Package se.liu.ida.hefquin.engine.queryplan.executable.impl.iterbased

Class ResultElementIterBase

java.lang.Object

se.liu.ida.hefquin.engine.queryplan.executable.impl.iterbased.ResultElementIterBase

All Implemented Interfaces:

Iterator<SolutionMapping>, ResultElementIterator

Direct Known Subclasses:

ResultElementIterWithBinaryExecOp, ResultElementIterWithNullaryExecOp, ResultElementIterWithUnaryExecOp

public abstract class ResultElementIterBase
extends Object
implements ResultElementIterator

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	ResultElementIterBase.OpRunnerThread

Field Summary

Fields

Modifier and Type	Field	Description
protected final ExecutionContext	execCxt
protected boolean	exhausted
protected SolutionMapping	nextElement
protected final SynchronizedIntermediateResultElementSink	sink

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ResultElementIterBase(ExecutionContext execCxt)

Method Summary

Modifier and Type	Method	Description
protected void	ensureOpRunnerThreadHasNoException()
protected void	ensureOpRunnerThreadIsStarted()
ExecutableOperator	getOp()
protected abstract ResultElementIterBase.OpRunnerThread	getOpRunnerThread()
boolean	hasNext()
SolutionMapping	next()

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, remove

Field Details

execCxt

protected final ExecutionContext execCxt

sink

protected final SynchronizedIntermediateResultElementSink sink

exhausted

protected boolean exhausted

nextElement

protected SolutionMapping nextElement

Constructor Details

ResultElementIterBase

protected ResultElementIterBase(ExecutionContext execCxt)

Method Details

hasNext

public boolean hasNext()
                throws ResultElementIterException

Specified by:

hasNext in interface Iterator<SolutionMapping>

Specified by:

hasNext in interface ResultElementIterator

Throws:

ResultElementIterException

next

public SolutionMapping next()
                     throws ResultElementIterException

Specified by:

next in interface Iterator<SolutionMapping>

Specified by:

next in interface ResultElementIterator

Throws:

ResultElementIterException

ensureOpRunnerThreadIsStarted

protected void ensureOpRunnerThreadIsStarted()

ensureOpRunnerThreadHasNoException

protected void ensureOpRunnerThreadHasNoException()
                                           throws ResultElementIterException

Throws:

ResultElementIterException

getOp

public ExecutableOperator getOp()

getOpRunnerThread

protected abstract ResultElementIterBase.OpRunnerThread getOpRunnerThread()