lu.cs.co.graph
Class Edge

java.lang.Object
  |
  +--lu.cs.co.graph.Edge

Direct Known Subclasses:

DirectedEdge, UndirectedEdge

public class Edge

extends Object

implements Comparable, Cloneable

This abstract class defines and provides fields and methods for an edge in a graph. The class is cannot be instantiated but is extended by DirectedEdge and UndirectedEdge, which can.

Field Summary

int	len The edge's length.
Vertex	u The first vertex incident to the edge.
Vertex	v The second vertex incident to the edge.

Method Summary

Object	clone() Returns a clone of this edge.
int	compareTo(Edge e) Compares the length of two edges.
int	compareTo(Object o) Compares this edge to another object.
Vertex	neighbour(Vertex v) The neighbour of a given vertex on this edge.
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

u

public Vertex u

The first vertex incident to the edge.

v

public Vertex v

The second vertex incident to the edge.

len

public int len

The edge's length.

Method Detail

clone

public Object clone()

Returns a clone of this edge. The incident vertices are cloned too, so the cloned edge has no vertices in common with the original.

Returns:

a clone of this edge

neighbour

public Vertex neighbour(Vertex v)

The neighbour of a given vertex on this edge. No matter how the edge is oriented, this returns the "other" vertex incident to the edge.

toString

public String toString()

Overrides:

toString in class Object

compareTo

public int compareTo(Object o)

Compares this edge to another object. If the object is an edge this function behaves like compareTo(Edge). Otherwise, it throws a ClassCastException (as Edges are comparable only to other edges).

Specified by:

compareTo in interface Comparable

Parameters:

o - the Object to be compared

Returns:

-1, 0, or +1, if the argument is longer than, as long as, or shorter than this edge

Throws:

ClassCastException - if the argument is not an edge

compareTo

public int compareTo(Edge e)

Compares the length of two edges.

Parameters:

e - the edge to be compared

Returns:

-1, 0, or +1, if e is longer than, as long as, or shorter than this edge