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

Class RepeatedFieldSource

java.lang.Object

com.apple.foundationdb.record.query.plan.temp.view.Source

com.apple.foundationdb.record.query.plan.temp.view.RepeatedFieldSource

@API(value=EXPERIMENTAL)
public class RepeatedFieldSource
extends Source

A Source representing the stream of the zero or more values of a repeated field.

Encapsulates the logic for fanning-out the values of the repeated field and ensuring that the planner uses repeated fields in the correct way. In particular, the supportsSourceIn(ViewExpressionComparisons, Source) method ensures that multiple comparisons are associated with this source only if they can refer to the same iteration over the elements of the repeated field.

Constructor Summary

Constructors

Constructor and Description
RepeatedFieldSource(Source source, List<String> fieldNames)
RepeatedFieldSource(Source source, String fieldName)

Method Summary

Modifier and Type	Method and Description
Stream<SourceEntry>	evalSourceEntriesFor(SourceEntry parentEntry) Produce the stream of source entries that this source represents, drawing the values for dependent sources from the given source entry if needed.
List<String>	getFieldNames()
Source	getParent()
Set<Source>	getSources() Get the set of all sources of ancestor's of this source, include this source itself.
boolean	supportsSourceIn(ViewExpressionComparisons comparisons, Source other) Check whether this source can be replaced by the given source in the given ViewExpressionComparisons.
String	toString()
Source	withSourceMappedInto(Source originalSource, Source duplicateSource) Replace the given duplicate source with the given original source everywhere that it occurs in this source, including in ancestor sources.

Methods inherited from class com.apple.foundationdb.record.query.plan.temp.view.Source

addDependentSource, equals, evalSourceEntriesFor, hashCode

Methods inherited from class java.lang.Object

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

Constructor Detail

RepeatedFieldSource

public RepeatedFieldSource(@Nonnull
                           Source source,
                           @Nonnull
                           String fieldName)

RepeatedFieldSource

public RepeatedFieldSource(@Nonnull
                           Source source,
                           @Nonnull
                           List<String> fieldNames)

Method Detail

getFieldNames

@Nonnull
public List<String> getFieldNames()

getSources

public Set<Source> getSources()

Description copied from class: Source

Get the set of all sources of ancestor's of this source, include this source itself.

Specified by:

getSources in class Source

Returns:

a set of the sources of all (inclusive) ancestors of this source

getParent

@Nonnull
public Source getParent()

supportsSourceIn

public boolean supportsSourceIn(@Nonnull
                                ViewExpressionComparisons comparisons,
                                @Nonnull
                                Source other)

Description copied from class: Source

Check whether this source can be replaced by the given source in the given ViewExpressionComparisons. In general, this source can be replaced by the given source if and only if:

• The sources match each other "structurally" (i.e., differ only in a pointer-equality sense).
• The elements with comparisons in the ViewExpressionComparisons do not use this source.

Specified by:

supportsSourceIn in class Source

Parameters:

comparisons - a view expression comparisons that specifies which sources are used and unused

other - a candidate replacement for this source

Returns:

whether this source can be replaced by other

See Also:

Source.withSourceMappedInto(Source, Source), Element.matchSourcesWith(ViewExpressionComparisons, Element)

withSourceMappedInto

@Nonnull
public Source withSourceMappedInto(@Nonnull
                                            Source originalSource,
                                            @Nonnull
                                            Source duplicateSource)

Description copied from class: Source

Replace the given duplicate source with the given original source everywhere that it occurs in this source, including in ancestor sources.

Specified by:

withSourceMappedInto in class Source

Parameters:

originalSource - a source to replace all occurrences of the duplicate source with

duplicateSource - a source to replace with the original source

Returns:

a copy of this source with all occurrences of the duplicate source replaced with the original source

evalSourceEntriesFor

@Nonnull
public Stream<SourceEntry> evalSourceEntriesFor(@Nonnull
                                                         SourceEntry parentEntry)

Description copied from class: Source

Produce the stream of source entries that this source represents, drawing the values for dependent sources from the given source entry if needed.

Specified by:

evalSourceEntriesFor in class Source

Parameters:

parentEntry - a source entry to draw the input for this source from

Returns:

a stream of source entries, each of which has a value associated with this source

toString

public String toString()

Overrides:

toString in class Object