io.lacuna.bifurcan

Class Graph<V,E>

java.lang.Object

io.lacuna.bifurcan.Graph<V,E>

All Implemented Interfaces:

ICollection<IGraph<V,E>,V>, IGraph<V,E>, Iterable<V>

public class Graph<V,E>
extends Object
implements IGraph<V,E>

Constructor Summary

Constructors

Constructor and Description
Graph()
Graph(ToLongFunction<V> hashFn, BiPredicate<V,V> equalsFn)

Method Summary

Modifier and Type	Method and Description
Graph<V,E>	add(V vertex)
Graph<V,E>	clone()
E	edge(V from, V to)
Iterable<IEdge<V,E>>	edges()
boolean	equals(Object obj)
Graph<V,E>	forked() This returns a data structure which is forked, which is equivalent to Clojure's persistent data structures, also sometimes called functional or immutable.
int	hashCode()
Set<V>	in(V vertex) In an undirected graph, this is equivalent to IGraph.out(Object).
boolean	isDirected()
boolean	isLinear()
Graph<V,E>	linear() This returns a data structure which is linear, or temporarily mutable.
Graph<V,E>	link(V from, V to, E edge, BinaryOperator<E> merge)
<U> Graph<V,U>	mapEdges(Function<IEdge<V,E>,U> f)
Graph<V,E>	merge(IGraph<V,E> graph, BinaryOperator<E> merge)
Set<V>	out(V vertex) In an undirected graph, this is equivalent to IGraph.in(Object).
Graph<V,E>	remove(V vertex)
Graph<V,E>	select(ISet<V> vertices)
String	toString()
Graph<V,E>	transpose()
Graph<V,E>	unlink(V from, V to)
BiPredicate<V,V>	vertexEquality()
ToLongFunction<V>	vertexHash()
Set<V>	vertices()

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.lacuna.bifurcan.IGraph

add, indexOf, iterator, link, link, merge, nth, remove, replace, replace, size, split

Methods inherited from interface io.lacuna.bifurcan.ICollection

nth, save

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

Graph

public Graph()

Graph

public Graph(ToLongFunction<V> hashFn,
             BiPredicate<V,V> equalsFn)

Method Detail

vertices

public Set<V> vertices()

Specified by:

vertices in interface IGraph<V,E>

Returns:

the set of all vertices in the graph

edges

public Iterable<IEdge<V,E>> edges()

Specified by:

edges in interface IGraph<V,E>

Returns:

an iterator over every edge in the graph

edge

public E edge(V from,
              V to)

Specified by:

edge in interface IGraph<V,E>

Returns:

the value of the edge between from and to

in

public Set<V> in(V vertex)

Description copied from interface: IGraph

In an undirected graph, this is equivalent to IGraph.out(Object).

Specified by:

in in interface IGraph<V,E>

Returns:

the set of all incoming edges to vertex

out

public Set<V> out(V vertex)

Description copied from interface: IGraph

In an undirected graph, this is equivalent to IGraph.in(Object).

Specified by:

out in interface IGraph<V,E>

Returns:

the set of all outgoing edges from vertex

select

public Graph<V,E> select(ISet<V> vertices)

Specified by:

select in interface IGraph<V,E>

Returns:

a graph containing only the specified vertices and the edges between them

link

public Graph<V,E> link(V from,
                       V to,
                       E edge,
                       BinaryOperator<E> merge)

Specified by:

link in interface IGraph<V,E>

Parameters:

from - the source of the edge

to - the destination of the edge

edge - the value of the edge

merge - the merge function for the edge values, if an edge already exists

Returns:

a graph containing the new edge

unlink

public Graph<V,E> unlink(V from,
                         V to)

Specified by:

unlink in interface IGraph<V,E>

Returns:

a graph without any edge between from and to

add

public Graph<V,E> add(V vertex)

Specified by:

add in interface IGraph<V,E>

Returns:

a graph with vertex added

remove

public Graph<V,E> remove(V vertex)

Specified by:

remove in interface IGraph<V,E>

Returns:

a graph with vertex removed, as well as all incoming and outgoing edges

mapEdges

public <U> Graph<V,U> mapEdges(Function<IEdge<V,E>,U> f)

Specified by:

mapEdges in interface IGraph<V,E>

isLinear

public boolean isLinear()

Specified by:

isLinear in interface ICollection<IGraph<V,E>,V>

Returns:

true, if the collection is linear

isDirected

public boolean isDirected()

Specified by:

isDirected in interface IGraph<V,E>

Returns:

whether the graph is directed

transpose

public Graph<V,E> transpose()

Specified by:

transpose in interface IGraph<V,E>

Returns:

a transposed version of the graph

vertexHash

public ToLongFunction<V> vertexHash()

Specified by:

vertexHash in interface IGraph<V,E>

Returns:

the hash function for vertices

vertexEquality

public BiPredicate<V,V> vertexEquality()

Specified by:

vertexEquality in interface IGraph<V,E>

Returns:

the equality check for vertices

merge

public Graph<V,E> merge(IGraph<V,E> graph,
                        BinaryOperator<E> merge)

Specified by:

merge in interface IGraph<V,E>

forked

public Graph<V,E> forked()

Description copied from interface: ICollection

This returns a data structure which is forked, which is equivalent to Clojure's persistent data structures, also sometimes called functional or immutable. This is called "forked" because it means that multiple functions can make divergent changes to the data structure without affecting each other.

If only a single function or scope uses the data structure, it can be left as a linear data structure, which can have significant performance benefits.

If the data structure is already forked, it will simply return itself.

Specified by:

forked in interface ICollection<IGraph<V,E>,V>

Returns:

a forked form of the data structure

linear

public Graph<V,E> linear()

Description copied from interface: ICollection

This returns a data structure which is linear, or temporarily mutable. The term "linear", as used here, does not completely align with the formal definition of linear types as used in type theory. It is meant to describe the linear dataflow of the method calls, and as a converse to "forked" data structures.

If ICollection.forked() is called on a linear collection, all references to that linear collection should be discarded.

If the data structure is already linear, it will simply return itself.

Specified by:

linear in interface ICollection<IGraph<V,E>,V>

Returns:

a linear form of this data structure

hashCode

public int hashCode()

Overrides:

hashCode in class Object

clone

public Graph<V,E> clone()

Specified by:

clone in interface ICollection<IGraph<V,E>,V>

Overrides:

clone in class Object

Returns:

a cloned copy of the collection

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object