Package com.apple.foundationdb.record.query.plan.temp.properties

Class ExpressionCountProperty

java.lang.Object

com.apple.foundationdb.record.query.plan.temp.properties.ExpressionCountProperty

All Implemented Interfaces:

PlannerProperty<Map<Class<? extends RelationalExpression>,Integer>>

public class ExpressionCountProperty
extends Object
implements PlannerProperty<Map<Class<? extends RelationalExpression>,Integer>>

A property that determines the sum, over all elements of a PlannerExpression tree, of the number of occurrences of specific types of RelationalExpression.

This property provides some heuristic sense of how much work is being done by a plan.

Constructor Summary

Constructors

Constructor	Description
ExpressionCountProperty(Set<Class<? extends RelationalExpression>> expressionClasses)

Method Summary

Modifier and Type	Method	Description
static int	count(Class<? extends RelationalExpression> expressionClass, RelationalExpression expression)
static int	count(Set<Class<? extends RelationalExpression>> expressionClasses, RelationalExpression expression)
static Map<Class<? extends RelationalExpression>,Integer>	evaluate(Set<Class<? extends RelationalExpression>> expressionClasses, RelationalExpression expression)
Map<Class<? extends RelationalExpression>,Integer>	evaluateAtExpression(RelationalExpression expression, List<Map<Class<? extends RelationalExpression>,Integer>> childResults)	Evaluate the property at the given expression, using the results of evaluating the property at its children.
Map<Class<? extends RelationalExpression>,Integer>	evaluateAtRef(ExpressionRef<? extends RelationalExpression> ref, List<Map<Class<? extends RelationalExpression>,Integer>> memberResults)	Evaluate the property at the given reference, using the results of evaluating the property at its members.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.apple.foundationdb.record.query.plan.temp.PlannerProperty

evaluateAtQuantifier, shouldVisit, shouldVisit, shouldVisit

Constructor Detail

ExpressionCountProperty

public ExpressionCountProperty(Set<Class<? extends RelationalExpression>> expressionClasses)

Method Detail

evaluateAtExpression

@Nonnull
public Map<Class<? extends RelationalExpression>,Integer> evaluateAtExpression(@Nonnull
                                                                                     RelationalExpression expression,
                                                                                     @Nonnull
                                                                                     List<Map<Class<? extends RelationalExpression>,Integer>> childResults)

Description copied from interface: PlannerProperty

Evaluate the property at the given expression, using the results of evaluating the property at its children. Called on nodes in the graph in visit post-order of the depth-first traversal of the graph. That is, as each expression is visited (after all of its children have been visited, if applicable), evaluateAtExpression() is called on that expression.

Specified by:

evaluateAtExpression in interface PlannerProperty<Map<Class<? extends RelationalExpression>,Integer>>

Parameters:

expression - the cursor to visit

childResults - the results of the property evaluated at the children of expression

Returns:

the value of property at the given expression

evaluateAtRef

@Nonnull
public Map<Class<? extends RelationalExpression>,Integer> evaluateAtRef(@Nonnull
                                                                              ExpressionRef<? extends RelationalExpression> ref,
                                                                              @Nonnull
                                                                              List<Map<Class<? extends RelationalExpression>,Integer>> memberResults)

Description copied from interface: PlannerProperty

Evaluate the property at the given reference, using the results of evaluating the property at its members. Called on nodes in the graph in visit post-order of the depth-first traversal of the graph. That is, as each reference is visited (after all of its members have been visited, if applicable), evaluateAtRef() is called on that reference.

Specified by:

evaluateAtRef in interface PlannerProperty<Map<Class<? extends RelationalExpression>,Integer>>

Parameters:

ref - the expression reference to visit

memberResults - the results of the property evaluated at the members of ref

Returns:

the value of property at the given reference

count

public static int count(@Nonnull
                        Class<? extends RelationalExpression> expressionClass,
                        @Nonnull
                        RelationalExpression expression)

count

public static int count(@Nonnull
                        Set<Class<? extends RelationalExpression>> expressionClasses,
                        @Nonnull
                        RelationalExpression expression)

evaluate

@Nonnull
public static Map<Class<? extends RelationalExpression>,Integer> evaluate(@Nonnull
                                                                                Set<Class<? extends RelationalExpression>> expressionClasses,
                                                                                @Nonnull
                                                                                RelationalExpression expression)