Module org.apache.jena.core

Package org.apache.jena.mem.store.indexed

Class EagerStoreStrategy

java.lang.Object

org.apache.jena.mem.store.indexed.EagerStoreStrategy

All Implemented Interfaces:

StoreStrategy

public class EagerStoreStrategy
extends Object
implements StoreStrategy

StoreStrategy that maintains a complete subject/predicate/object index over the triple set at all times.

Three node-keyed index maps (NodesToIndices) hold, for every subject/predicate/object node, an IndexList of the triple indices that mention it. Three parallel reverse-index arrays (sReverseIndices, pReverseIndices, oReverseIndices) store, for every triple slot, its position inside the corresponding IndexList; this is what makes O(1) removal possible.

A triple's reverse-index slot is only meaningful for the (s,p,o) component the triple actually has; readers must always validate via the indicesLarger[posLarger] == tripleIndex cross-check.

The reverse-index arrays are kept the same length as the underlying keys array of the TripleSet; whenever the triple set grows its keys array, the growReverseIndices hook is invoked to grow the reverse arrays too.

Constructor Summary

Constructors

Constructor	Description
EagerStoreStrategy(TripleSet triples)	Build a new eager strategy and index the triple set sequentially.
EagerStoreStrategy(TripleSet triples, boolean parallel)	Build a new eager strategy over the given triple set, indexing every triple already present.
EagerStoreStrategy(TripleSet triples, EagerStoreStrategy strategyToCopyIndicesFrom)	Copy constructor that reuses an already-built index.

Method Summary

Modifier and Type	Method	Description
void	addToIndex(Triple triple, int index)	Notify the strategy that a triple was added to the underlying triple set at the given index.
void	clearIndex()	Discard any auxiliary index data held by the strategy.
boolean	containsAnyAnyObj(Node o)
boolean	containsAnyPreAny(Node p)
boolean	containsAnyPreObj(Node p, Node o)
boolean	containsSubAnyAny(Node s)
boolean	containsSubAnyObj(Node s, Node o)
boolean	containsSubPreAny(Node s, Node p)
ExtendedIterator<Triple>	findAnyAnyObj(Node o)
ExtendedIterator<Triple>	findAnyPreAny(Node p)
ExtendedIterator<Triple>	findAnyPreObj(Node p, Node o)
ExtendedIterator<Triple>	findSubAnyAny(Node s)
ExtendedIterator<Triple>	findSubAnyObj(Node s, Node o)
ExtendedIterator<Triple>	findSubPreAny(Node s, Node p)
boolean	isIndexInitialized()	Check if the index has been initialized and all triples are indexed.
void	removeFromIndex(Triple triple, int index)	Notify the strategy that the triple at the given index has been removed from the underlying triple set.
Stream<Triple>	streamAnyAnyObj(Node o)
Stream<Triple>	streamAnyPreAny(Node p)
Stream<Triple>	streamAnyPreObj(Node p, Node o)
Stream<Triple>	streamSubAnyAny(Node s)
Stream<Triple>	streamSubAnyObj(Node s, Node o)
Stream<Triple>	streamSubPreAny(Node s, Node p)

Methods inherited from class java.lang.Object

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

Constructor Details

EagerStoreStrategy

public EagerStoreStrategy(TripleSet triples,
 boolean parallel)

Build a new eager strategy over the given triple set, indexing every triple already present.

Parameters:

triples - the canonical triple set

parallel - if true, build the three indices concurrently; otherwise build them sequentially

EagerStoreStrategy

public EagerStoreStrategy(TripleSet triples)

Build a new eager strategy and index the triple set sequentially. Equivalent to EagerStoreStrategy(triples, false).

Parameters:

triples - the canonical triple set

EagerStoreStrategy

public EagerStoreStrategy(TripleSet triples,
 EagerStoreStrategy strategyToCopyIndicesFrom)

Copy constructor that reuses an already-built index. Used when copying an IndexedSetTripleStore whose source already has its eager index built, so that the copy can avoid the cost of rebuilding it.

The triples parameter must be a copy of the original triple set (the indices reference triple slots by index, so the two sets must have identical layouts).

