Package org.eclipse.rdf4j.spring.support.query

Class DelegatingGraphQuery

java.lang.Object

org.eclipse.rdf4j.spring.support.query.DelegatingGraphQuery

All Implemented Interfaces:

GraphQuery, Operation, Query

Direct Known Subclasses:

LoggingGraphQuery, ResultCachingGraphQuery

public abstract class DelegatingGraphQuery
extends Object
implements GraphQuery

Since:

4.0.0

Author:

Florian Kleedorfer

Nested Class Summary

Nested classes/interfaces inherited from interface org.eclipse.rdf4j.query.Query

Query.QueryType

Constructor Summary

Constructors

Constructor	Description
DelegatingGraphQuery(GraphQuery delegate)

Method Summary

Modifier and Type	Method	Description
void	clearBindings()	Removes all previously set bindings.
GraphQueryResult	evaluate()
void	evaluate(RDFHandler handler)
Explanation	explain(Explanation.Level level)	Explain how the query will be (or has been) executed/evaluated by returning an explanation of the query plan.
BindingSet	getBindings()	Retrieves the bindings that have been set on this operation.
Dataset	getDataset()	Gets the dataset that has been set using Operation.setDataset(Dataset), if any.
protected GraphQuery	getDelegate()
boolean	getIncludeInferred()	Returns whether or not this operation will return inferred statements (if any are present in the repository).
int	getMaxExecutionTime()	Returns the maximum operation execution time.
int	getMaxQueryTime()	Deprecated.
void	removeBinding(String name)	Removes a previously set binding on the supplied variable.
void	setBinding(String name, Value value)	Binds the specified variable to the supplied value.
void	setDataset(Dataset dataset)	Specifies the dataset against which to execute an operation, overriding any dataset that is specified in the operation itself.
void	setIncludeInferred(boolean includeInferred)	Determine whether evaluation results of this operation should include inferred statements (if any inferred statements are present in the repository).
void	setMaxExecutionTime(int maxExecutionTimeSeconds)	Specifies the maximum time that an operation is allowed to run.
void	setMaxQueryTime(int maxQueryTime)	Deprecated.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Details

DelegatingGraphQuery

public DelegatingGraphQuery(GraphQuery delegate)

Method Details

getDelegate

protected GraphQuery getDelegate()

evaluate

public GraphQueryResult evaluate()
                          throws QueryEvaluationException

Specified by:

evaluate in interface GraphQuery

Throws:

QueryEvaluationException

evaluate

public void evaluate(RDFHandler handler)
              throws QueryEvaluationException,
RDFHandlerException

Specified by:

evaluate in interface GraphQuery

Throws:

QueryEvaluationException

RDFHandlerException

setMaxQueryTime

@Deprecated
public void setMaxQueryTime(int maxQueryTime)

Deprecated.

Description copied from interface: Query

Specifies the maximum time that a query is allowed to run. The query will be interrupted when it exceeds the time limit. Any consecutive requests to fetch query results will result in QueryInterruptedExceptions.

Specified by:

setMaxQueryTime in interface Query

Parameters:

maxQueryTime - The maximum query time, measured in seconds. A negative or zero value indicates an unlimited query time (which is the default).

getMaxQueryTime

@Deprecated
public int getMaxQueryTime()

Deprecated.

Description copied from interface: Query

Returns the maximum query evaluation time.

Specified by:

getMaxQueryTime in interface Query

Returns:

The maximum query evaluation time, measured in seconds.

See Also:

• Query.setMaxQueryTime(int)

explain

@Experimental
public Explanation explain(Explanation.Level level)

Description copied from interface: Query

Explain how the query will be (or has been) executed/evaluated by returning an explanation of the query plan.

This method is useful for understanding why a particular query is slow. The most useful level is Executed, but this takes as long as it takes to execute/evaluate the query.

When timing a query you should keep in mind that the query performance will vary based on how much the JIT compiler has compiled the code (C1 vs C2) and based on what is or isn't cached in memory. If Timed explanations are considerably slower than Executed explanations the overhead with timing the query may be large on your system and should not be trusted.

WARNING: This method is experimental and is subject to change or removal without warning. Same goes for the returned explanation. There is currently only partial support for this method in RDF4J and and UnsupportedOperationException where support is lacking.

Specified by:

explain in interface Query

Parameters:

level - The explanation level that should be used to create the explanation. Choose between: Unoptimized (as parsed without optimizations) , Optimized (as is actually going to be used), Executed (as was executed/evaluated, including some real performance metrics), Timed (as was executed/evaluated including all real performance metrics). Executed and Timed level can potentially be slow.

Returns:

The explanation that we generated, which can be viewed in a human readable format with toString(), as JSON or as a simplified query plan object structure.

setBinding

public void setBinding(String name,
 Value value)

Description copied from interface: Operation

Binds the specified variable to the supplied value. Any value that was previously bound to the specified value will be overwritten.

Specified by:

setBinding in interface Operation

Parameters:

name - The name of the variable that should be bound.

value - The (new) value for the specified variable.

removeBinding

public void removeBinding(String name)

Description copied from interface: Operation

Removes a previously set binding on the supplied variable. Calling this method with an unbound variable name has no effect.

Specified by:

removeBinding in interface Operation

Parameters:

name - The name of the variable from which the binding is to be removed.

clearBindings

public void clearBindings()

Description copied from interface: Operation

Removes all previously set bindings.

Specified by:

clearBindings in interface Operation

getBindings

public BindingSet getBindings()

Description copied from interface: Operation

Retrieves the bindings that have been set on this operation.

Specified by:

getBindings in interface Operation

Returns:

A (possibly empty) set of operation variable bindings.

See Also:

• Operation.setBinding(String, Value)

setDataset

public void setDataset(Dataset dataset)

Description copied from interface: Operation

Specifies the dataset against which to execute an operation, overriding any dataset that is specified in the operation itself.

Specified by:

setDataset in interface Operation

getDataset

public Dataset getDataset()

Description copied from interface: Operation

Gets the dataset that has been set using Operation.setDataset(Dataset), if any.

Specified by:

getDataset in interface Operation

setIncludeInferred

public void setIncludeInferred(boolean includeInferred)

Description copied from interface: Operation

Determine whether evaluation results of this operation should include inferred statements (if any inferred statements are present in the repository). The default setting is 'true'.

Specified by:

setIncludeInferred in interface Operation

Parameters:

includeInferred - indicates whether inferred statements should be included in the result.

getIncludeInferred

public boolean getIncludeInferred()

Description copied from interface: Operation

Returns whether or not this operation will return inferred statements (if any are present in the repository).

Specified by:

getIncludeInferred in interface Operation

Returns:

true if inferred statements will be returned, false otherwise.

setMaxExecutionTime

public void setMaxExecutionTime(int maxExecutionTimeSeconds)

Description copied from interface: Operation

Specifies the maximum time that an operation is allowed to run. The operation will be interrupted when it exceeds the time limit. Any consecutive requests to fetch query results will result in QueryInterruptedExceptions or UpdateExecutionExceptions (depending on whether the operation is a query or an update).

Specified by:

setMaxExecutionTime in interface Operation

Parameters:

maxExecutionTimeSeconds - The maximum query time, measured in seconds. A negative or zero value indicates an unlimited execution time (which is the default).

getMaxExecutionTime

public int getMaxExecutionTime()

Description copied from interface: Operation

Returns the maximum operation execution time.

Specified by:

getMaxExecutionTime in interface Operation

Returns:

The maximum operation execution time, measured in seconds.

See Also:

• Operation.setMaxExecutionTime(int)

toString

public String toString()

Overrides:

toString in class Object