ai.grakn.graql.internal.reasoner.query

Class QueryAnswerStream

java.lang.Object

ai.grakn.graql.internal.reasoner.query.QueryAnswerStream

public class QueryAnswerStream
extends Object

Wrapper class for an answer stream providing higher level filtering facilities as well as unification and join operations.

Author:

Kasper Piskorski

Field Summary

Fields

Modifier and Type	Field and Description
static java.util.function.BiFunction<Map<VarName,Concept>,Set<VarName>,java.util.stream.Stream<Map<VarName,Concept>>>	incompleteFilterFunction
static java.util.function.BiFunction<Map<VarName,Concept>,QueryAnswers,java.util.stream.Stream<Map<VarName,Concept>>>	knownFilterFunction
static java.util.function.BiFunction<Map<VarName,Concept>,Set<NotEquals>,java.util.stream.Stream<Map<VarName,Concept>>>	nonEqualsFilterFunction
static java.util.function.BiFunction<Map<VarName,Concept>,Set<VarName>,java.util.stream.Stream<Map<VarName,Concept>>>	varFilterFunction

Constructor Summary

Constructors

Constructor and Description
QueryAnswerStream(java.util.stream.Stream<Map<VarName,Concept>> s)

Method Summary

Modifier and Type	Method and Description
QueryAnswerStream	filterIncomplete(Set<VarName> vars) filter stream by discarding answers with incomplete set of variables
QueryAnswerStream	filterKnown(QueryAnswers known) filter stream by discarding the already known ones
QueryAnswerStream	filterNonEquals(Query query) filter stream by applying NonEquals filters
QueryAnswerStream	filterVars(Set<VarName> vars) filter stream by constraining the variable set to the provided one
QueryAnswerStream	join(QueryAnswerStream stream2) perform a half-lazy join operation on two streams (this and stream2)
static java.util.stream.Stream<Map<VarName,Concept>>	join(java.util.stream.Stream<Map<VarName,Concept>> stream, java.util.stream.Stream<Map<VarName,Concept>> stream2) perform a half-lazy join operation on two streams (stream and stream2)
java.util.stream.Stream<Map<VarName,Concept>>	stream()

Methods inherited from class java.lang.Object

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

Field Detail

varFilterFunction

public static final java.util.function.BiFunction<Map<VarName,Concept>,Set<VarName>,java.util.stream.Stream<Map<VarName,Concept>>> varFilterFunction

knownFilterFunction

public static final java.util.function.BiFunction<Map<VarName,Concept>,QueryAnswers,java.util.stream.Stream<Map<VarName,Concept>>> knownFilterFunction

incompleteFilterFunction

public static final java.util.function.BiFunction<Map<VarName,Concept>,Set<VarName>,java.util.stream.Stream<Map<VarName,Concept>>> incompleteFilterFunction

nonEqualsFilterFunction

public static final java.util.function.BiFunction<Map<VarName,Concept>,Set<NotEquals>,java.util.stream.Stream<Map<VarName,Concept>>> nonEqualsFilterFunction

Constructor Detail

QueryAnswerStream

public QueryAnswerStream(java.util.stream.Stream<Map<VarName,Concept>> s)

Method Detail

stream

public java.util.stream.Stream<Map<VarName,Concept>> stream()

filterVars

public QueryAnswerStream filterVars(Set<VarName> vars)

filter stream by constraining the variable set to the provided one

Parameters:

vars - set of variable names

Returns:

filtered answers

filterKnown

public QueryAnswerStream filterKnown(QueryAnswers known)

filter stream by discarding the already known ones

Parameters:

known - set of known answers

Returns:

filtered answers

filterIncomplete

public QueryAnswerStream filterIncomplete(Set<VarName> vars)

filter stream by discarding answers with incomplete set of variables

Parameters:

vars - variable set considered complete

Returns:

filtered answers

filterNonEquals

public QueryAnswerStream filterNonEquals(Query query)

filter stream by applying NonEquals filters

Parameters:

query - query containing filters

Returns:

filtered answers

join

public QueryAnswerStream join(QueryAnswerStream stream2)

perform a half-lazy join operation on two streams (this and stream2)

Parameters:

stream2 - right operand of join operation

Returns:

joined stream

join

public static java.util.stream.Stream<Map<VarName,Concept>> join(java.util.stream.Stream<Map<VarName,Concept>> stream,
                                                                 java.util.stream.Stream<Map<VarName,Concept>> stream2)

perform a half-lazy join operation on two streams (stream and stream2)

Parameters:

stream - left operand of join operation

stream2 - right operand of join operation

Returns:

joined stream