Package org.apache.tinkerpop.gremlin.process.traversal

Interface Path

All Superinterfaces:

Cloneable, Iterable<Object>

All Known Implementing Classes:

DetachedPath, EmptyPath, ImmutablePath, MutablePath, ReferencePath

public interface Path
extends Cloneable, Iterable<Object>

A Path denotes a particular walk through a Graph as defined by a Traversal. In abstraction, any Path implementation maintains two lists: a list of sets of labels and a list of objects. The list of labels are the labels of the steps traversed. The list of objects are the objects traversed.

Author:

Marko A. Rodriguez (http://markorodriguez.com)

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	Path.Exceptions

Method Summary

Modifier and Type	Method	Description
Path	clone()
Path	extend(Object object, Set<String> labels)	Add a new step to the path with an object and any number of associated labels.
Path	extend(Set<String> labels)	Add labels to the head of the path.
default void	forEach(BiConsumer<Object,Set<String>> consumer)
default <A> A	get(int index)	Get the object associated with the specified index into the path.
default <A> A	get(String label)	Get the object associated with the particular label of the path.
default <A> A	get(Pop pop, String label)	Pop the object(s) associated with the label of the path.
default boolean	hasLabel(String label)	Return true if the path has the specified label, else return false.
default <A> A	head()	Get the head of the path.
default boolean	isEmpty()	Determine if the path is empty or not.
default boolean	isSimple()	Determines whether the path is a simple or not.
default Iterator<Object>	iterator()
List<Set<String>>	labels()	An ordered list of the labels associated with the path The set of labels for a particular step are ordered by the order in which extend(Object, Set) was called.
List<Object>	objects()	An ordered list of the objects in the path.
default boolean	popEquals(Pop pop, Object other)
Path	retract(Set<String> labels)	Remove labels from path.
default int	size()	Get the number of step in the path.
default Stream<org.javatuples.Pair<Object,Set<String>>>	stream()
default Path	subPath(String fromLabel, String toLabel)	Isolate a sub-path from the path object.

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Detail

size

default int size()

Get the number of step in the path.

Returns:

the size of the path

isEmpty

default boolean isEmpty()

Determine if the path is empty or not.

Returns:

whether the path is empty or not.

head

default <A> A head()

Get the head of the path.

Type Parameters:

A - the type of the head of the path

Returns:

the head of the path

extend

Path extend(Object object,
            Set<String> labels)

Add a new step to the path with an object and any number of associated labels.

Parameters:

object - the new head of the path

labels - the labels at the head of the path

Returns:

the extended path

extend

Path extend(Set<String> labels)

Add labels to the head of the path.

Parameters:

labels - the labels at the head of the path

Returns:

the path with added labels

retract

Path retract(Set<String> labels)

Remove labels from path.

Parameters:

labels - the labels to remove

Returns:

the path with removed labels

get

default <A> A get(String label)
           throws IllegalArgumentException

Get the object associated with the particular label of the path. If the path as multiple labels of the type, then return a List of those objects.

Type Parameters:

A - the type of the object associated with the label

Parameters:

label - the label of the path

Returns:

the object associated with the label of the path

Throws:

IllegalArgumentException - if the path does not contain the label

get

default <A> A get(Pop pop,
                  String label)
           throws IllegalArgumentException

Pop the object(s) associated with the label of the path.

Type Parameters:

A - the type of the object associated with the label

Parameters:

pop - first for least recent, last for most recent, and all for all in a list

label - the label of the path

Returns:

the object associated with the label of the path

Throws:

IllegalArgumentException - if the path does not contain the label

get

default <A> A get(int index)

Get the object associated with the specified index into the path.

Type Parameters:

A - the type of the object associated with the index

Parameters:

index - the index of the path

Returns:

the object associated with the index of the path

hasLabel

default boolean hasLabel(String label)

Return true if the path has the specified label, else return false.

Parameters:

label - the label to search for

Returns:

true if the label exists in the path

objects

List<Object> objects()

An ordered list of the objects in the path.

Returns:

the objects of the path

labels

List<Set<String>> labels()

An ordered list of the labels associated with the path The set of labels for a particular step are ordered by the order in which extend(Object, Set) was called.

Returns:

the labels of the path

clone

Path clone()

isSimple

default boolean isSimple()

Determines whether the path is a simple or not. A simple path has no cycles and thus, no repeated objects.

Returns:

Whether the path is simple or not

iterator

default Iterator<Object> iterator()

Specified by:

iterator in interface Iterable<Object>

forEach

default void forEach(BiConsumer<Object,Set<String>> consumer)

stream

default Stream<org.javatuples.Pair<Object,Set<String>>> stream()

popEquals

default boolean popEquals(Pop pop,
                          Object other)

subPath

default Path subPath(String fromLabel,
                     String toLabel)

Isolate a sub-path from the path object. The isolation is based solely on the path labels. The to-label is inclusive. Thus, from "b" to "c" would isolate the example path as follows a,[b,c],d. Note that if there are multiple path segments with the same label, then its the last occurrence that is isolated. For instance, from "b" to "c" would be a,b,[b,c,d,c].

Parameters:

fromLabel - The label to start recording the sub-path from.

toLabel - The label to end recording the sub-path to.

Returns:

the isolated sub-path.