org.openrdf.sail
Interface SailConnection

All Known Subinterfaces:

InferencerConnection, NotifyingSailConnection

All Known Implementing Classes:

InferencerConnectionWrapper, MemoryStoreConnection, NativeStoreConnection, NotifyingSailConnectionBase, NotifyingSailConnectionWrapper, RdbmsConnection, SailConnectionBase, SailConnectionWrapper

public interface SailConnection

A connection to an RDF Sail object. A SailConnection is active from the moment it is created until it is closed. Care should be taken to properly close SailConnections as they might block concurrent queries and/or updates on the Sail while active, depending on the Sail-implementation that is being used.

Author:

jeen, Arjohn Kampman

Method Summary

void	addStatement(Resource subj, URI pred, Value obj, Resource... contexts) Adds a statement to the store.
void	clear(Resource... contexts) Removes all statements from the specified/all contexts.
void	clearNamespaces() Removes all namespace declarations from the repository.
void	close() Closes the connection.
void	commit() Commits any updates that have been performed since the last time commit() or rollback() was called.
CloseableIteration<? extends BindingSet,QueryEvaluationException>	evaluate(TupleExpr tupleExpr, Dataset dataset, BindingSet bindings, boolean includeInferred) Evaluates the supplied TupleExpr on the data contained in this Sail object, using the (optional) dataset and supplied bindings as input parameters.
CloseableIteration<? extends Resource,SailException>	getContextIDs() Returns the set of all unique context identifiers that are used to store statements.
String	getNamespace(String prefix) Gets the namespace that is mapped to the specified prefix.
CloseableIteration<? extends Namespace,SailException>	getNamespaces() Gets the namespaces relevant to the data contained in this Sail object.
CloseableIteration<? extends Statement,SailException>	getStatements(Resource subj, URI pred, Value obj, boolean includeInferred, Resource... contexts) Gets all statements from the specified contexts that have a specific subject, predicate and/or object.
boolean	isOpen() Checks whether this SailConnection is open.
void	removeNamespace(String prefix) Removes a namespace declaration by removing the association between a prefix and a namespace name.
void	removeStatements(Resource subj, URI pred, Value obj, Resource... contexts) Removes all statements matching the specified subject, predicate and object from the repository.
void	rollback() Rolls back the SailConnection, discarding any uncommitted changes that have been made in this SailConnection.
void	setNamespace(String prefix, String name) Sets the prefix of a namespace.
long	size(Resource... contexts) Returns the number of (explicit) statements in the store, or in specific contexts.

Method Detail

isOpen

boolean isOpen()
               throws SailException

Checks whether this SailConnection is open. A SailConnection is open from the moment it is created until it is closed.

Throws:

SailException

See Also:

close()

close

void close()
           throws SailException

Closes the connection. Any updates that haven't been committed yet will be rolled back. The connection can no longer be used once it is closed.

Throws:

SailException

evaluate

CloseableIteration<? extends BindingSet,QueryEvaluationException> evaluate(TupleExpr tupleExpr,
                                                                           Dataset dataset,
                                                                           BindingSet bindings,
                                                                           boolean includeInferred)
                                                                           throws SailException

Evaluates the supplied TupleExpr on the data contained in this Sail object, using the (optional) dataset and supplied bindings as input parameters.

Parameters:

tupleExpr - The tuple expression to evaluate.

dataset - The dataset to use for evaluating the query, null to use the Sail's default dataset.

bindings - A set of input parameters for the query evaluation. The keys reference variable names that should be bound to the value they map to.

includeInferred - Indicates whether inferred triples are to be considered in the query result. If false, no inferred statements are returned; if true, inferred statements are returned if available

Returns:

The TupleQueryResult.

Throws:

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

IllegalStateException - If the connection has been closed.

getContextIDs

CloseableIteration<? extends Resource,SailException> getContextIDs()
                                                                   throws SailException

Returns the set of all unique context identifiers that are used to store statements.

Returns:

An iterator over the context identifiers, should not contain any duplicates.

Throws:

IllegalStateException - If the connection has been closed.

SailException

getStatements

CloseableIteration<? extends Statement,SailException> getStatements(Resource subj,
                                                                    URI pred,
                                                                    Value obj,
                                                                    boolean includeInferred,
                                                                    Resource... contexts)
                                                                    throws SailException

Gets all statements from the specified contexts that have a specific subject, predicate and/or object. All three parameters may be null to indicate wildcards. The includeInferred parameter can be used to control which statements are fetched: all statements or only the statements that have been added explicitly.

