nz.ac.waikato.jdsl.graph.api
Interface ModifiableGraph

All Superinterfaces:

Container, InspectableContainer, InspectableGraph, InspectablePositionalContainer, PositionalContainer

All Known Subinterfaces:

Graph

All Known Implementing Classes:

IncidenceListGraph

public interface ModifiableGraph
extends InspectableGraph, PositionalContainer

An interface describing the modifier methods of a combinatorial graph that can safely be inherited by more restricted graphs.

Version:

JDSL 2.1.1

Author:

Luca Vismara (lv)

See Also:

InspectableGraph

Method Summary

void	makeUndirected(Edge e) Makes a directed edge undirected.
void	reverseDirection(Edge e) Reverse the direction of an edge.
void	setDirectionFrom(Edge e, Vertex v) Sets the direction of an edge away from a vertex.
void	setDirectionTo(Edge e, Vertex v) Sets the direction of an edge towards a vertex.
Vertex	splitEdge(Edge e, java.lang.Object vertElement) Splits an existing edge by inserting a new vertex and two new edges, and removing the old edge.
Edge	unsplitEdge(Vertex v, java.lang.Object edgeElement) Transforms edge-vertex-edge into a single edge.

Methods inherited from interface nz.ac.waikato.jdsl.graph.api.InspectableGraph

aCommonVertex, aConnectingEdge, adjacentVertices, adjacentVertices, anEdge, anIncidentEdge, anIncidentEdge, areAdjacent, areAdjacent, areIncident, aVertex, connectingEdges, degree, degree, destination, directedEdges, edges, endVertices, incidentEdges, incidentEdges, isDirected, numEdges, numVertices, opposite, origin, undirectedEdges, vertices

Methods inherited from interface nz.ac.waikato.jdsl.core.api.PositionalContainer

swapElements

Methods inherited from interface nz.ac.waikato.jdsl.core.api.InspectablePositionalContainer

positions

Methods inherited from interface nz.ac.waikato.jdsl.core.api.Container

newContainer, replaceElement

Methods inherited from interface nz.ac.waikato.jdsl.core.api.InspectableContainer

contains, elements, isEmpty, size

Method Detail

splitEdge

Vertex splitEdge(Edge e,
                 java.lang.Object vertElement)
                 throws InvalidAccessorException

Splits an existing edge by inserting a new vertex and two new edges, and removing the old edge. If the edge is directed, the two new edges maintain the direction. The old edge is removed; its element() can still be retrieved. The new edges store null elements, and the new vertex stores the specified element.

Parameters:

e - the edge to be split

vertElement - the object to be stored in v

Returns:

the new vertex w; to get the new edges, use method incidentEdges(w)

Throws:

InvalidAccessorException - if the edge does not belong to this graph

unsplitEdge

Edge unsplitEdge(Vertex v,
                 java.lang.Object edgeElement)
                 throws InvalidAccessorException,
                        InvalidVertexException

Transforms edge-vertex-edge into a single edge. The vertex must be of degree 2. The edges and the vertex are removed (their element()s can still be retrieved), and a new edge is inserted in their place. The new edge stores the specified element.

If the two incident edges of v are consistently directed, the new edge is directed in that direction. If they are both undirected, the new edge is undirected. Any other combination of directions also results in an undirected edge.

Parameters:

v - the vertex to be removed

edgeElement - the element to be stored in the new edge

Returns:

the new edge

Throws:

InvalidVertexException - If the vertex is not of degree 2 or is of degree 2 but the "two" edges are a single self-loop

InvalidAccessorException - if the vertex does not belong to this graph

setDirectionFrom

void setDirectionFrom(Edge e,
                      Vertex v)
                      throws InvalidAccessorException,
                             InvalidVertexException

Sets the direction of an edge away from a vertex. Makes an undirected edge directed.

Parameters:

e - an edge

v - an endvertex of e

Throws:

InvalidVertexException - if v is not an endvertex of e but both v and e belong to this graph

InvalidAccessorException - if either e or v does not belong to this graph

setDirectionTo

void setDirectionTo(Edge e,
                    Vertex v)
                    throws InvalidAccessorException,
                           InvalidVertexException

Sets the direction of an edge towards a vertex. Makes an undirected edge directed.

Parameters:

e - an edge

v - an endvertex of e

Throws:

InvalidVertexException - if v is not an endvertex of e

InvalidAccessorException - if either e or v does not belong to this graph

makeUndirected

void makeUndirected(Edge e)
                    throws InvalidAccessorException

Makes a directed edge undirected. Does nothing if the edge is undirected.

Parameters:

e - an edge

Throws:

InvalidAccessorException - if the edge does not belong to this graph

reverseDirection

void reverseDirection(Edge e)
                      throws InvalidEdgeException,
                             InvalidAccessorException

Reverse the direction of an edge.

Parameters:

e - an edge

Throws:

InvalidEdgeException - If the edge is undirected

InvalidAccessorException - if the edge does not belong to this graph