieve in interface RecordProvider

Specified by:

retrieve in class AbstractRecordProvider

Parameters:

sink - the sink.

Returns:

true if some records still remains in the provider, false if all accumulated records were retrieved.

setRecordListener

public void setRecordListener(RecordListener listener)

Description copied from class: AbstractRecordProvider

Sets new record listener to receive notifications about available records. Only one listener at a time is supported; the former listener is discarded. Use null to set empty data listener (no notifications).

NOTE: if there are accumulated data available, then specified listener will be notified by this method.

This implementation throws UnsupportedOperationException.

Specified by:

setRecordListener in interface RecordProvider

Overrides:

setRecordListener in class AbstractRecordProvider

Parameters:

listener - the listener.