Class MemStatementList

java.lang.Object

org.eclipse.rdf4j.sail.memory.model.MemStatementList

public class MemStatementList
extends Object

A dedicated data structure for storing MemStatement objects, offering operations optimized for their use in the memory Sail.

Field Summary

Fields

Modifier and Type	Field	Description
private static final MemStatement[]	EMPTY_ARRAY
private static final VarHandle	GUARANTEED_LAST_INDEX_IN_USE
private int	guaranteedLastIndexInUse
private static final VarHandle	PREVIOUSLY_INSERTED_INDEX
private int	previouslyInsertedIndex
private static final VarHandle	PRIORITISE_CLEANUP
private boolean	prioritiseCleanup
private final AtomicReference<Thread>	prioritisedThread
private int	size
private static final VarHandle	SIZE
private MemStatement[]	statements
private static final VarHandle	STATEMENTS
(package private) static final VarHandle	STATEMENTS_ARRAY

Constructor Summary

Constructors

Constructor	Description
MemStatementList()
MemStatementList(int capacity)

Method Summary

Modifier and Type	Method	Description
void	add(MemStatement st)
void	cleanSnapshots(int currentSnapshot)
void	clear()
MemStatement	getExact(MemResource subject, MemIRI predicate, MemValue object, MemResource context, int snapshot)	Iterates through this list and returns the statement that exactly matches the provided arguments.
int	getGuaranteedLastIndexInUse()
(package private) int	getRealSizeForTesting()
MemStatement[]	getStatements()	An internal method to retrieve the inner array that stores the statements.
private MemStatement[]	getStatementsWithoutInterrupt()
boolean	isEmpty()
private boolean	optimisticInnerRemove(MemStatement toRemove, MemStatement[] statements, int i)
boolean	optimisticRemove(MemStatement st)
boolean	optimisticRemove(MemStatement st, int index)
void	setPrioritiseCleanup(boolean prioritiseCleanup)
int	size()
private void	updateGuaranteedLastIndexInUse(int newValue)
(package private) boolean	verifySizeForTesting()

Methods inherited from class Object

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

Field Details

EMPTY_ARRAY

private static final MemStatement[] EMPTY_ARRAY

statements

private volatile MemStatement[] statements

STATEMENTS

private static final VarHandle STATEMENTS

STATEMENTS_ARRAY

static final VarHandle STATEMENTS_ARRAY

size

private volatile int size

SIZE

private static final VarHandle SIZE

previouslyInsertedIndex

private volatile int previouslyInsertedIndex

PREVIOUSLY_INSERTED_INDEX

private static final VarHandle PREVIOUSLY_INSERTED_INDEX

guaranteedLastIndexInUse

private volatile int guaranteedLastIndexInUse

GUARANTEED_LAST_INDEX_IN_USE

private static final VarHandle GUARANTEED_LAST_INDEX_IN_USE

prioritiseCleanup

private volatile boolean prioritiseCleanup

PRIORITISE_CLEANUP

private static final VarHandle PRIORITISE_CLEANUP

prioritisedThread

private final AtomicReference<Thread> prioritisedThread

Constructor Details

MemStatementList

public MemStatementList()

MemStatementList

public MemStatementList(int capacity)

Method Details

size

public int size()

isEmpty

public boolean isEmpty()

add

public void add(MemStatement st)
         throws InterruptedException

Throws:

InterruptedException

updateGuaranteedLastIndexInUse

private void updateGuaranteedLastIndexInUse(int newValue)

optimisticRemove

public boolean optimisticRemove(MemStatement st)
                         throws InterruptedException

Throws:

InterruptedException

optimisticRemove

public boolean optimisticRemove(MemStatement st,
 int index)
                         throws InterruptedException

Throws:

InterruptedException

optimisticInnerRemove

private boolean optimisticInnerRemove(MemStatement toRemove,
 MemStatement[] statements,
 int i)

clear

public void clear()

cleanSnapshots

public void cleanSnapshots(int currentSnapshot)
                    throws InterruptedException

Throws:

InterruptedException

getExact

public MemStatement getExact(MemResource subject,
 MemIRI predicate,
 MemValue object,
 MemResource context,
 int snapshot)
                      throws InterruptedException

Iterates through this list and returns the statement that exactly matches the provided arguments. The subject, predicate and object should not be null. If the context is null it will match statements with null as their context.

Parameters:

subject -

predicate -

object -

context -

snapshot -

Returns:

Throws:

InterruptedException

getStatements

public MemStatement[] getStatements()
                             throws InterruptedException

An internal method to retrieve the inner array that stores the statements. Useful to reduce the number of volatile reads.

Returns:

the underlying array og MemStatements

Throws:

InterruptedException

getStatementsWithoutInterrupt

private MemStatement[] getStatementsWithoutInterrupt()

getGuaranteedLastIndexInUse

public int getGuaranteedLastIndexInUse()

setPrioritiseCleanup

public void setPrioritiseCleanup(boolean prioritiseCleanup)

verifySizeForTesting

boolean verifySizeForTesting()

getRealSizeForTesting

int getRealSizeForTesting()