org.neo4j.graphdb.traversal
Class Evaluators

java.lang.Object
  org.neo4j.graphdb.traversal.Evaluators

public abstract class Evaluators
extends Object

Common Evaluators useful during common traversals.

Author:

Mattias Persson

See Also:

Evaluator, TraversalDescription

Constructor Summary

Evaluators()

Method Summary

static Evaluator	all()
static Evaluator	atDepth(int depth) Returns an Evaluator which only includes positions at depth and prunes everything deeper than that.
static Evaluator	excludeStartPosition()
static Evaluator	fromDepth(int depth) Returns an Evaluator which only includes positions from depth and deeper and never prunes anything.
static Evaluator	includingDepths(int minDepth, int maxDepth) Returns an Evaluator which only includes positions between depths minDepth and maxDepth.
static Evaluator	lastRelationshipTypeIs(Evaluation evaluationIfMatch, Evaluation evaluationIfNoMatch, RelationshipType type, RelationshipType... orAnyOfTheseTypes) Returns an Evaluator which compares the type of the last relationship in a Path to a given set of relationship types (one or more).If the type of the last relationship in a path is of one of the given types then evaluationIfMatch will be returned, otherwise evaluationIfNoMatch will be returned.
static Evaluator	pruneWhereLastRelationshipTypeIs(RelationshipType type, RelationshipType... orAnyOfTheseTypes)
static Evaluator	returnWhereLastRelationshipTypeIs(RelationshipType type, RelationshipType... orAnyOfTheseTypes)
static Evaluator	toDepth(int depth) Returns an Evaluator which includes positions down to depth and prunes everything deeper than that.

Methods inherited from class java.lang.Object

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

Constructor Detail

Evaluators

public Evaluators()

Method Detail

all

public static Evaluator all()

Returns:

an evaluator which includes everything it encounters and doesn't prune anything.

excludeStartPosition

public static Evaluator excludeStartPosition()

Returns:

an evaluator which never prunes and includes everything except the first position, i.e. the the start node.

toDepth

public static Evaluator toDepth(int depth)

Returns an Evaluator which includes positions down to depth and prunes everything deeper than that.

Parameters:

depth - the max depth to traverse to.

Returns:

Returns an Evaluator which includes positions down to depth and prunes everything deeper than that.

fromDepth

public static Evaluator fromDepth(int depth)

Returns an Evaluator which only includes positions from depth and deeper and never prunes anything.

Parameters:

depth - the depth to start include positions from.

Returns:

Returns an Evaluator which only includes positions from depth and deeper and never prunes anything.

atDepth

public static Evaluator atDepth(int depth)

Returns an Evaluator which only includes positions at depth and prunes everything deeper than that.

Parameters:

depth - the depth to start include positions from.

Returns:

Returns an Evaluator which only includes positions at depth and prunes everything deeper than that.

includingDepths

public static Evaluator includingDepths(int minDepth,
                                        int maxDepth)

Returns an Evaluator which only includes positions between depths minDepth and maxDepth. It prunes everything deeper than maxDepth.

Parameters:

minDepth - minimum depth a position must have to be included.

maxDepth - maximum depth a position must have to be included.

Returns:

Returns an Evaluator which only includes positions between depths minDepth and maxDepth. It prunes everything deeper than maxDepth.

lastRelationshipTypeIs

public static Evaluator lastRelationshipTypeIs(Evaluation evaluationIfMatch,
                                               Evaluation evaluationIfNoMatch,
                                               RelationshipType type,
                                               RelationshipType... orAnyOfTheseTypes)

Returns an Evaluator which compares the type of the last relationship in a Path to a given set of relationship types (one or more).If the type of the last relationship in a path is of one of the given types then evaluationIfMatch will be returned, otherwise evaluationIfNoMatch will be returned.

Parameters:

evaluationIfMatch - the Evaluation to return if the type of the last relationship in the path matches any of the given types.

evaluationIfNoMatch - the Evaluation to return if the type of the last relationship in the path doesn't match any of the given types.

type - the (first) type (of possibly many) to match the last relationship in paths with.

orAnyOfTheseTypes - additional types to match the last relationship in paths with.

Returns:

an Evaluator which compares the type of the last relationship in a Path to a given set of relationship types.

returnWhereLastRelationshipTypeIs

public static Evaluator returnWhereLastRelationshipTypeIs(RelationshipType type,
                                                          RelationshipType... orAnyOfTheseTypes)

Parameters:

type - the (first) type (of possibly many) to match the last relationship in paths with.

orAnyOfTheseTypes - additional types to match the last relationship in paths with.

Returns:

an Evaluator which compares the type of the last relationship in a Path to a given set of relationship types.

See Also:

Uses {@link Evaluation#INCLUDE_AND_CONTINUE} for {@code evaluationIfMatch} and {@link Evaluation#EXCLUDE_AND_CONTINUE} for {@code evaluationIfNoMatch}.

pruneWhereLastRelationshipTypeIs

public static Evaluator pruneWhereLastRelationshipTypeIs(RelationshipType type,
                                                         RelationshipType... orAnyOfTheseTypes)

Parameters:

type - the (first) type (of possibly many) to match the last relationship in paths with.

orAnyOfTheseTypes - additional types to match the last relationship in paths with.

Returns:

an Evaluator which compares the type of the last relationship in a Path to a given set of relationship types.

See Also:

Uses {@link Evaluation#INCLUDE_AND_PRUNE} for {@code evaluationIfMatch} and {@link Evaluation#INCLUDE_AND_CONTINUE} for {@code evaluationIfNoMatch}.