Package org.eclipse.rdf4j.sail.helpers

Class AbstractSail

java.lang.Object

org.eclipse.rdf4j.sail.helpers.AbstractSail

All Implemented Interfaces:

Sail

Direct Known Subclasses:

AbstractNotifyingSail, FedX, FedXConnection.SailBaseDefaultImpl

public abstract class AbstractSail
extends Object
implements Sail

An abstract Sail implementation that takes care of common sail tasks, including proper closing of active connections and a grace period for active connections during shutdown of the store.

Author:

Herko ter Horst, jeen, Arjohn Kampman

Field Summary

Fields

Modifier and Type	Field	Description
protected long	connectionTimeOut	Connection timeout on shutdown (in ms).
protected static final long	DEFAULT_CONNECTION_TIMEOUT	Default connection timeout on shutdown: 20,000 milliseconds.
protected static final long	DEFAULT_ITERATION_SYNC_THRESHOLD	default value for the Iteration item sync threshold
protected final ReentrantReadWriteLock	initializationLock	Lock used to synchronize the initialization state of a sail.

Constructor Summary

Constructors

Constructor	Description
AbstractSail()

Method Summary

Modifier and Type	Method	Description
protected void	addSupportedIsolationLevel(IsolationLevels level)	Appends the provided IsolationLevels to the SAIL's list of supported isolation levels.
protected void	connectionClosed(SailConnection connection)	Signals to the store that the supplied connection has been closed; called by AbstractSailConnection.close().
protected static boolean	debugEnabled()
SailConnection	getConnection()	Opens a connection on the Sail which can be used to query and update data.
protected abstract SailConnection	getConnectionInternal()	Returns a store-specific SailConnection object.
File	getDataDir()	Gets the Sail's data directory.
IsolationLevel	getDefaultIsolationLevel()	Retrieves the default IsolationLevel level on which transactions in this Sail operate.
QueryEvaluationMode	getDefaultQueryEvaluationMode()
long	getIterationCacheSyncThreshold()	Retrieves the currently configured threshold for syncing query evaluation iteration caches to disk.
List<IsolationLevel>	getSupportedIsolationLevels()	Retrieve the IsolationLevels supported by this SAIL, ordered by increasing complexity.
void	init()	Initializes the Sail.
protected void	initializeInternal()	Do store-specific operations to initialize the store.
protected boolean	isInitialized()	Checks whether the Sail has been initialized.
boolean	isTrackResultSize()	Returns the status of the result size tracking for the query plan.
protected void	removeSupportedIsolationLevel(IsolationLevel level)	Removes all occurrences of the provided IsolationLevels in the list of supported Isolation levels.
void	setConnectionTimeOut(long connectionTimeOut)	Set connection timeout on shutdown (in ms).
void	setDataDir(File dataDir)	Sets the data directory for the Sail.
void	setDefaultIsolationLevel(IsolationLevel defaultIsolationLevel)	Sets the default IsolationLevel on which transactions in this Sail operate.
void	setDefaultQueryEvaluationMode(QueryEvaluationMode defaultQueryEvaluationMode)
void	setIterationCacheSyncThreshold(long iterationCacheSyncThreshold)	Set the threshold for syncing query evaluation iteration caches to disk.
protected void	setSupportedIsolationLevels(List<IsolationLevel> supportedIsolationLevels)	Sets the list of supported IsolationLevelss for this SAIL.
protected void	setSupportedIsolationLevels(IsolationLevel... supportedIsolationLevels)	Sets the list of supported IsolationLevelss for this SAIL.
void	setTrackResultSize(boolean trackResultSize)	Enable or disable results size tracking for the query plan.
void	shutDown()	Shuts down the Sail, giving it the opportunity to synchronize any stale data.
protected abstract void	shutDownInternal()	Do store-specific operations to ensure proper shutdown of the store.
String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.rdf4j.sail.Sail

getCollectionFactory, getValueFactory, isWritable

Field Details

DEFAULT_CONNECTION_TIMEOUT

protected static final long DEFAULT_CONNECTION_TIMEOUT

Default connection timeout on shutdown: 20,000 milliseconds.

See Also:

• Constant Field Values

DEFAULT_ITERATION_SYNC_THRESHOLD

protected static final long DEFAULT_ITERATION_SYNC_THRESHOLD

default value for the Iteration item sync threshold

See Also:

• Constant Field Values

initializationLock

protected final ReentrantReadWriteLock initializationLock

Lock used to synchronize the initialization state of a sail.

• write lock: initialize(), shutDown()
• read lock: getConnection()

connectionTimeOut

protected volatile long connectionTimeOut

Connection timeout on shutdown (in ms). Defaults to DEFAULT_CONNECTION_TIMEOUT.

Constructor Details

AbstractSail

public AbstractSail()

Method Details

debugEnabled

protected static boolean debugEnabled()

setConnectionTimeOut

public void setConnectionTimeOut(long connectionTimeOut)

Set connection timeout on shutdown (in ms).

Parameters:

connectionTimeOut - timeout (in ms)

setDataDir

public void setDataDir(File dataDir)

Description copied from interface: Sail

Sets the data directory for the Sail. The Sail can use this directory for storage of data, parameters, etc. This directory must be set before the Sail is

invalid reference

initialized

.

Specified by:

setDataDir in interface Sail

getDataDir

public File getDataDir()

Description copied from interface: Sail

Gets the Sail's data directory.

