Package dev.hypera.chameleon.util.graph

Interface Graph<T>

Type Parameters:

T - Node type.

public interface Graph<T>

Graph.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	Graph.Builder<T>	Graph builder.

Method Summary

Modifier and Type	Method	Description
boolean	addNode(T node)	Adds node to this graph, if it is not already present.
@NotNull Collection<T>	adjacentNodes(T node)	Returns the nodes which have an edge with node in this graph.
static <T> @NotNull Graph.Builder<T>	directed()	Create a new directed graph builder.
@NotNull Collection<Edge<T>>	edges()	Returns all edges in this graph.
@NotNull Collection<T>	nodes()	Returns all nodes in this graph.
@NotNull Collection<T>	predecessors(T node)	Returns the nodes in this graph that have an edge with node as a target.
boolean	putEdge(@NotNull Edge<T> edge)	Adds an edge connecting Edge.source() and Edge.target(), if not already present.
default boolean	putEdge(T source, T target)	Adds an edge connecting source and target, if not already present.
boolean	removeEdge(@NotNull Edge<T> edge)	Removes the edge connecting Edge.source() and Edge.target(), if present.
default boolean	removeEdge(T source, T target)	Removes the edge connecting source and target, if present.
boolean	removeNode(T node)	Removes node from this graph, if it is present.
@NotNull Collection<T>	successors(T node)	Returns the nodes in this graph that have an edge with node as a source.

Method Detail

directed

@Contract(value="-> new",
          pure=true)
@NotNull
static <T> @NotNull Graph.Builder<T> directed()

Create a new directed graph builder.

Type Parameters:

T - Graph node type.

Returns:

new builder.

nodes

@Contract(value="-> _",
          pure=true)
@NotNull
@NotNull Collection<T> nodes()

Returns all nodes in this graph.

Returns:

graph nodes.

edges

@Contract(value="-> _",
          pure=true)
@NotNull
@NotNull Collection<Edge<T>> edges()

Returns all edges in this graph.

Returns:

graph edges.

adjacentNodes

@Contract(value="_ -> _",
          pure=true)
@NotNull
@NotNull Collection<T> adjacentNodes(@NotNull
                                     T node)

Returns the nodes which have an edge with node in this graph.

This is equivalent to the union of predecessors(Object) and successors(Object)

Parameters:

node - Node.

Returns:

adjacent nodes to node.

predecessors

@Contract(value="_ -> _",
          pure=true)
@NotNull
@NotNull Collection<T> predecessors(@NotNull
                                    T node)

Returns the nodes in this graph that have an edge with node as a target.

In an undirected graph this is equivalent to adjacentNodes(Object).

Parameters:

node - Node to get predecessors.

Returns:

predecessors to node.

successors

@Contract(value="_ -> _",
          pure=true)
@NotNull
@NotNull Collection<T> successors(@NotNull
                                  T node)

Returns the nodes in this graph that have an edge with node as a source.

In an undirected graph this is equivalent to adjacentNodes(Object).

Parameters:

node - Node to get successors of.

Returns:

successors to node.

addNode

@Contract("_ -> _")
boolean addNode(@NotNull
                T node)

Adds node to this graph, if it is not already present.

Parameters:

node - Node to be added.

Returns:

true if the graph changed as a result of this call.

removeNode

@Contract("_ -> _")
boolean removeNode(@NotNull
                   T node)

Removes node from this graph, if it is present.

All edges connecting to node will also be removed.

Parameters:

node - Node to be removed.

Returns:

true if the graph changed as a result of this call.

putEdge

@Contract("_, _ -> _")
default boolean putEdge(@NotNull
                        T source,
                        @NotNull
                        T target)

Adds an edge connecting source and target, if not already present.

If this graph is directed, the edge will also be directed; otherwise it will be undirected.

Parameters:

source - Source node.

target - Target node.

Returns:

true if the graph changed as a result of this call.

Throws:

IllegalArgumentException - if this graph does not allow self-loops and this edge is a self-loop.

putEdge

@Contract("_ -> _")
boolean putEdge(@NotNull
                @NotNull Edge<T> edge)

Adds an edge connecting Edge.source() and Edge.target(), if not already present.

If this graph is directed, the edge will also be directed; otherwise it will be undirected.

Parameters:

edge - Edge to be added.

Returns:

true if the graph changed as a result of this call.

Throws:

IllegalArgumentException - if this graph does not allow self-loops and this edge is a self-loop.

removeEdge

@Contract("_, _ -> _")
default boolean removeEdge(@NotNull
                           T source,
                           @NotNull
                           T target)

Removes the edge connecting source and target, if present.

Parameters:

source - Source node.

target - Target node.

Returns:

true if the graph changed as a result of this call.

removeEdge

@Contract("_ -> _")
boolean removeEdge(@NotNull
                   @NotNull Edge<T> edge)

Removes the edge connecting Edge.source() and Edge.target(), if present.

Parameters:

edge - Edge to be removed.

Returns:

true if the graph changed as a result of this call.