org.openrdf.sail.helpers
Class SailBase

java.lang.Object
  org.openrdf.sail.helpers.SailBase

All Implemented Interfaces:

Sail

Direct Known Subclasses:

NotifyingSailBase, RdbmsStore

public abstract class SailBase
extends Object
implements Sail

SailBase is 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

protected long	connectionTimeOut Connection timeout on shutdown (in ms).
protected static long	DEFAULT_CONNECTION_TIMEOUT Default connection timeout on shutdown: 20,000 milliseconds.
protected ReentrantReadWriteLock	initializationLock Lock used to synchronize the initialization state of a sail.
protected Logger	logger

Constructor Summary

SailBase()

Method Summary

protected void	connectionClosed(SailConnection connection) Signals to the store that the supplied connection has been closed; called by SailConnectionBase.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.
void	initialize() Initializes the Sail.
protected void	initializeInternal() Do store-specific operations to initialize the store.
protected boolean	isInitialized() Checks whether the Sail has been initialized.
void	setDataDir(File dataDir) Sets the data directory for the Sail.
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.openrdf.sail.Sail

getValueFactory, isWritable

Field Detail

DEFAULT_CONNECTION_TIMEOUT

protected static final long DEFAULT_CONNECTION_TIMEOUT

Default connection timeout on shutdown: 20,000 milliseconds.

See Also:

Constant Field Values

logger

protected final Logger logger

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 Detail

SailBase

public SailBase()

Method Detail

debugEnabled

protected static boolean debugEnabled()

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 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.

initialize

public void initialize()
                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:

initialize 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 SailConnectionBase.close().

Parameters:

connection - The connection that has been closed.