com.devexperts.qd

Class SubscriptionBuffer

java.lang.Object

com.devexperts.qd.SubscriptionBuffer

All Implemented Interfaces:

SubscriptionConsumer, SubscriptionIterator, SubscriptionProvider, SubscriptionVisitor

Deprecated.

Use RecordBuffer with a mode of SUBSCRIPTION or HISTORY_SUBSCRIPTION.

@Deprecated
public class SubscriptionBuffer
extends Object
implements SubscriptionConsumer, SubscriptionProvider, SubscriptionIterator, SubscriptionVisitor

The SubscriptionBuffer class is an universal buffer for subscription, able to receive and retrieve subscription via all appropriate interfaces and via random access. It uses cyclic buffers for efficient subscription storage.

NOTE: the SubscriptionBuffer is not thread-safe; it is designed to be used in a single-thread mode.

Field Summary

Fields

Modifier and Type	Field and Description
static SubscriptionBuffer	VOID Deprecated. Many cases in code that use to this object do not need it any more. Double-check first. If really needed, then use SubscriptionVisitor.VOID, SubscriptionIterator.VOID, SubscriptionConsumer.VOID, or SubscriptionListener.VOID.

Constructor Summary

Constructors

Constructor and Description
SubscriptionBuffer() Deprecated.

Method Summary

Modifier and Type	Method and Description
void	clear() Deprecated. Clears this subscription buffer.
protected static void	copy(Object src, Object dst, int head, int tail, int length) Deprecated. Copies cyclic array buffer from source to destination.
protected void	ensureCapacity(DataRecord record) Deprecated. Ensures that this buffer has capacity to visit and store specified record.
void	examineRecord(int index, SubscriptionVisitor visitor) Deprecated. Examines record by its index within this buffer via specivied visitor.
boolean	examineSubscription(SubscriptionVisitor visitor) Deprecated. Examines accumulated subscription via specified subscription visitor.
SubscriptionIterator	examiningIterator() Deprecated. Returns subscription iterator that examines this subscription buffer.
int	getCipher() Deprecated. Returns cipher for the current record returned by last call to SubscriptionIterator.nextRecord().
int	getCipher(int index) Deprecated. Returns cipher of the record by its index within this buffer.
DataRecord	getRecord(int index) Deprecated. Returns record by its index within this buffer.
String	getSymbol() Deprecated. Returns symbol for the current record returned by last call to SubscriptionIterator.nextRecord().
String	getSymbol(int index) Deprecated. Returns symbol of the record by its index within this buffer.
long	getTime() Deprecated. Returns time for the current record returned by last call to SubscriptionIterator.nextRecord().
long	getTime(int index) Deprecated. Returns time of the record by its index within this buffer.
boolean	hasCapacity() Deprecated. Returns whether visitor has capacity to efficiently visit next record.
boolean	isEmpty() Deprecated. Returns true if this subscription buffer has no records.
DataRecord	nextRecord() Deprecated. Returns next record.
protected void	notifyListener() Deprecated. Notifies subscription listener used in SubscriptionProvider part of this subscription buffer.
static boolean	process(SubscriptionIterator iterator, SubscriptionVisitor visitor) Deprecated. Use RecordBuffer.retrieveSubscription(SubscriptionVisitor) or LegacyIteratorUtils.processSubscription(SubscriptionIterator, SubscriptionVisitor) as last resort.
void	processSubscription(SubscriptionIterator iterator) Deprecated. Processes subscription from specified subscription iterator.
boolean	retrieveSubscription(SubscriptionVisitor visitor) Deprecated. Retrieves accumulated subscription into specified subscription visitor.
void	setSubscriptionListener(SubscriptionListener listener) Deprecated. Sets new subscription listener to receive notifications about subscription.
int	size() Deprecated. Returns number of records in this subscription buffer.
void	visitRecord(DataRecord record, int cipher, String symbol) Deprecated. Visits next record using time = 0.
void	visitRecord(DataRecord record, int cipher, String symbol, long time) Deprecated. Visits next record.

Methods inherited from class java.lang.Object

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

Field Detail

VOID

public static final SubscriptionBuffer VOID

Deprecated. Many cases in code that use to this object do not need it any more. Double-check first. If really needed, then use SubscriptionVisitor.VOID, SubscriptionIterator.VOID, SubscriptionConsumer.VOID, or SubscriptionListener.VOID.

The instance of SubscriptionBuffer that is always empty.

Constructor Detail

SubscriptionBuffer

public SubscriptionBuffer()

Deprecated.

Method Detail

process

public static boolean process(SubscriptionIterator iterator,
                              SubscriptionVisitor visitor)

Deprecated. Use RecordBuffer.retrieveSubscription(SubscriptionVisitor) or LegacyIteratorUtils.processSubscription(SubscriptionIterator, SubscriptionVisitor) as last resort.

Processes subscription from specified iterator via specified visitor. Returns true if some subscription may still remain in the iterator or false if all subscription were processed.

size

public int size()

Deprecated.

Returns number of records in this subscription buffer.

isEmpty

public boolean isEmpty()

Deprecated.

