org.openrdf.sail.federation

Class Federation

java.lang.Object

org.openrdf.sail.federation.Federation

All Implemented Interfaces:

Executor, HttpClientDependent, SesameClientDependent, FederatedServiceResolverClient, RepositoryResolverClient, Sail

public class Federation
extends Object
implements Sail, Executor, FederatedServiceResolverClient, RepositoryResolverClient, HttpClientDependent, SesameClientDependent

Union multiple (possibly remote) Repositories into a single RDF store.

Author:

James Leigh, Arjohn Kampman

Constructor Summary

Constructors

Constructor and Description
Federation()

Method Summary

Modifier and Type	Method and Description
void	addMember(Repository member)
protected EvaluationStrategy	createEvaluationStrategy(TripleSource tripleSource, Dataset dataset, FederatedServiceResolver resolver)
void	execute(Runnable command) Required by Executor interface.
SailConnection	getConnection() Opens a connection on the Sail which can be used to query and update data.
File	getDataDir() Gets the Sail's data directory.
IsolationLevel	getDefaultIsolationLevel() Retrieves the default IsolationLevel level on which transactions in this Sail operate.
FederatedServiceResolver	getFederatedServiceResolver()
org.apache.http.client.HttpClient	getHttpClient() HttpClient that has been assigned or has been used by this object.
PrefixHashSet	getLocalPropertySpace()
SesameClient	getSesameClient() SesameClient that has been assigned or has been used by this object.
List<IsolationLevel>	getSupportedIsolationLevels() Retrieve the IsolationLevels supported by this SAIL, ordered by increasing complexity.
ValueFactory	getValueFactory() Gets a ValueFactory object that can be used to create URI-, blank node-, literal- and statement objects.
void	initialize() Initializes the Sail.
boolean	isDistinct()
boolean	isReadOnly()
boolean	isWritable() Checks whether this Sail object is writable, i.e.
void	setDataDir(File dataDir) Sets the data directory for the Sail.
void	setDistinct(boolean distinct)
void	setFederatedServiceResolver(FederatedServiceResolver resolver) Overrides the FederatedServiceResolver used by this instance, but the given resolver is not shutDown when this instance is.
void	setHttpClient(org.apache.http.client.HttpClient client) Assign an HttpClient that this object should use.
void	setLocalPropertySpace(Collection<String> localPropertySpace)
void	setReadOnly(boolean readOnly)
void	setRepositoryResolver(RepositoryResolver resolver)
void	setSesameClient(SesameClient client) Assign an SesameClient that this object should use.
void	shutDown() Shuts down the Sail, giving it the opportunity to synchronize any stale data.

Methods inherited from class java.lang.Object

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

Constructor Detail

Federation

public Federation()

Method Detail

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)

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

getValueFactory

public ValueFactory getValueFactory()

Description copied from interface: Sail

Gets a ValueFactory object that can be used to create URI-, blank node-, literal- and statement objects.

Specified by:

getValueFactory in interface Sail

Returns:

a ValueFactory object for this Sail object.

isWritable

public boolean isWritable()
                   throws SailException

Description copied from interface: Sail

Checks whether this Sail object is writable, i.e. if the data contained in this Sail object can be changed.

Specified by:

isWritable in interface Sail

Throws:

SailException

addMember

public void addMember(Repository member)

getLocalPropertySpace

public PrefixHashSet getLocalPropertySpace()

Returns:

PrefixHashSet or null

setLocalPropertySpace

public void setLocalPropertySpace(Collection<String> localPropertySpace)

isDistinct

public boolean isDistinct()

setDistinct

public void setDistinct(boolean distinct)

isReadOnly

public boolean isReadOnly()

setReadOnly

public void setReadOnly(boolean readOnly)

getFederatedServiceResolver

public FederatedServiceResolver getFederatedServiceResolver()

Returns:

Returns the SERVICE resolver.

setFederatedServiceResolver

public void setFederatedServiceResolver(FederatedServiceResolver resolver)

Overrides the FederatedServiceResolver used by this instance, but the given resolver is not shutDown when this instance is.

Specified by:

setFederatedServiceResolver in interface FederatedServiceResolverClient

Parameters:

reslover - The SERVICE resolver to set.

setRepositoryResolver

public void setRepositoryResolver(RepositoryResolver resolver)

Specified by:

setRepositoryResolver in interface RepositoryResolverClient

getSesameClient

public SesameClient getSesameClient()

Description copied from interface: SesameClientDependent

SesameClient that has been assigned or has been used by this object. The life cycle might not be or might be tied to this object, depending on whether SesameClient was passed to or created by this object respectively.

Specified by:

getSesameClient in interface SesameClientDependent

Returns:

a SesameClient instance or null

setSesameClient

public void setSesameClient(SesameClient client)

Description copied from interface: SesameClientDependent

Assign an SesameClient that this object should use. The life cycle of the given SesameClient is independent of this object. Closing or shutting down this object does not have any impact on the given client. Callers must ensure that the given client is properly closed elsewhere.

Specified by:

setSesameClient in interface SesameClientDependent

getHttpClient

public org.apache.http.client.HttpClient getHttpClient()

Description copied from interface: HttpClientDependent

HttpClient that has been assigned or has been used by this object. The life cycle might not be or might be tied to this object, depending on whether HttpClient was passed to or created by this object respectively.

Specified by:

getHttpClient in interface HttpClientDependent

Returns:

an HttpClient instance or null

setHttpClient

public void setHttpClient(org.apache.http.client.HttpClient client)

Description copied from interface: HttpClientDependent

Assign an HttpClient that this object should use. The life cycle of the given HttpClient is independent of this object. Closing or shutting down this object does not have any impact on the given client. Callers must ensure that the given client is properly closed elsewhere.

Specified by:

setHttpClient in interface HttpClientDependent

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.

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.

execute

public void execute(Runnable command)

Required by Executor interface.

Specified by:

execute in interface Executor

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.

createEvaluationStrategy

protected EvaluationStrategy createEvaluationStrategy(TripleSource tripleSource,
                                                      Dataset dataset,
                                                      FederatedServiceResolver resolver)

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().