Class StatementPatternQueryEvaluationStep.ConvertStatementToBindingSetIterator
- java.lang.Object
-
- org.eclipse.rdf4j.query.algebra.evaluation.impl.evaluationsteps.StatementPatternQueryEvaluationStep.ConvertStatementToBindingSetIterator
-
- All Implemented Interfaces:
java.lang.AutoCloseable
,CloseableIteration<BindingSet,QueryEvaluationException>
,Iteration<BindingSet,QueryEvaluationException>
- Enclosing class:
- StatementPatternQueryEvaluationStep
private static final class StatementPatternQueryEvaluationStep.ConvertStatementToBindingSetIterator extends java.lang.Object implements CloseableIteration<BindingSet,QueryEvaluationException>
Converts statements into the required bindingsets. A lot of work is done in the constructor and then uses invokedynamic code with lambdas for the actual conversion.This allows avoiding of significant work during the iteration. Which pays of if the iteration is long, otherwise it of course is an unneeded expense.
-
-
Field Summary
Fields Modifier and Type Field Description private java.util.function.BiConsumer<MutableBindingSet,Statement>
action
private boolean
closed
private QueryEvaluationContext
context
private CloseableIteration<? extends Statement,? extends QueryEvaluationException>
iteration
-
Constructor Summary
Constructors Modifier Constructor Description private
ConvertStatementToBindingSetIterator(CloseableIteration<? extends Statement,? extends QueryEvaluationException> iteration, java.util.function.BiConsumer<MutableBindingSet,Statement> action, QueryEvaluationContext context)
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
close()
Closes this iteration, freeing any resources that it is holding.private BindingSet
convert(Statement st)
boolean
hasNext()
Returns true if the iteration has more elements.BindingSet
next()
Returns the next element in the iteration.void
remove()
Removes from the underlying collection the last element returned by the iteration (optional operation).-
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
-
Methods inherited from interface org.eclipse.rdf4j.common.iteration.CloseableIteration
stream
-
-
-
-
Field Detail
-
action
private final java.util.function.BiConsumer<MutableBindingSet,Statement> action
-
context
private final QueryEvaluationContext context
-
iteration
private final CloseableIteration<? extends Statement,? extends QueryEvaluationException> iteration
-
closed
private boolean closed
-
-
Constructor Detail
-
ConvertStatementToBindingSetIterator
private ConvertStatementToBindingSetIterator(CloseableIteration<? extends Statement,? extends QueryEvaluationException> iteration, java.util.function.BiConsumer<MutableBindingSet,Statement> action, QueryEvaluationContext context)
-
-
Method Detail
-
convert
private BindingSet convert(Statement st)
-
hasNext
public boolean hasNext() throws QueryEvaluationException
Description copied from interface:Iteration
Returns true if the iteration has more elements. (In other words, returns true ifIteration.next()
would return an element rather than throwing a NoSuchElementException.)- Specified by:
hasNext
in interfaceIteration<BindingSet,QueryEvaluationException>
- Returns:
- true if the iteration has more elements.
- Throws:
QueryEvaluationException
-
next
public BindingSet next() throws QueryEvaluationException
Description copied from interface:Iteration
Returns the next element in the iteration.- Specified by:
next
in interfaceIteration<BindingSet,QueryEvaluationException>
- Returns:
- the next element in the iteration.
- Throws:
QueryEvaluationException
-
remove
public void remove() throws QueryEvaluationException
Description copied from interface:Iteration
Removes from the underlying collection the last element returned by the iteration (optional operation). This method can be called only once per call to next.- Specified by:
remove
in interfaceIteration<BindingSet,QueryEvaluationException>
- Throws:
QueryEvaluationException
-
close
public void close() throws QueryEvaluationException
Description copied from interface:CloseableIteration
Closes this iteration, freeing any resources that it is holding. If the iteration has already been closed then invoking this method has no effect.- Specified by:
close
in interfacejava.lang.AutoCloseable
- Specified by:
close
in interfaceCloseableIteration<BindingSet,QueryEvaluationException>
- Throws:
QueryEvaluationException
-
-