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

Class NullaryExecutableOpBase

java.lang.Object

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOps

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.NullaryExecutableOpBase

All Implemented Interfaces:

StatsProvider, ExecutableOperator, NullaryExecutableOp

Direct Known Subclasses:

BaseForExecOpRequest

public abstract class NullaryExecutableOpBase
extends BaseForExecOps
implements NullaryExecutableOp

Top-level base class for all implementations of NullaryExecutableOp. This base class handles the collection of statistics about both the processing times of the operator. To this end, it implements the major method of the NullaryExecutableOp interface, where the actual functionality to be implemented for this method needs to be provided by implementing the following abstract function in each sub-class of this base class. This functions is:

• _execute(IntermediateResultElementSink, ExecutionContext).

Field Summary

Fields

Modifier and Type	Field	Description
protected long	timeAtExecEnd
protected long	timeAtExecStart

Fields inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOps

collectExceptions

Constructor Summary

Constructors

Constructor	Description
NullaryExecutableOpBase(boolean collectExceptions)

Method Summary

Modifier and Type	Method	Description
protected abstract void	_execute(IntermediateResultElementSink sink, ExecutionContext execCxt)	Implementations of this function need to execute the algorithm of this operator and send the result elements (if any) to the given sink.
protected ExecutableOperatorStatsImpl	createStats()
final void	execute(IntermediateResultElementSink sink, ExecutionContext execCxt)	Executes this operator and sends the produced result elements (if any) to the given sink.
final ExecutableOperatorStats	getStats()
void	resetStats()

Methods inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOps

getExceptionsCaughtDuringExecution, recordExceptionCaughtDuringExecution

Methods inherited from class java.lang.Object

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

Methods inherited from interface se.liu.ida.hefquin.engine.queryplan.executable.ExecutableOperator

getExceptionsCaughtDuringExecution

Field Details

timeAtExecStart

protected long timeAtExecStart

timeAtExecEnd

protected long timeAtExecEnd

Constructor Details

NullaryExecutableOpBase

public NullaryExecutableOpBase(boolean collectExceptions)

Method Details

execute

public final void execute(IntermediateResultElementSink sink,
 ExecutionContext execCxt)
                   throws ExecOpExecutionException

Description copied from interface: NullaryExecutableOp

Executes this operator and sends the produced result elements (if any) to the given sink.

Specified by:

execute in interface NullaryExecutableOp

Throws:

ExecOpExecutionException

_execute

protected abstract void _execute(IntermediateResultElementSink sink,
 ExecutionContext execCxt)
                          throws ExecOpExecutionException

Implementations of this function need to execute the algorithm of this operator and send the result elements (if any) to the given sink. If an exception occurs during this process, then this exception needs to either be collected or be thrown, depending on whether BaseForExecOps.collectExceptions is set to true.

Throws:

ExecOpExecutionException

resetStats

public void resetStats()

Specified by:

resetStats in interface StatsProvider

getStats

public final ExecutableOperatorStats getStats()

Specified by:

getStats in interface ExecutableOperator

Specified by:

getStats in interface StatsProvider

createStats

protected ExecutableOperatorStatsImpl createStats()