Returns true if this subscription buffer has no records.

clear

public void clear()

Deprecated.

Clears this subscription buffer.

getCipher

public int getCipher(int index)

Deprecated.

Returns cipher of the record by its index within this buffer. Returns 0 if not encoded.

Throws:

IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size()).

getSymbol

public String getSymbol(int index)

Deprecated.

Returns symbol of the record by its index within this buffer. Returns null if encoded.

Throws:

IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size()).

getTime

public long getTime(int index)

Deprecated.

Returns time of the record by its index within this buffer. Returns 0 if not historical.

Throws:

IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size()).

getRecord

public DataRecord getRecord(int index)

Deprecated.

Returns record by its index within this buffer.

Throws:

IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size()).

examineRecord

public void examineRecord(int index,
                          SubscriptionVisitor visitor)

Deprecated.

Examines record by its index within this buffer via specivied visitor.

NOTE: unlike bulk transfer methods, this method does not check SubscriptionVisitor.hasCapacity() method of specified visitor.

Throws:

IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size()).

examineSubscription

public boolean examineSubscription(SubscriptionVisitor visitor)

Deprecated.

Examines accumulated subscription via specified subscription visitor. Unlike retrieval, examination does not consume processed subscription. Returns true if not all accumulated subscription were examined or false if all accumulated subscription were examined.

examiningIterator

public SubscriptionIterator examiningIterator()

Deprecated.

Returns subscription iterator that examines this subscription buffer.

NOTE: returned iterator possesses no special protection against concurrent modifications of this buffer and it will fail in unexpected way in such event; it should be used up before any such modifications.

processSubscription

public void processSubscription(SubscriptionIterator iterator)

Deprecated.

Description copied from interface: SubscriptionConsumer

Processes subscription from specified subscription iterator.

Specified by:

processSubscription in interface SubscriptionConsumer

retrieveSubscription

public boolean retrieveSubscription(SubscriptionVisitor visitor)

Deprecated.

Description copied from interface: SubscriptionProvider

Retrieves accumulated subscription into specified subscription visitor. Returns true if some subscription still remains in the provider or false if all accumulated subscription were retrieved.

Specified by:

retrieveSubscription in interface SubscriptionProvider

setSubscriptionListener

public void setSubscriptionListener(SubscriptionListener listener)

Deprecated.

Description copied from interface: SubscriptionProvider

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

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

Specified by:

setSubscriptionListener in interface SubscriptionProvider

getCipher

public int getCipher()

Deprecated.

Description copied from interface: SubscriptionIterator

Returns cipher for the current record returned by last call to SubscriptionIterator.nextRecord(). Returns 0 if not encoded or if no current record is being iterated.

Specified by:

getCipher in interface SubscriptionIterator

getSymbol

public String getSymbol()

Deprecated.

Description copied from interface: SubscriptionIterator

Returns symbol for the current record returned by last call to SubscriptionIterator.nextRecord(). Returns null if encoded or if no current record is being iterated.

Specified by:

getSymbol in interface SubscriptionIterator

getTime

public long getTime()

Deprecated.

Description copied from interface: SubscriptionIterator

Returns time for the current record returned by last call to SubscriptionIterator.nextRecord(). Returns 0 if not historical or if no current record is being iterated.

Specified by:

getTime in interface SubscriptionIterator

nextRecord

public DataRecord nextRecord()

Deprecated.

Description copied from interface: SubscriptionIterator

Returns next record. Returns null if no more records available.

Specified by:

nextRecord in interface SubscriptionIterator

hasCapacity

public boolean hasCapacity()

Deprecated.

Description copied from interface: SubscriptionVisitor

Returns whether visitor has capacity to efficiently visit next record. This method may be used to advise subscription provider that it is desirable to stop current string of visiting and to keep remaining subscription. However, at present, subscription provider is not obliged to adhere to this method contract.

NOTE: subscription visitor must process all subscription that is passed to it via visitXXX calls no matter whether it has capacity to do it efficiently.

Specified by:

hasCapacity in interface SubscriptionVisitor

visitRecord

public void visitRecord(DataRecord record,
                        int cipher,
                        String symbol,
                        long time)

Deprecated.

Description copied from interface: SubscriptionVisitor

Visits next record.

Specified by:

visitRecord in interface SubscriptionVisitor

visitRecord

public void visitRecord(DataRecord record,
                        int cipher,
                        String symbol)

Deprecated.

Visits next record using time = 0.

notifyListener

protected void notifyListener()

Deprecated.

Notifies subscription listener used in SubscriptionProvider part of this subscription buffer. Does not check actual subscription availability.

ensureCapacity

protected void ensureCapacity(DataRecord record)

Deprecated.

Ensures that this buffer has capacity to visit and store specified record. If required, reallocates all internal buffers, copies data and rearranges heads and tails to start with 0.

copy

protected static void copy(Object src,
                           Object dst,
                           int head,
                           int tail,
                           int length)

Deprecated.

Copies cyclic array buffer from source to destination. Uses source, source head index, source tail index and source length. The destination buffer will start with 0 and end with original size.