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

Class GraphExpansion

java.lang.Object

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

All Implemented Interfaces:

KeyExpressionVisitor.Result

public class GraphExpansion
extends Object
implements KeyExpressionVisitor.Result

Class to abstract behavior when query expansion is applied to query components or key expressions. An object of this class represents a conglomeration for result values, predicates, quantifiers before those elements are unified and eventually find their home in a SelectExpression. Another way of thinking about this class is to conceptualize logic implemented here as a pre stage to actually creating expressions, as a builder of a SelectExpressions of sorts. The fundamental difference between a builder in the regular sense and this class is that it also provides getters to all elements and the ability to merge other GraphExpansions in a additive manner. This class also hides some data cleansing process, in particular related to potential duplicity on place holders, which must be corrected (de-duplicated) before the place holders are used in the predicates of e.g. a match candidate.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	GraphExpansion.Sealed	A sealed version of GraphExpansion that has already reconciled duplicate place holders.

Method Summary

Modifier and Type	Method	Description
QueryPredicate	asAndPredicate()
SelectExpression	buildSelectWithBase(Quantifier baseQuantifier)
static GraphExpansion	empty()
List<CorrelationIdentifier>	getPlaceholderAliases()
List<ValueComparisonRangePredicate.Placeholder>	getPlaceholders()
List<QueryPredicate>	getPredicates()
List<Quantifier>	getQuantifiers()
List<Value>	getResultValues()
static GraphExpansion	ofOthers(List<GraphExpansion> graphExpansions)
static GraphExpansion	ofPlaceholder(Value resultValue, ValueComparisonRangePredicate.Placeholder placeholder)
static GraphExpansion	ofPredicate(QueryPredicate predicate)
static GraphExpansion	ofPredicateAndQuantifier(QueryPredicate predicate, Quantifier quantifier)
static GraphExpansion	ofResultValue(Value resultValue)
GraphExpansion.Sealed	seal()	Method to seal a graph expansion in an instance of GraphExpansion.Sealed.
GraphExpansion	withPredicate(QueryPredicate predicate)

Methods inherited from class java.lang.Object

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

Method Detail

getResultValues

@Nonnull
public List<Value> getResultValues()

getPredicates

@Nonnull
public List<QueryPredicate> getPredicates()

getQuantifiers

@Nonnull
public List<Quantifier> getQuantifiers()

getPlaceholders

@Nonnull
public List<ValueComparisonRangePredicate.Placeholder> getPlaceholders()

getPlaceholderAliases

@Nonnull
public List<CorrelationIdentifier> getPlaceholderAliases()

asAndPredicate

@Nonnull
public QueryPredicate asAndPredicate()

withPredicate

@Nonnull
public GraphExpansion withPredicate(@Nonnull
                                    QueryPredicate predicate)

seal

@Nonnull
public GraphExpansion.Sealed seal()

Method to seal a graph expansion in an instance of GraphExpansion.Sealed. A sealed graph expansion is immutable and can only be used to (repeatedly) build actual expressions. A graph expansion object may contain duplicate information that have been added to it by callers. That is allowed and supported. In fact, in most cases, duplicates among e.g. QueryPredicates come from merging individual GraphExpansions into more complex ones. This method normalizes all elements beforehand in order to eventually return a sealed version of itself (which is not allowed to contain duplicates).

Returns:

a sealed graph expansion

buildSelectWithBase

@Nonnull
public SelectExpression buildSelectWithBase(Quantifier baseQuantifier)

empty

@Nonnull
public static GraphExpansion empty()

ofPredicate

@Nonnull
public static GraphExpansion ofPredicate(@Nonnull
                                         QueryPredicate predicate)

ofResultValue

@Nonnull
public static GraphExpansion ofResultValue(@Nonnull
                                           Value resultValue)

ofPlaceholder

@Nonnull
public static GraphExpansion ofPlaceholder(@Nonnull
                                           Value resultValue,
                                           @Nonnull
                                           ValueComparisonRangePredicate.Placeholder placeholder)

ofPredicateAndQuantifier

@Nonnull
public static GraphExpansion ofPredicateAndQuantifier(@Nonnull
                                                      QueryPredicate predicate,
                                                      @Nonnull
                                                      Quantifier quantifier)

ofOthers

@Nonnull
public static GraphExpansion ofOthers(@Nonnull
                                      List<GraphExpansion> graphExpansions)