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

Interface ExpansionVisitor<S extends KeyExpressionVisitor.State>

Type Parameters:

S - the type of the state object whose actual type depends on the implementation of the concrete visitor

All Superinterfaces:

KeyExpressionVisitor<S,GraphExpansion>

All Known Implementing Classes:

PrimaryAccessExpansionVisitor, ValueIndexExpansionVisitor, ValueIndexLikeExpansionVisitor

public interface ExpansionVisitor<S extends KeyExpressionVisitor.State>
extends KeyExpressionVisitor<S,GraphExpansion>

A sub interface of KeyExpressionVisitor that fixes the return type to be a GraphExpansion and adds an API to cause the expansion of a metadata-based data access structure to a data flow graph that can then be used for matching.

Nested Class Summary

Nested classes/interfaces inherited from interface com.apple.foundationdb.record.query.plan.temp.KeyExpressionVisitor

KeyExpressionVisitor.Result, KeyExpressionVisitor.State

Method Summary

Modifier and Type	Method	Description
MatchCandidate	expand(Quantifier.ForEach baseQuantifier, KeyExpression primaryKey, boolean isReverse)	Method that expands a data structure into a data flow graph

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

getCurrentState, visitExpression, visitExpression, visitExpression, visitExpression, visitExpression, visitExpression, visitExpression

Method Detail

expand

@Nonnull
MatchCandidate expand(@Nonnull
                      Quantifier.ForEach baseQuantifier,
                      @Nullable
                      KeyExpression primaryKey,
                      boolean isReverse)

Method that expands a data structure into a data flow graph

Parameters:

baseQuantifier - a quantifier representing the base data access

primaryKey - the primary key of the data object the caller wants to access

isReverse - an indicator whether the result set is expected to be returned in reverse order

Returns:

a new MatchCandidate that can be used for matching.