Parameters:

triples - the (already-copied) triple set the new strategy will operate on

strategyToCopyIndicesFrom - the strategy whose indices should be cloned

Method Details

isIndexInitialized

public boolean isIndexInitialized()

Description copied from interface: StoreStrategy

Check if the index has been initialized and all triples are indexed.

Specified by:

isIndexInitialized in interface StoreStrategy

Returns:

true if the index is initialized, false otherwise

addToIndex

public void addToIndex(Triple triple,
 int index)

Description copied from interface: StoreStrategy

Notify the strategy that a triple was added to the underlying triple set at the given index. Implementations that maintain an index must update it; implementations without an index are free to no-op.

Specified by:

addToIndex in interface StoreStrategy

Parameters:

triple - the newly added triple

index - the stable index it now occupies in the triple set

removeFromIndex

public void removeFromIndex(Triple triple,
 int index)

Description copied from interface: StoreStrategy

Notify the strategy that the triple at the given index has been removed from the underlying triple set. Implementations that maintain an index must remove the triple from it; implementations without an index are free to no-op.

Specified by:

removeFromIndex in interface StoreStrategy

Parameters:

triple - the removed triple

index - the index it occupied immediately before removal

clearIndex

public void clearIndex()

Description copied from interface: StoreStrategy

Discard any auxiliary index data held by the strategy. Implementations without an index may no-op.

Specified by:

clearIndex in interface StoreStrategy

containsSubAnyAny

public boolean containsSubAnyAny(Node s)

Specified by:

containsSubAnyAny in interface StoreStrategy

containsAnyPreAny

public boolean containsAnyPreAny(Node p)

Specified by:

containsAnyPreAny in interface StoreStrategy

containsAnyAnyObj

public boolean containsAnyAnyObj(Node o)

Specified by:

containsAnyAnyObj in interface StoreStrategy

containsSubPreAny

public boolean containsSubPreAny(Node s,
 Node p)

Specified by:

containsSubPreAny in interface StoreStrategy

containsSubAnyObj

public boolean containsSubAnyObj(Node s,
 Node o)

Specified by:

containsSubAnyObj in interface StoreStrategy

containsAnyPreObj

public boolean containsAnyPreObj(Node p,
 Node o)

Specified by:

containsAnyPreObj in interface StoreStrategy

streamSubAnyAny

public Stream<Triple> streamSubAnyAny(Node s)

Specified by:

streamSubAnyAny in interface StoreStrategy

streamAnyPreAny

public Stream<Triple> streamAnyPreAny(Node p)

Specified by:

streamAnyPreAny in interface StoreStrategy

streamAnyAnyObj

public Stream<Triple> streamAnyAnyObj(Node o)

Specified by:

streamAnyAnyObj in interface StoreStrategy

streamSubPreAny

public Stream<Triple> streamSubPreAny(Node s,
 Node p)

Specified by:

streamSubPreAny in interface StoreStrategy

streamSubAnyObj

public Stream<Triple> streamSubAnyObj(Node s,
 Node o)

Specified by:

streamSubAnyObj in interface StoreStrategy

streamAnyPreObj

public Stream<Triple> streamAnyPreObj(Node p,
 Node o)

Specified by:

streamAnyPreObj in interface StoreStrategy

findSubAnyAny

public ExtendedIterator<Triple> findSubAnyAny(Node s)

Specified by:

findSubAnyAny in interface StoreStrategy

findAnyPreAny

public ExtendedIterator<Triple> findAnyPreAny(Node p)

Specified by:

findAnyPreAny in interface StoreStrategy

findAnyAnyObj

public ExtendedIterator<Triple> findAnyAnyObj(Node o)

Specified by:

findAnyAnyObj in interface StoreStrategy

findSubPreAny

public ExtendedIterator<Triple> findSubPreAny(Node s,
 Node p)

Specified by:

findSubPreAny in interface StoreStrategy

findSubAnyObj

public ExtendedIterator<Triple> findSubAnyObj(Node s,
 Node o)

Specified by:

findSubAnyObj in interface StoreStrategy

findAnyPreObj

public ExtendedIterator<Triple> findAnyPreObj(Node p,
 Node o)

Specified by:

findAnyPreObj in interface StoreStrategy