classycle.graph

Class Vertex

java.lang.Object

classycle.graph.Vertex

All Implemented Interfaces:

java.lang.Comparable<Vertex>

Direct Known Subclasses:

AtomicVertex, StrongComponent

public class Vertex
extends java.lang.Object
implements java.lang.Comparable<Vertex>

The base class for any type of vertex in a directed graph.

A Vertex holds an Attributes object which encapsulates all properties of the vertex which are not necessary to know for parsing a graph in a GraphProcessor. Only the visited flag will be manipulated during parsing.

A Vertex knows the head and tail vertices of all its outgoing and incoming arcs. When a head vertex is added by the method addOutgoingArcTo(classycle.graph.Vertex) also the corresponding incoming arc is built in the head vertex. The same is true the other way around. Note, that multi-arcs are not possible. That is, adding an already added head/tail vertex again as a head/tail vertex will be ignored.

Author:

Franz-Josef Elmer

Constructor Summary

Constructors

Constructor and Description
Vertex(Attributes attributes) Create a new instance for the specified attributes.

Method Summary

Methods

Modifier and Type	Method and Description
void	addIncomingArcTo(Vertex tailVertex) Adds an incoming arc to the specified vertex.
void	addOutgoingArcTo(Vertex headVertex) Adds an outgoing arc to the specified vertex.
int	compareTo(Vertex object)
Attributes	getAttributes() Returns the attributes.
Vertex	getHeadVertex(int index) Returns the head vertex of the specified outgoing arc.
int	getNumberOfIncomingArcs() Returns the number of incoming arcs.
int	getNumberOfOutgoingArcs() Returns the number of outgoing arcs.
Vertex	getTailVertex(int index) Returns the tail vertex of the specified outgoing arc.
boolean	isVisited() Returns the visited flag.
void	reset() Reset this vertex.
java.lang.String	toString() Returns toString() of the attributes and the number of incoming and outgoing arcs.
void	visit() Marks this instance as visited.

Methods inherited from class java.lang.Object

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

Constructor Detail

Vertex

public Vertex(Attributes attributes)

Create a new instance for the specified attributes.

Method Detail

getAttributes

public Attributes getAttributes()

Returns the attributes.

getNumberOfOutgoingArcs

public int getNumberOfOutgoingArcs()

Returns the number of outgoing arcs. This is equivalent to the number of head vertices.

getHeadVertex

public Vertex getHeadVertex(int index)

Returns the head vertex of the specified outgoing arc.

addOutgoingArcTo

public void addOutgoingArcTo(Vertex headVertex)

Adds an outgoing arc to the specified vertex. Also calls addIncomingArcTo(classycle.graph.Vertex) for headVertex with this as the argument. Does nothing if headVertex is the head vertex of an already existing outgoing arc.

Parameters:

headVertex - Head vertex to be added to establish a new outgoing arc. Null is not allowed.

getNumberOfIncomingArcs

public int getNumberOfIncomingArcs()

Returns the number of incoming arcs. This is equivalent to the number of tail vertices.

getTailVertex

public Vertex getTailVertex(int index)

Returns the tail vertex of the specified outgoing arc.

addIncomingArcTo

public void addIncomingArcTo(Vertex tailVertex)

Adds an incoming arc to the specified vertex. Also calls addOutgoingArcTo(classycle.graph.Vertex) for tailVertex with this as the argument. Does nothing if tailVertex is the tail vertex of an already existing incoming arc.

Parameters:

tailVertex - Tail vertex to be added to establish a new incoming arc. Null is not allowed.

reset

public void reset()

Reset this vertex. That is, the visited flag is set to false.

visit

public void visit()

Marks this instance as visited. That is, the visited flag becomes true.

isVisited

public boolean isVisited()

Returns the visited flag.

toString

public java.lang.String toString()

Returns toString() of the attributes and the number of incoming and outgoing arcs.

Overrides:

toString in class java.lang.Object

compareTo

public int compareTo(Vertex object)

Specified by:

compareTo in interface java.lang.Comparable<Vertex>