Package com.epam.fixengine.storage.queue

Class PersistentInMemoryQueue<T extends Queueable>

java.lang.Object

com.epam.fixengine.storage.queue.InMemoryQueue<T>

com.epam.fixengine.storage.queue.PersistentInMemoryQueue<T>

All Implemented Interfaces:

Queue<T>

public class PersistentInMemoryQueue<T extends Queueable>
extends InMemoryQueue<T>
implements Queue<T>

Persistent queue file format is the following: 1 byte record length length [n]; n bytes record length [m] m bytes record itself DELETE marker is byte == (byte)0;

See Also:

• Queueable

Field Summary

Fields

Modifier and Type	Field	Description
protected static final Queueable	DELETE_MARKER
protected boolean	isForcedFlush

Fields inherited from class com.epam.fixengine.storage.queue.InMemoryQueue

application, maskedTags, session

Constructor Summary

Constructors

Constructor	Description
PersistentInMemoryQueue(String filename, QueueableFactory<T> factory)	Deprecated.
PersistentInMemoryQueue(String filename, QueueableFactory<T> factory, com.epam.fixengine.configuration.Configuration conf)

Method Summary

Modifier and Type	Method	Description
boolean	add(T element)	Add object to the queue.
protected boolean	appendEntryToFile(Queueable entry)	Appends entry to file.
void	clear()	Clears the queue.
void	commit()	Removes polled object from the queue.
void	initialize()	Initializes queue.
void	shutdown()	Gracefully shutdowns queue.

Methods inherited from class com.epam.fixengine.storage.queue.InMemoryQueue

addOutOfTurn, clearOutOfTurn, isAllEmpty, isApplicationCommit, isEmpty, isOutOfTurnOnlyMode, isShutdown, notifyAllApplication, notifyAllSession, poll, setOutOfTurnOnlyMode, size, toArray, totalSize

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.epam.fixengine.storage.queue.Queue

addOutOfTurn, clearOutOfTurn, isAllEmpty, isEmpty, isOutOfTurnOnlyMode, notifyAllApplication, notifyAllSession, poll, setOutOfTurnOnlyMode, size, toArray, totalSize

Field Details

DELETE_MARKER

protected static final Queueable DELETE_MARKER

isForcedFlush

protected boolean isForcedFlush

Constructor Details

PersistentInMemoryQueue

@Deprecated
public PersistentInMemoryQueue(String filename,
 QueueableFactory<T> factory)

Deprecated.

PersistentInMemoryQueue

public PersistentInMemoryQueue(String filename,
 QueueableFactory<T> factory,
 com.epam.fixengine.configuration.Configuration conf)

Method Details

initialize

public void initialize()

Description copied from interface: Queue

Initializes queue. That includes restore of previously saved queue content for persistent queues.

Specified by:

initialize in interface Queue<T extends Queueable>

Overrides:

initialize in class InMemoryQueue<T extends Queueable>

See Also:

• Queue.initialize()

commit

public void commit()

Description copied from interface: Queue

Removes polled object from the queue. If nothing was polled - throws IllegalStateException

Specified by:

commit in interface Queue<T extends Queueable>

Overrides:

commit in class InMemoryQueue<T extends Queueable>

See Also:

• Queue.commit()

clear

public void clear()

Description copied from interface: Queue

Clears the queue.

Specified by:

clear in interface Queue<T extends Queueable>

Overrides:

clear in class InMemoryQueue<T extends Queueable>

See Also:

• Queue.clear()

add

public boolean add(T element)

Description copied from interface: Queue

Add object to the queue.

Specified by:

add in interface Queue<T extends Queueable>

Overrides:

add in class InMemoryQueue<T extends Queueable>

Parameters:

element - the element

Returns:

true if element added successfully.

See Also:

• Queue.add(Queueable)

appendEntryToFile

protected boolean appendEntryToFile(Queueable entry)

Appends entry to file.

Methods append entry to file if it is opened. Method truncates the file only if entry is DELETE_MARKER and size of file gr ONE_MEG .

Returns:

false if entry doesn't append to file.

shutdown

public void shutdown()

Description copied from interface: Queue

Gracefully shutdowns queue.

Specified by:

shutdown in interface Queue<T extends Queueable>

Overrides:

shutdown in class InMemoryQueue<T extends Queueable>

See Also:

• Queue.shutdown()