alma.acs.algorithms

Class Vertex

java.lang.Object

alma.acs.algorithms.Vertex

public class Vertex
extends java.lang.Object

A vertex of the graph that the TopologicalSort can work on.

Constructor Summary

Constructors

Constructor and Description
Vertex(java.lang.Object userObject) Constructor that wraps a node in the graph that has to be sorted.

Method Summary

Modifier and Type	Method and Description
void	addAdjacentVertex(Vertex vertex) Adds a dependent vertex to this vertex.
boolean	equals(java.lang.Object obj)
java.lang.Object	getUserObject() Returns the application's graph node that was wrapped by this vertex.
int	hashCode()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Vertex

public Vertex(java.lang.Object userObject)

Constructor that wraps a node in the graph that has to be sorted.

The userObject must implement reasonable equals() and hashCode() methods.

Parameters:

userObject - the application's graph node, to be retrieved later through getUserObject()

Method Detail

addAdjacentVertex

public void addAdjacentVertex(Vertex vertex)

Adds a dependent vertex to this vertex.

The direction of the graph is from "must occur first" to "may occur later". If node B depends on node A, then call vertexA.addAdjacentVertex(vertexB).

To use the example from Cormen, if you want to figure out in which order to put on your clothes, the vertex for socks must point to the vertex for shoes, stating that socks must be put on before you can put on your shoes, or in other words, that shoes depend on socks. So add the shoe vertex to the sock's adjacent vertex list.

Parameters:

vertex - another vertex that depends on this vertex.

getUserObject

public java.lang.Object getUserObject()

Returns the application's graph node that was wrapped by this vertex.

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object