com.phoenixst.plexus.examples

Class AbstractIntegerNodeGraph

java.lang.Object

com.phoenixst.plexus.AbstractGraph

com.phoenixst.plexus.examples.AbstractIntegerNodeGraph

All Implemented Interfaces:

Graph, Serializable

Direct Known Subclasses:

CirculantGraph, CompleteGraph, CompleteTree, EmptyGraph, LoopGraph, Path, PetersenGraph

public abstract class AbstractIntegerNodeGraph
extends AbstractGraph
implements Serializable

An unmodifiable graph where the nodes are Integers from zero to a specified number (exclusive) and the edges do not contain user-defined objects. This is mainly useful for implementing special-case graphs that do not actually need to explicitly store their structure.

This implementation is simple. Any extension must also be simple to support on-the-fly Graph.Edge creation. To fully implement an extension of this class, the programmer must provide implementations for the following methods:

• createEdge( tailIndex, headIndex )
• createEdgeCollection()
• createTraverser( nodeIndex )

In addition, it is recommended that the programmer override degree( node ) (when applicable) since its default implementation inefficiently depends upon other iterator-returning methods.

Since:

1.0

Version:

$Revision: 1.8 $

Author:

Ray A. Conner

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	AbstractIntegerNodeGraph.AbstractIntegerEdgeCollection
protected static class	AbstractIntegerNodeGraph.EdgeImpl Protected Graph.Edge implementation.

Nested classes/interfaces inherited from interface com.phoenixst.plexus.Graph

Graph.Edge

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractIntegerNodeGraph(int n) Creates a new AbstractIntegerNodeGraph.

Method Summary

Methods

Modifier and Type	Method and Description
protected int	checkNode(Object node) Returns the specified node as a primitive int from 0 to the number of nodes in this graph (exclusive) if the specified node is in this graph.
boolean	containsEdge(Graph.Edge edge) Returns true if this Graph contains the specified Graph.Edge.
boolean	containsNode(Object node) Returns true if this Graph contains the specified node.
protected abstract Graph.Edge	createEdge(int tailIndex, int headIndex) If an edge exists between the specified indices, create and return it.
protected abstract Collection	createEdgeCollection() Creates the (single) collection of edges for this instance.
protected abstract Traverser	createTraverser(int nodeIndex) Creates a traverser with no filtering; assumes that the node index is valid.
protected Collection	edges() Returns a Collection view of all the Graph.Edges in this Graph.
protected int	getNodeIndex(Object node) Returns the specified node as a primitive int from 0 to the number of nodes in this graph (exclusive) if the specified node is in this graph.
protected int	getNodeSize() Returns the number of nodes in this AbstractIntegerNodeGraph.
protected Collection	nodes() Returns a Collection view of all the nodes in this Graph.
boolean	removeEdge(Graph.Edge edge) Throws an UnsupportedOperationException.
boolean	removeNode(Object node) Throws an UnsupportedOperationException.
protected Traverser	traverser(Object node) Returns an unfiltered Traverser over those Graph.Edges incident to the specified node.

Methods inherited from class com.phoenixst.plexus.AbstractGraph

addEdge, addNode, adjacentNodes, degree, degree, edges, getAdjacentNode, getEdge, getIncidentEdge, getNode, incidentEdges, nodes, traverser

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractIntegerNodeGraph

protected AbstractIntegerNodeGraph(int n)

Creates a new AbstractIntegerNodeGraph.

Method Detail

nodes

protected final Collection nodes()

Description copied from class: AbstractGraph

Returns a Collection view of all the nodes in this Graph. This method is only called by nodes( Predicate ).

Specified by:

nodes in class AbstractGraph

edges

protected final Collection edges()

Description copied from class: AbstractGraph

Returns a Collection view of all the Graph.Edges in this Graph. This method is only called by edges( Predicate ).

Specified by:

edges in class AbstractGraph

traverser

protected final Traverser traverser(Object node)

Description copied from class: AbstractGraph

Returns an unfiltered Traverser over those Graph.Edges incident to the specified node. This method is only called by traverser( node, Predicate ).

Specified by:

traverser in class AbstractGraph

removeNode

public final boolean removeNode(Object node)

Throws an UnsupportedOperationException.

Specified by:

removeNode in interface Graph

Overrides:

removeNode in class AbstractGraph

Parameters:

node - the node to be removed from this Graph.

Returns:

true if this Graph contained node.

containsNode

public final boolean containsNode(Object node)

Returns true if this Graph contains the specified node.

Specified by:

containsNode in interface Graph

Overrides:

containsNode in class AbstractGraph

Parameters:

node - the node whose presence in this Graph is to be tested.

Returns:

true if this Graph contains the specified node.

removeEdge

public final boolean removeEdge(Graph.Edge edge)

Throws an UnsupportedOperationException.

Specified by:

removeEdge in interface Graph

Overrides:

removeEdge in class AbstractGraph

Parameters:

edge - the Graph.Edge to be removed from this Graph.

Returns:

true if this Graph contained the specified Graph.Edge.

containsEdge

public boolean containsEdge(Graph.Edge edge)

Returns true if this Graph contains the specified Graph.Edge. This implementation tests the specified edge for equality with the one returned by createEdge( tailIndex, headIndex ) with the same tail and head.

Specified by:

containsEdge in interface Graph

Overrides:

containsEdge in class AbstractGraph

Parameters:

edge - the Graph.Edge whose presence in this Graph is to be tested.

Returns:

true if this Graph contains the specified Graph.Edge.

getNodeSize

protected final int getNodeSize()

Returns the number of nodes in this AbstractIntegerNodeGraph.

getNodeIndex

protected final int getNodeIndex(Object node)

Returns the specified node as a primitive int from 0 to the number of nodes in this graph (exclusive) if the specified node is in this graph. Otherwise, returns -1.

checkNode

protected final int checkNode(Object node)

Returns the specified node as a primitive int from 0 to the number of nodes in this graph (exclusive) if the specified node is in this graph. Otherwise, throws an NoSuchNodeException.

createEdge

protected abstract Graph.Edge createEdge(int tailIndex,
                    int headIndex)

If an edge exists between the specified indices, create and return it. If not, return null. The indices are assumed to represent valid nodes for this Graph.

createEdgeCollection

protected abstract Collection createEdgeCollection()

Creates the (single) collection of edges for this instance.

createTraverser

protected abstract Traverser createTraverser(int nodeIndex)

Creates a traverser with no filtering; assumes that the node index is valid.