salvo.jesus.graph

Class DirectedGraphImpl

java.lang.Object

salvo.jesus.graph.GraphImpl

salvo.jesus.graph.DirectedGraphImpl

All Implemented Interfaces:

Serializable, DirectedGraph, Graph

Direct Known Subclasses:

DirectedAcyclicGraphImpl

public class DirectedGraphImpl
extends GraphImpl
implements DirectedGraph

A directed Graph where edges have a specified direction. Edges in this graph are therefore instances of DirectedEdge.

Author:

Jesus M. Salvo Jr.

See Also:

Serialized Form

Field Summary

Fields inherited from class salvo.jesus.graph.GraphImpl

factory, traversal

Constructor Summary

Constructors

Constructor and Description
DirectedGraphImpl() Creates a new instance of an empty directed Graph.

Method Summary

Modifier and Type	Method and Description
DirectedEdge	getEdge(Vertex fromvertex, Vertex tovertex) Returns an Edge in the Graph whose origin is fromVertex and destination is toVertex.
List	getIncomingAdjacentVertices(Vertex v) Returns the vertices that are adjacent to a specified Vertex where the Edge is incoming from the specified Vertex to the adjacent vertex.
List	getIncomingEdges(Vertex v) Returns the incoming edges of a particular Vertex in the Graph.
List	getOutgoingAdjacentVertices(Vertex v) Returns the vertices that are adjacent to a specified Vertex where the Edge is outgoing from the specified Vertex to the adjacent vertex.
List	getOutgoingEdges(Vertex v) Returns the outgoing edges of a particular Vertex in the Graph.
boolean	isCycle(Vertex fromVertex) Determines if there is a cycle from Vertex fromVertex.
boolean	isPath(Vertex fromVertex, Vertex toVertex) Determines if there is a path from Vertex fromVertex to Vertex toVertex.

Methods inherited from class salvo.jesus.graph.GraphImpl

add, addEdge, addEdge, addGraphAddEdgeListener, addGraphAddVertexListener, addGraphRemoveEdgeListener, addGraphRemoveVertexListener, addListener, cloneVertices, containsEdge, containsVertex, forgetConnectedSets, getAdjacentVertices, getAdjacentVertices, getConnectedSet, getConnectedSet, getDegree, getDegree, getEdges, getEdgesCount, getEdgeSet, getGraphFactory, getTraversal, getVertexSet, getVertices, getVerticesCount, getVerticesIterator, isConnected, remove, removeEdge, removeEdges, removeGraphAddEdgeListener, removeGraphAddVertexListener, removeGraphRemoveEdgeListener, removeGraphRemoveVertexListener, removeListener, setGraphFactory, setTraversal, toString, traverse

Methods inherited from class java.lang.Object

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

Methods inherited from interface salvo.jesus.graph.Graph

add, addEdge, addEdge, addGraphAddEdgeListener, addGraphAddVertexListener, addGraphRemoveEdgeListener, addGraphRemoveVertexListener, addListener, cloneVertices, getAdjacentVertices, getAdjacentVertices, getConnectedSet, getConnectedSet, getDegree, getDegree, getEdges, getEdgesCount, getEdgeSet, getGraphFactory, getTraversal, getVertexSet, getVertices, getVerticesCount, getVerticesIterator, isConnected, remove, removeEdge, removeEdges, removeGraphAddEdgeListener, removeGraphAddVertexListener, removeGraphRemoveEdgeListener, removeGraphRemoveVertexListener, removeListener, setGraphFactory, setTraversal, traverse

Constructor Detail

DirectedGraphImpl

public DirectedGraphImpl()

Creates a new instance of an empty directed Graph. The default GraphTraversal object is an instance of DepthFirstDirectedGraphTraversal, a depth-first traversal respecting the direction of edges.

Method Detail

getOutgoingEdges

public List getOutgoingEdges(Vertex v)

Returns the outgoing edges of a particular Vertex in the Graph.

Specified by:

getOutgoingEdges in interface DirectedGraph

Parameters:

v - Vertex you want to determine its outgoing edges.

Returns:

List of outgoing edges of the specified Vertex.

getIncomingEdges

public List getIncomingEdges(Vertex v)

Returns the incoming edges of a particular Vertex in the Graph.

Specified by:

getIncomingEdges in interface DirectedGraph

Parameters:

v - Vertex you want to determine its incoming edges.

Returns:

List of incoming edges of the specified Vertex.

getOutgoingAdjacentVertices

public List getOutgoingAdjacentVertices(Vertex v)

Returns the vertices that are adjacent to a specified Vertex where the Edge is outgoing from the specified Vertex to the adjacent vertex.

Specified by:

getOutgoingAdjacentVertices in interface DirectedGraph

Parameters:

v - Vertex you want to determine its outgoing adjacent vertices.

Returns:

List of outgoing vertices adjacent to the specified Vertex.

getIncomingAdjacentVertices

public List getIncomingAdjacentVertices(Vertex v)

Returns the vertices that are adjacent to a specified Vertex where the Edge is incoming from the specified Vertex to the adjacent vertex.

Specified by:

getIncomingAdjacentVertices in interface DirectedGraph

Parameters:

v - Vertex you want to determine its incoming adjacent vertices.

Returns:

List of incoming vertices adjacent to the specified Vertex.

getEdge

public DirectedEdge getEdge(Vertex fromvertex,
                            Vertex tovertex)

Returns an Edge in the Graph whose origin is fromVertex and destination is toVertex. If there is more than one Edge that has the same origin and destination in the Graph, the first matching Edge is returned.

Specified by:

getEdge in interface DirectedGraph

Parameters:

fromVertex - Vertex that is the origin of the directed Edge

toVertex - Vertex that is the destination of the directed Edge

Returns:

Edge whose origin is fromVertex and destination is toVertex

See Also:

Edge

isPath

public boolean isPath(Vertex fromVertex,
                      Vertex toVertex)

Determines if there is a path from Vertex fromVertex to Vertex toVertex. This will not return true if the only path has at least one Edge pointing in the opposite direction of the path.

Specified by:

isPath in interface DirectedGraph

Parameters:

fromVertex - starting Vertex for the path

toVertex - ending Vertex for the path

Returns:

true if there is a path from Vertex to toVertex. false otherwise.

isCycle

public boolean isCycle(Vertex fromVertex)

Determines if there is a cycle from Vertex fromVertex. A cycle occurs when there is a path from the specified Vertex back to itself, taking into consideration that direction of the Edges along the path. This simply calls isPath(), where both parameters are the same Vertex.

Specified by:

isCycle in interface DirectedGraph

Parameters:

fromVertex - Vertex to be tested for a cycle path.

Returns:

true if there is a cycle path from fromVertex to itself.