Package com.complexible.common.rdf.query

Class IteratorAsQueryResult<T>

java.lang.Object

com.google.common.collect.UnmodifiableIterator<T>

com.google.common.collect.AbstractIterator<T>

com.complexible.common.rdf.query.IteratorAsQueryResult<T>

All Implemented Interfaces:

CloseableIterator<T>, AutoCloseable, Iterator<T>

Direct Known Subclasses:

IteratorAsBooleanQueryResult, IteratorAsGraphQueryResult, IteratorAsPathQueryResult, IteratorAsTupleQueryResult

public abstract class IteratorAsQueryResult<T>
extends com.google.common.collect.AbstractIterator<T>
implements CloseableIterator<T>

Base super-class for all iterator-as-query-result classes. It handles the on-success, on-failure, and on-close callbacks.

The result also optionally carries the optimized Plan that produced it (see getPlan()). The query engine always embeds the plan here — it is already computed, so this is free — which lets the server return it on request (see QueryDetail.PLAN) without a separate execution. The plan is null for results not built by the engine's normal execution path.

Author:

Pavel Klinov

Nested Class Summary

Nested classes/interfaces inherited from interface com.complexible.common.base.CloseableIterator

CloseableIterator.AbstractCloseableIterator<T>, CloseableIterator.DelegatingCloseableIterator<T>, CloseableIterator.EmptyCloseableIterator<T>

Constructor Summary

Constructors

Constructor	Description
IteratorAsQueryResult(CloseableIterator<T> theIter, Runnable theOnClose, Runnable theOnSuccess, Function<Exception,RuntimeException> theOnError)
IteratorAsQueryResult(CloseableIterator<T> theIter, Runnable theOnClose, Runnable theOnSuccess, Function<Exception,RuntimeException> theOnError, com.complexible.stardog.plan.Plan thePlan)

Method Summary

Modifier and Type	Method	Description
void	close()
protected T	computeNext()
com.complexible.stardog.plan.Plan	getPlan()	The optimized query plan that produced this result, or null if this result was not created by the query engine's normal execution path.

Methods inherited from class com.google.common.collect.AbstractIterator

endOfData, hasNext, next, peek

Methods inherited from class com.google.common.collect.UnmodifiableIterator

remove

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining, hasNext, next, remove

Constructor Details

IteratorAsQueryResult

public IteratorAsQueryResult(CloseableIterator<T> theIter,
 Runnable theOnClose,
 Runnable theOnSuccess,
 Function<Exception,RuntimeException> theOnError)

IteratorAsQueryResult

public IteratorAsQueryResult(CloseableIterator<T> theIter,
 Runnable theOnClose,
 Runnable theOnSuccess,
 Function<Exception,RuntimeException> theOnError,
 com.complexible.stardog.plan.Plan thePlan)

Method Details

getPlan

public com.complexible.stardog.plan.Plan getPlan()

The optimized query plan that produced this result, or null if this result was not created by the query engine's normal execution path. Embedding it costs nothing (the plan already exists); rendering it to a string is only done on demand, by the caller.

close

public void close()
           throws QueryExecutionFailure

Specified by:

close in interface AutoCloseable

Specified by:

close in interface CloseableIterator<T>

Throws:

QueryExecutionFailure

computeNext

protected T computeNext()

Specified by:

computeNext in class com.google.common.collect.AbstractIterator<T>