org.jgrapht.traverse

Class AbstractGraphIterator<V,E>

java.lang.Object

org.jgrapht.traverse.AbstractGraphIterator<V,E>

Type Parameters:

V - the graph vertex type

E - the graph edge type

All Implemented Interfaces:

Iterator<V>, GraphIterator<V,E>

Direct Known Subclasses:

CrossComponentIterator, DegeneracyOrderingIterator, LexBreadthFirstIterator, MaximumCardinalityIterator, RandomWalkIterator, TopologicalOrderIterator

public abstract class AbstractGraphIterator<V,E>
extends Object
implements GraphIterator<V,E>

An empty implementation of a graph iterator to minimize the effort required to implement graph iterators.

Since:

Jul 19, 2003

Author:

Barak Naveh

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	crossComponentTraversal
protected Graph<V,E>	graph
protected int	nListeners
protected org.jgrapht.traverse.AbstractGraphIterator.FlyweightEdgeEvent<V,E>	reusableEdgeEvent
protected org.jgrapht.traverse.AbstractGraphIterator.FlyweightVertexEvent<V>	reusableVertexEvent
protected boolean	reuseEvents

Constructor Summary

Constructors

Constructor and Description
AbstractGraphIterator(Graph<V,E> graph) Create a new iterator

Method Summary

Modifier and Type	Method and Description
void	addTraversalListener(TraversalListener<V,E> l) Adds the specified traversal listener to this iterator.
protected EdgeTraversalEvent<E>	createEdgeTraversalEvent(E edge) Create an edge traversal event.
protected VertexTraversalEvent<V>	createVertexTraversalEvent(V vertex) Create a vertex traversal event.
protected void	fireConnectedComponentFinished(ConnectedComponentTraversalEvent e) Informs all listeners that the traversal of the current connected component finished.
protected void	fireConnectedComponentStarted(ConnectedComponentTraversalEvent e) Informs all listeners that a traversal of a new connected component has started.
protected void	fireEdgeTraversed(EdgeTraversalEvent<E> e) Informs all listeners that a the specified edge was visited.
protected void	fireVertexFinished(VertexTraversalEvent<V> e) Informs all listeners that a the specified vertex was finished.
protected void	fireVertexTraversed(VertexTraversalEvent<V> e) Informs all listeners that a the specified vertex was visited.
Graph<V,E>	getGraph() Get the graph being traversed.
boolean	isCrossComponentTraversal() Test whether this iterator is set to traverse the graph across connected components.
boolean	isReuseEvents() Tests whether the reuseEvents flag is set.
void	remove() Unsupported.
void	removeTraversalListener(TraversalListener<V,E> l) Removes the specified traversal listener from this iterator.
void	setCrossComponentTraversal(boolean crossComponentTraversal) Sets the cross component traversal flag - indicates whether to traverse the graph across connected components.
void	setReuseEvents(boolean reuseEvents) Sets a value the reuseEvents flag.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining, hasNext, next

Field Detail

nListeners

protected int nListeners

reusableEdgeEvent

protected final org.jgrapht.traverse.AbstractGraphIterator.FlyweightEdgeEvent<V,E> reusableEdgeEvent

reusableVertexEvent

protected final org.jgrapht.traverse.AbstractGraphIterator.FlyweightVertexEvent<V> reusableVertexEvent

graph

protected final Graph<V,E> graph

crossComponentTraversal

protected boolean crossComponentTraversal

reuseEvents

protected boolean reuseEvents

Constructor Detail

AbstractGraphIterator

public AbstractGraphIterator(Graph<V,E> graph)

Create a new iterator

Parameters:

graph - the graph

Method Detail

getGraph

public Graph<V,E> getGraph()

Get the graph being traversed.

Returns:

the graph being traversed

setCrossComponentTraversal

public void setCrossComponentTraversal(boolean crossComponentTraversal)

Sets the cross component traversal flag - indicates whether to traverse the graph across connected components.

Parameters:

crossComponentTraversal - if true traverses across connected components.

isCrossComponentTraversal

public boolean isCrossComponentTraversal()

Test whether this iterator is set to traverse the graph across connected components.

Specified by:

isCrossComponentTraversal in interface GraphIterator<V,E>

Returns:

true if traverses across connected components, otherwise false.

setReuseEvents

public void setReuseEvents(boolean reuseEvents)

Description copied from interface: GraphIterator

Sets a value the reuseEvents flag. If the reuseEvents flag is set to true this class will reuse previously fired events and will not create a new object for each event. This option increases performance but should be used with care, especially in multithreaded environment.

Specified by:

setReuseEvents in interface GraphIterator<V,E>

Parameters:

reuseEvents - whether to reuse previously fired event objects instead of creating a new event object for each event.

isReuseEvents

public boolean isReuseEvents()

Description copied from interface: GraphIterator

Tests whether the reuseEvents flag is set. If the flag is set to true this class will reuse previously fired events and will not create a new object for each event. This option increases performance but should be used with care, especially in multithreaded environment.

Specified by:

isReuseEvents in interface GraphIterator<V,E>

Returns:

the value of the reuseEvents flag.

addTraversalListener

public void addTraversalListener(TraversalListener<V,E> l)

Description copied from interface: GraphIterator

Adds the specified traversal listener to this iterator.

Specified by:

addTraversalListener in interface GraphIterator<V,E>

Parameters:

l - the traversal listener to be added.

remove

public void remove()

Description copied from interface: GraphIterator

Unsupported.

Specified by:

remove in interface Iterator<V>

Specified by:

remove in interface GraphIterator<V,E>

removeTraversalListener

public void removeTraversalListener(TraversalListener<V,E> l)

Description copied from interface: GraphIterator

Removes the specified traversal listener from this iterator.

Specified by:

removeTraversalListener in interface GraphIterator<V,E>

Parameters:

l - the traversal listener to be removed.

fireConnectedComponentFinished

protected void fireConnectedComponentFinished(ConnectedComponentTraversalEvent e)

Informs all listeners that the traversal of the current connected component finished.

Parameters:

e - the connected component finished event.

fireConnectedComponentStarted

protected void fireConnectedComponentStarted(ConnectedComponentTraversalEvent e)

Informs all listeners that a traversal of a new connected component has started.

Parameters:

e - the connected component started event.

fireEdgeTraversed

protected void fireEdgeTraversed(EdgeTraversalEvent<E> e)

Informs all listeners that a the specified edge was visited.

Parameters:

e - the edge traversal event.

fireVertexTraversed

protected void fireVertexTraversed(VertexTraversalEvent<V> e)

Informs all listeners that a the specified vertex was visited.

Parameters:

e - the vertex traversal event.

fireVertexFinished

protected void fireVertexFinished(VertexTraversalEvent<V> e)

Informs all listeners that a the specified vertex was finished.

Parameters:

e - the vertex traversal event.

createVertexTraversalEvent

protected VertexTraversalEvent<V> createVertexTraversalEvent(V vertex)

Create a vertex traversal event.

Parameters:

vertex - the vertex

Returns:

the event

createEdgeTraversalEvent

protected EdgeTraversalEvent<E> createEdgeTraversalEvent(E edge)

Create an edge traversal event.

Parameters:

edge - the edge

Returns:

the event