Class LogicalPlanWithoutResult

java.lang.Object

se.liu.ida.hefquin.engine.queryplan.base.impl.BaseForQueryPlan

se.liu.ida.hefquin.engine.queryplan.logical.impl.LogicalPlanWithoutResult

All Implemented Interfaces:

QueryPlan, LogicalPlan

public class LogicalPlanWithoutResult
extends BaseForQueryPlan
implements LogicalPlan

This class represents a logical plan that produces the empty result.

Field Summary

Fields

Modifier and Type	Field	Description
static final ExpectedVariables	expVars
protected static final LogicalPlan	instance

Fields inherited from class se.liu.ida.hefquin.engine.queryplan.base.impl.BaseForQueryPlan

id

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	LogicalPlanWithoutResult()

Method Summary

Modifier and Type	Method	Description
ExpectedVariables	getExpectedVariables()	Returns the variables that can be expected in the solution mappings produced by this plan.
static LogicalPlan	getInstance()
LogicalOperator	getRootOperator()	Returns the root operator of this plan.
LogicalPlan	getSubPlan(int i)	Returns the i-th sub-plan of this plan, where i starts at index 0 (zero).
int	numberOfSubPlans()	Returns the number of sub-plans that this plan has (considering sub-plans that are direct children of the root operator of this plan).

Methods inherited from class se.liu.ida.hefquin.engine.queryplan.base.impl.BaseForQueryPlan

equals, getID, getQueryPlanningInfo, hashCode, hasQueryPlanningInfo

Methods inherited from class java.lang.Object

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

Methods inherited from interface se.liu.ida.hefquin.engine.queryplan.base.QueryPlan

getID, getQueryPlanningInfo, hasQueryPlanningInfo, isSamePlan

Field Details

instance

protected static final LogicalPlan instance

expVars

public static final ExpectedVariables expVars

Constructor Details

LogicalPlanWithoutResult

protected LogicalPlanWithoutResult()

Method Details

getInstance

public static LogicalPlan getInstance()

numberOfSubPlans

public int numberOfSubPlans()

Description copied from interface: QueryPlan

Returns the number of sub-plans that this plan has (considering sub-plans that are direct children of the root operator of this plan).

Specified by:

numberOfSubPlans in interface QueryPlan

getExpectedVariables

public ExpectedVariables getExpectedVariables()

Description copied from interface: QueryPlan

Returns the variables that can be expected in the solution mappings produced by this plan.

Specified by:

getExpectedVariables in interface QueryPlan

getRootOperator

public LogicalOperator getRootOperator()
                                throws NoSuchElementException

Description copied from interface: QueryPlan

Returns the root operator of this plan.

Specified by:

getRootOperator in interface LogicalPlan

Specified by:

getRootOperator in interface QueryPlan

Throws:

NoSuchElementException

getSubPlan

public LogicalPlan getSubPlan(int i)
                       throws NoSuchElementException

Description copied from interface: QueryPlan

Returns the i-th sub-plan of this plan, where i starts at index 0 (zero). If the plan has fewer sub-plans (or no sub-plans at all), then a NoSuchElementException will be thrown.

Specified by:

getSubPlan in interface LogicalPlan

Specified by:

getSubPlan in interface QueryPlan

Throws:

NoSuchElementException