Package org.apache.flink.runtime.state.heap

Class KeyGroupPartitionedPriorityQueue<T,PQ extends InternalPriorityQueue<T> & HeapPriorityQueueElement>

java.lang.Object

org.apache.flink.runtime.state.heap.KeyGroupPartitionedPriorityQueue<T,PQ>

Type Parameters:

T - the type of elements in the queue.

PQ - the type of sub-queue used for each key-group partition.

All Implemented Interfaces:

InternalPriorityQueue<T>, KeyGroupedInternalPriorityQueue<T>

public class KeyGroupPartitionedPriorityQueue<T,PQ extends InternalPriorityQueue<T> & HeapPriorityQueueElement>
extends Object
implements InternalPriorityQueue<T>, KeyGroupedInternalPriorityQueue<T>

This implementation of InternalPriorityQueue is internally partitioned into sub-queues per key-group and essentially works as a heap-of-heaps. Instances will have set semantics for elements if the sub-queues have set semantics.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	KeyGroupPartitionedPriorityQueue.PartitionQueueSetFactory<T,PQS extends InternalPriorityQueue<T> & HeapPriorityQueueElement>	Factory that produces the sub-queues that represent the partitions of a KeyGroupPartitionedPriorityQueue.

Constructor Summary

Constructors

Constructor	Description
KeyGroupPartitionedPriorityQueue(KeyExtractorFunction<T> keyExtractor, PriorityComparator<T> elementPriorityComparator, KeyGroupPartitionedPriorityQueue.PartitionQueueSetFactory<T,PQ> orderedCacheFactory, KeyGroupRange keyGroupRange, int totalKeyGroups)

Method Summary

Modifier and Type	Method	Description
boolean	add(T toAdd)	Adds the given element to the set, if it is not already contained.
void	addAll(Collection<? extends T> toAdd)	Adds all the given elements to the set.
Set<T>	getSubsetForKeyGroup(int keyGroupId)	Returns the subset of elements in the priority queue that belongs to the given key-group, within the operator's key-group range.
boolean	isEmpty()	Check if the set contains any elements.
CloseableIterator<T>	iterator()	Iterator over all elements, no order guaranteed.
T	peek()	Retrieves, but does not remove, the element (w.r.t. order) of this set, or returns null if this set is empty.
T	poll()	Retrieves and removes the first element (w.r.t. the order) of this set, or returns null if this set is empty.
boolean	remove(T toRemove)	Removes the given element from the set, if is contained in the set.
int	size()	Returns the number of elements in this set.

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyGroupPartitionedPriorityQueue

public KeyGroupPartitionedPriorityQueue(@Nonnull
                                        KeyExtractorFunction<T> keyExtractor,
                                        @Nonnull
                                        PriorityComparator<T> elementPriorityComparator,
                                        @Nonnull
                                        KeyGroupPartitionedPriorityQueue.PartitionQueueSetFactory<T,PQ> orderedCacheFactory,
                                        @Nonnull
                                        KeyGroupRange keyGroupRange,
                                        @Nonnegative
                                        int totalKeyGroups)

Method Detail

poll

@Nullable
public T poll()

Description copied from interface: InternalPriorityQueue

Retrieves and removes the first element (w.r.t. the order) of this set, or returns null if this set is empty.

NOTE: Correct key (i.e. the key of the polled element) must be set on KeyContext before calling this method.

Specified by:

poll in interface InternalPriorityQueue<T>

Returns:

the first element of this ordered set, or null if this set is empty.

peek

@Nullable
public T peek()

Description copied from interface: InternalPriorityQueue

Retrieves, but does not remove, the element (w.r.t. order) of this set, or returns null if this set is empty.

Specified by:

peek in interface InternalPriorityQueue<T>

Returns:

the first element (w.r.t. order) of this ordered set, or null if this set is empty.

add

public boolean add(@Nonnull
                   T toAdd)

Description copied from interface: InternalPriorityQueue

Adds the given element to the set, if it is not already contained.

Specified by:

add in interface InternalPriorityQueue<T>

Parameters:

toAdd - the element to add to the set.

Returns:

true if the operation changed the head element or if it is unclear if the head element changed. Only returns false if the head element was not changed by this operation.

remove

public boolean remove(@Nonnull
                      T toRemove)

Description copied from interface: InternalPriorityQueue

Removes the given element from the set, if is contained in the set.

NOTE: Correct key (i.e. the key of the polled element) must be set on KeyContext before calling this method.

Specified by:

remove in interface InternalPriorityQueue<T>

Parameters:

toRemove - the element to remove.

Returns:

true if the operation changed the head element or if it is unclear if the head element changed. Only returns false if the head element was not changed by this operation.

isEmpty

public boolean isEmpty()

Description copied from interface: InternalPriorityQueue

Check if the set contains any elements.

Specified by:

isEmpty in interface InternalPriorityQueue<T>

Returns:

true if the set is empty, i.e. no element is contained.

size

public int size()

Description copied from interface: InternalPriorityQueue

Returns the number of elements in this set.

Specified by:

size in interface InternalPriorityQueue<T>

Returns:

the number of elements in this set.

addAll

public void addAll(@Nullable
                   Collection<? extends T> toAdd)

Description copied from interface: InternalPriorityQueue

Adds all the given elements to the set.

Specified by:

addAll in interface InternalPriorityQueue<T>

iterator

@Nonnull
public CloseableIterator<T> iterator()

Description copied from interface: InternalPriorityQueue

Iterator over all elements, no order guaranteed. Iterator must be closed after usage.

Specified by:

iterator in interface InternalPriorityQueue<T>

getSubsetForKeyGroup

@Nonnull
public Set<T> getSubsetForKeyGroup(int keyGroupId)

Description copied from interface: KeyGroupedInternalPriorityQueue

Returns the subset of elements in the priority queue that belongs to the given key-group, within the operator's key-group range.

Specified by:

getSubsetForKeyGroup in interface KeyGroupedInternalPriorityQueue<T>