org.mathIT.graphs

Class Edge<V extends Vertible<V>>

java.lang.Object

org.mathIT.graphs.Edge<V>

Type Parameters:

V - Vertex type

public class Edge<V extends Vertible<V>>
extends Object

Objects of this class represent edges of general graphs. Although an edge of this class does not play the fundamental role internally in the math IT graph framework (edges are represented primarily on the adjacency matrix matrix of the Graph class), it is needed as basis for some additional tasks, e.g., graph visualization.

Version:

1.0

Author:

Andreas de Vries

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	directed Flag indicating whether this edge is directed.
protected V	end The end vertex of this edge.
protected String	label The label of thius graph.
protected V	start The start vertex of this edge.
protected double	weight The weight of this edge.
protected boolean	weighted Flag indicating whether this edge is directed.

Constructor Summary

Constructors

Constructor and Description
Edge(String label, V startVertex, V endVertex)
Edge(String label, V startVertex, V endVertex, boolean directed)
Edge(String label, V startVertex, V endVertex, boolean directed, double weight)
Edge(V startVertex, V endVertex) Creates a directed edge with the specified vertices.
Edge(V v, V w, boolean directed) Creates an edge with the specified properties.
Edge(V startVertex, V endVertex, boolean directed, double weight) Creates a weighted edge with the specified properties.

Method Summary

Modifier and Type	Method and Description
V	getEndVertex() Returns the end vertex of this edge.
V	getStartVertex() Returns the start vertex of this edge.
double	getWeight() Returns the weight of this edge.
boolean	isDirected() Returns true if and only if this edge is directed.
boolean	isWeighted() Returns true if and only if this edge is weighted.
String	toString() Returns the label of this edge, or the weight if the edge is weighted.

Methods inherited from class java.lang.Object

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

Field Detail

label

protected String label

The label of thius graph.

start

protected V extends Vertible<V> start

The start vertex of this edge.

end

protected V extends Vertible<V> end

The end vertex of this edge.

directed

protected boolean directed

Flag indicating whether this edge is directed.

weighted

protected boolean weighted

Flag indicating whether this edge is directed.

weight

protected double weight

The weight of this edge. It is zero by default.

Constructor Detail

Edge

public Edge(V startVertex,
            V endVertex)

Creates a directed edge with the specified vertices. The label is specified as the string "(v_s,v_e)" where v_s denotes the start vertex and v_e the end vertex.

Parameters:

startVertex - the start vertex of this edge

endVertex - the end vertex of this edge

Edge

public Edge(V v,
            V w,
            boolean directed)

Creates an edge with the specified properties. The label is specified as the string "(v, w)" if the edge is directed, and as the string "{v, w}" if the edge is undirected,

Parameters:

v - the start vertex of this edge

w - the end vertex of this edge

directed - flag indicating whether this edge is directed

Edge

public Edge(String label,
            V startVertex,
            V endVertex)

Parameters:

label - the label of this edge

startVertex - the start vertex of this edge

endVertex - the end vertex of this edge

Edge

public Edge(String label,
            V startVertex,
            V endVertex,
            boolean directed)

Parameters:

label - the label of this edge

startVertex - the start vertex of this edge

endVertex - the end vertex of this edge

directed - flag indicating whether this edge is directed

Edge

public Edge(V startVertex,
            V endVertex,
            boolean directed,
            double weight)

Creates a weighted edge with the specified properties. The label is set to the weight.

Parameters:

startVertex - the start vertex of this edge

endVertex - the end vertex of this edge

directed - flag indicating whether this edge is directed

weight - the weight of this edge

Edge

public Edge(String label,
            V startVertex,
            V endVertex,
            boolean directed,
            double weight)

Parameters:

label - the label of this edge

startVertex - the start vertex of this edge

endVertex - the end vertex of this edge

directed - flag indicating whether this edge is directed

weight - the weight of this edge

Method Detail

getStartVertex

public V getStartVertex()

Returns the start vertex of this edge.

Returns:

the start vertex of this edge

getEndVertex

public V getEndVertex()

Returns the end vertex of this edge.

Returns:

the end vertex of this edge

isDirected

public boolean isDirected()

Returns true if and only if this edge is directed.

Returns:

true if and only if this edge is directed

isWeighted

public boolean isWeighted()

Returns true if and only if this edge is weighted.

Returns:

true if and only if this edge is weighted

getWeight

public double getWeight()
                 throws IllegalArgumentException

Returns the weight of this edge.

Returns:

the weight of this edge

Throws:

IllegalArgumentException - if this method is called in case of an unweighted edge

toString

public String toString()

Returns the label of this edge, or the weight if the edge is weighted.

Overrides:

toString in class Object

Returns:

the label of this edge or the weight if the edge is weighted