Specified by:

getDataDir in interface Sail

See Also:

• Sail.setDataDir(File)

toString

public String toString()

Overrides:

toString in class Object

isInitialized

protected boolean isInitialized()

Checks whether the Sail has been initialized. Sails are initialized from initialization until shutdown.

Returns:

true if the Sail has been initialized, false otherwise.

init

public void init()
          throws SailException

Description copied from interface: Sail

Initializes the Sail. Care should be taken that required initialization parameters have been set before this method is called. Please consult the specific Sail implementation for information about the relevant parameters.

Specified by:

init in interface Sail

Throws:

SailException - If the Sail could not be initialized.

initializeInternal

protected void initializeInternal()
                           throws SailException

Do store-specific operations to initialize the store. The default implementation of this method does nothing.

Throws:

SailException

shutDown

public void shutDown()
              throws SailException

Description copied from interface: Sail

Shuts down the Sail, giving it the opportunity to synchronize any stale data. Care should be taken that all initialized Sails are being shut down before an application exits to avoid potential loss of data. Once shut down, a Sail can no longer be used until it is re-initialized.

Specified by:

shutDown in interface Sail

Throws:

SailException - If the Sail object encountered an error or unexpected situation internally.

shutDownInternal

protected abstract void shutDownInternal()
                                  throws SailException

Do store-specific operations to ensure proper shutdown of the store.

Throws:

SailException

getConnection

public SailConnection getConnection()
                             throws SailException

Description copied from interface: Sail

Opens a connection on the Sail which can be used to query and update data. Depending on how the implementation handles concurrent access, a call to this method might block when there is another open connection on this Sail.

Specified by:

getConnection in interface Sail

Throws:

SailException - If no transaction could be started, for example because the Sail is not writable.

getConnectionInternal

protected abstract SailConnection getConnectionInternal()
                                                 throws SailException

Returns a store-specific SailConnection object.

Returns:

A connection to the store.

Throws:

SailException

connectionClosed

protected void connectionClosed(SailConnection connection)

Signals to the store that the supplied connection has been closed; called by AbstractSailConnection.close().

Parameters:

connection - The connection that has been closed.

addSupportedIsolationLevel

protected void addSupportedIsolationLevel(IsolationLevels level)

Appends the provided IsolationLevels to the SAIL's list of supported isolation levels.

Parameters:

level - a supported IsolationLevel.

removeSupportedIsolationLevel

protected void removeSupportedIsolationLevel(IsolationLevel level)

Removes all occurrences of the provided IsolationLevels in the list of supported Isolation levels.

Parameters:

level - the isolation level to remove.

setSupportedIsolationLevels

protected void setSupportedIsolationLevels(List<IsolationLevel> supportedIsolationLevels)

Sets the list of supported IsolationLevelss for this SAIL. The list is expected to be ordered in increasing complexity.

Parameters:

supportedIsolationLevels - a list of supported isolation levels.

setSupportedIsolationLevels

protected void setSupportedIsolationLevels(IsolationLevel... supportedIsolationLevels)

Sets the list of supported IsolationLevelss for this SAIL. The list is expected to be ordered in increasing complexity.

Parameters:

supportedIsolationLevels - a list of supported isolation levels.

getSupportedIsolationLevels

public List<IsolationLevel> getSupportedIsolationLevels()

Description copied from interface: Sail

Retrieve the IsolationLevels supported by this SAIL, ordered by increasing complexity.

Specified by:

getSupportedIsolationLevels in interface Sail

Returns:

a non-empty List of supported Isolation Levels, in order of increasing complexity. Every SAIL supports at least one IsolationLevel.

getDefaultIsolationLevel

public IsolationLevel getDefaultIsolationLevel()

Description copied from interface: Sail

Retrieves the default IsolationLevel level on which transactions in this Sail operate.

Specified by:

getDefaultIsolationLevel in interface Sail

Returns:

the IsolationLevel that will be used with SailConnection.begin(), for SAIL connections returned by Sail.getConnection().

setDefaultIsolationLevel

public void setDefaultIsolationLevel(IsolationLevel defaultIsolationLevel)

Sets the default IsolationLevel on which transactions in this Sail operate.

Parameters:

defaultIsolationLevel - The defaultIsolationLevel to set.

getIterationCacheSyncThreshold

public long getIterationCacheSyncThreshold()

Retrieves the currently configured threshold for syncing query evaluation iteration caches to disk.

Returns:

Returns the iterationCacheSyncThreshold.

setIterationCacheSyncThreshold

public void setIterationCacheSyncThreshold(long iterationCacheSyncThreshold)

Set the threshold for syncing query evaluation iteration caches to disk.

Parameters:

iterationCacheSyncThreshold - The iterationCacheSyncThreshold to set.

isTrackResultSize

public boolean isTrackResultSize()

Returns the status of the result size tracking for the query plan. Useful to determine which parts of a query plan generated the most data.

Returns:

true if result size tracking is enabled.

setTrackResultSize

public void setTrackResultSize(boolean trackResultSize)

Enable or disable results size tracking for the query plan. Useful to determine which parts of a query plan generated the most data.

Parameters:

trackResultSize - true to enable tracking.

getDefaultQueryEvaluationMode

public QueryEvaluationMode getDefaultQueryEvaluationMode()

Returns:

the defaultQueryEvaluationMode

setDefaultQueryEvaluationMode

public void setDefaultQueryEvaluationMode(QueryEvaluationMode defaultQueryEvaluationMode)

Parameters:

defaultQueryEvaluationMode - the defaultQueryEvaluationMode to set