Parameters:

subj - A Resource specifying the subject, or null for a wildcard.

pred - A URI specifying the predicate, or null for a wildcard.

obj - A Value specifying the object, or null for a wildcard.

includeInferred - if false, no inferred statements are returned; if true, inferred statements are returned if available

contexts - The context(s) to get the data from. Note that this parameter is a vararg and as such is optional. If no contexts are specified the method operates on the entire repository. A null value can be used to match context-less statements.

Returns:

The statements matching the specified pattern.

Throws:

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

IllegalStateException - If the connection has been closed.

size

long size(Resource... contexts)
          throws SailException

Returns the number of (explicit) statements in the store, or in specific contexts.

Parameters:

contexts - The context(s) to determine the size of. Note that this parameter is a vararg and as such is optional. If no contexts are specified the method operates on the entire repository. A null value can be used to match context-less statements.

Returns:

The number of explicit statements in this store, or in the specified context(s).

Throws:

IllegalStateException - If the connection has been closed.

SailException

commit

void commit()
            throws SailException

Commits any updates that have been performed since the last time commit() or rollback() was called.

Throws:

SailException - If the SailConnection could not be committed.

IllegalStateException - If the connection has been closed.

rollback

void rollback()
              throws SailException

Rolls back the SailConnection, discarding any uncommitted changes that have been made in this SailConnection.

Throws:

SailException - If the SailConnection could not be rolled back.

IllegalStateException - If the connection has been closed.

addStatement

void addStatement(Resource subj,
                  URI pred,
                  Value obj,
                  Resource... contexts)
                  throws SailException

Adds a statement to the store.

Parameters:

subj - The subject of the statement to add.

pred - The predicate of the statement to add.

obj - The object of the statement to add.

contexts - The context(s) to add the statement to. Note that this parameter is a vararg and as such is optional. If no contexts are specified, a context-less statement will be added.

Throws:

SailException - If the statement could not be added.

IllegalStateException - If the connection has been closed.

removeStatements

void removeStatements(Resource subj,
                      URI pred,
                      Value obj,
                      Resource... contexts)
                      throws SailException

Removes all statements matching the specified subject, predicate and object from the repository. All three parameters may be null to indicate wildcards.

Parameters:

subj - The subject of the statement that should be removed, or null to indicate a wildcard.

pred - The predicate of the statement that should be removed, or null to indicate a wildcard.

obj - The object of the statement that should be removed , or null to indicate a wildcard. *

contexts - The context(s) from which to remove the statement. Note that this parameter is a vararg and as such is optional. If no contexts are specified the method operates on the entire repository. A null value can be used to match context-less statements.

Throws:

SailException - If the statement could not be removed.

IllegalStateException - If the connection has been closed.

clear

void clear(Resource... contexts)
           throws SailException

Removes all statements from the specified/all contexts. If no contexts are specified the method operates on the entire repository.

Parameters:

contexts - The context(s) from which to remove the statements. Note that this parameter is a vararg and as such is optional. If no contexts are specified the method operates on the entire repository. A null value can be used to match context-less statements.

Throws:

SailException - If the statements could not be removed.

IllegalStateException - If the connection has been closed.

getNamespaces

CloseableIteration<? extends Namespace,SailException> getNamespaces()
                                                                    throws SailException

Gets the namespaces relevant to the data contained in this Sail object.

Returns:

An iterator over the relevant namespaces, should not contain any duplicates.

Throws:

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

IllegalStateException - If the connection has been closed.

getNamespace

String getNamespace(String prefix)
                    throws SailException

Gets the namespace that is mapped to the specified prefix.

Parameters:

prefix - A namespace prefix.

Returns:

The namespace name that the specified prefix maps to.

Throws:

IllegalStateException - If the connection has been closed.

SailException

setNamespace

void setNamespace(String prefix,
                  String name)
                  throws SailException

Sets the prefix of a namespace.

Parameters:

prefix - The new prefix.

name - The namespace name that the prefix maps to.

Throws:

IllegalStateException - If the connection has been closed.

SailException

removeNamespace

void removeNamespace(String prefix)
                     throws SailException

Removes a namespace declaration by removing the association between a prefix and a namespace name.

Parameters:

prefix - The namespace prefix of which the assocation with a namespace name is to be removed.

Throws:

SailException - If the namespace prefix could not be removed.

IllegalStateException - If the connection has been closed.

clearNamespaces

void clearNamespaces()
                     throws SailException

Removes all namespace declarations from the repository.

Throws:

SailException - If the namespaces could not be removed.

IllegalStateException - If the connection has been closed.