org.apache.sling.distribution.journal.queue.impl

Class OffsetQueueImpl<T>

java.lang.Object

org.apache.sling.distribution.journal.queue.impl.OffsetQueueImpl<T>

All Implemented Interfaces:

OffsetQueueImplMBean, OffsetQueue<T>

@ParametersAreNonnullByDefault
public class OffsetQueueImpl<T>
extends Object
implements OffsetQueue<T>, OffsetQueueImplMBean

Constructor Summary

Constructors

Constructor and Description
OffsetQueueImpl()

Method Summary

Modifier and Type	Method and Description
T	getHeadItem() Return the item with the smallest offset in the queue.
Iterable<T>	getHeadItems(int skip, int limit) Return #limit items after skipping #skip items from the queue.
long	getHeadOffset()
T	getItem(long offset) Return the item at the given #offset.
OffsetQueue<T>	getMinOffsetQueue(long minOffset) Return an OffsetQueue offset queue which contains all the items from the current queue at an offset greater or equal to #minOffset.
int	getSize()
long	getTailOffset()
boolean	isEmpty()
void	putItem(long offset, T item) Put an item in the queue at the given offset.
void	putItems(OffsetQueue<T> offsetQueue) Put all the items from the #offsetQueue in this queue.

Methods inherited from class java.lang.Object

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

Constructor Detail

OffsetQueueImpl

public OffsetQueueImpl()

Method Detail

putItem

public void putItem(long offset,
                    T item)

Description copied from interface: OffsetQueue

Put an item in the queue at the given offset.

Specified by:

putItem in interface OffsetQueue<T>

Parameters:

offset - the offset associated to the item

item - the item to be stored at the given offset

putItems

public void putItems(OffsetQueue<T> offsetQueue)

Description copied from interface: OffsetQueue

Put all the items from the #offsetQueue in this queue.

Specified by:

putItems in interface OffsetQueue<T>

Parameters:

offsetQueue - the queue to be merged into this queue

getItem

public T getItem(long offset)

Description copied from interface: OffsetQueue

Return the item at the given #offset.

Specified by:

getItem in interface OffsetQueue<T>

Parameters:

offset - the offset of the item to be returned

Returns:

the item ; or null if no item could be found at the given offset

getHeadItem

public T getHeadItem()

Description copied from interface: OffsetQueue

Return the item with the smallest offset in the queue.

Specified by:

getHeadItem in interface OffsetQueue<T>

Returns:

the first item in the queue ; or null if the queue is empty

getHeadItems

@Nonnull
public Iterable<T> getHeadItems(int skip,
                                         int limit)

Description copied from interface: OffsetQueue

Return #limit items after skipping #skip items from the queue.

Specified by:

getHeadItems in interface OffsetQueue<T>

Parameters:

skip - the number of items to skip

limit - the maximum number of items to return. -1 will return all items.

Returns:

an iterable containing the items

getHeadOffset

public long getHeadOffset()

Specified by:

getHeadOffset in interface OffsetQueueImplMBean

Specified by:

getHeadOffset in interface OffsetQueue<T>

Returns:

the smallest offset stored in the queue ; or -1 if the queue is empty.

getTailOffset

public long getTailOffset()

Specified by:

getTailOffset in interface OffsetQueueImplMBean

Specified by:

getTailOffset in interface OffsetQueue<T>

Returns:

the largest offset stored in the queue ; or -1 if the queue is empty.

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface OffsetQueue<T>

Returns:

true if the queue is empty ; false otherwise

getSize

public int getSize()

Specified by:

getSize in interface OffsetQueueImplMBean

Specified by:

getSize in interface OffsetQueue<T>

Returns:

the number of items in the queue

getMinOffsetQueue

@Nonnull
public OffsetQueue<T> getMinOffsetQueue(long minOffset)

Description copied from interface: OffsetQueue

Return an OffsetQueue offset queue which contains all the items from the current queue at an offset greater or equal to #minOffset.

Specified by:

getMinOffsetQueue in interface OffsetQueue<T>

Parameters:

minOffset - the minimal offset of the items in the returned offset queue

Returns:

the offset queue