Package com.apple.foundationdb.record.query.predicates

Class ElementPredicate

java.lang.Object

com.apple.foundationdb.record.query.predicates.ElementPredicate

All Implemented Interfaces:

PlanHashable, Bindable, QueryPredicate

@API(EXPERIMENTAL)
public class ElementPredicate
extends Object
implements QueryPredicate

A QueryPredicate that evaluates a Comparisons.Comparison on the value of an Element.

An element predicate is a "leaf" in a predicate tree. It pairs an element, which can be evaluated with respect to a given SourceEntry, with a comparison. An element predicate evalutes to the result of the comparison on the value of the element.

Constructor Summary

Constructors

Constructor	Description
ElementPredicate(Element element, Comparisons.Comparison comparison)

Method Summary

Modifier and Type	Method	Description
Stream<PlannerBindings>	bindTo(ExpressionMatcher<? extends Bindable> matcher)	Attempt to match the matcher to this bindable object.
boolean	equals(Object o)
<M extends Message> Boolean	eval(FDBRecordStoreBase<M> store, EvaluationContext context, SourceEntry sourceEntry)
Comparisons.Comparison	getComparison()
Element	getElement()
int	hashCode()
int	planHash()	Return a hash similar to hashCode, but with the additional guarantee that is is stable across JVMs.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

ElementPredicate

public ElementPredicate(@Nonnull
                        Element element,
                        @Nonnull
                        Comparisons.Comparison comparison)

Method Detail

getComparison

@Nonnull
public Comparisons.Comparison getComparison()

getElement

@Nonnull
public Element getElement()

eval

@Nullable
public <M extends Message> Boolean eval(@Nonnull
                                        FDBRecordStoreBase<M> store,
                                        @Nonnull
                                        EvaluationContext context,
                                        @Nonnull
                                        SourceEntry sourceEntry)

Specified by:

eval in interface QueryPredicate

bindTo

@Nonnull
public Stream<PlannerBindings> bindTo(@Nonnull
                                      ExpressionMatcher<? extends Bindable> matcher)

Description copied from interface: Bindable

Attempt to match the matcher to this bindable object.

Specified by:

bindTo in interface Bindable

Parameters:

matcher - the matcher to match against

Returns:

a map of bindings if the match succeeded, or an empty Optional if it failed

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

planHash

public int planHash()

Description copied from interface: PlanHashable

Return a hash similar to hashCode, but with the additional guarantee that is is stable across JVMs.

Specified by:

planHash in interface PlanHashable

Returns:

a stable hash code