com.phoenixst.plexus
Class GraphWrapper

java.lang.Object
  com.phoenixst.plexus.GraphWrapper

All Implemented Interfaces:

Graph, ObservableGraph

Direct Known Subclasses:

GraphTransformer

public class GraphWrapper
extends Object
implements ObservableGraph

A Graph which wraps another. If the wrapped graph does not implement ObservableGraph, then addGraphListener(com.phoenixst.plexus.GraphListener) and removeGraphListener(com.phoenixst.plexus.GraphListener) with throw UnsupportedOperationExceptions. This class is intended to be extended.

Since:

1.0

Version:

$Revision: 1.69 $

Author:

Ray A. Conner

Nested Class Summary

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

Graph.Edge

Constructor Summary

protected	GraphWrapper() This constructor, together with initialize(Graph), allows a subclass to initialize the internal state during deserialization.
	GraphWrapper(Graph delegate) Creates a new GraphWrapper.

Method Summary

Graph.Edge	addEdge(Object object, Object tail, Object head, boolean isDirected) Adds the specified edge to the Graph (optional operation).
void	addGraphListener(GraphListener listener) Adds the specified GraphListener which will be notified whenever this ObservableGraph's structure changes.
boolean	addNode(Object node) Adds node to this Graph (optional operation).
Collection	adjacentNodes(Object node, org.apache.commons.collections.Predicate traverserPredicate) Returns the nodes adjacent to the specified node for which the specified Predicate is satisfied.
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 com.phoenixst.plexus.GraphWrapper.EdgeWrapper	createEdge(Graph.Edge edge) Creates a wrapped Graph.Edge.
int	degree(Object node) Returns the degree of node, defined as the number of edges incident on node, with self-loops counted twice.
int	degree(Object node, org.apache.commons.collections.Predicate traverserPredicate) Returns the degree of node for which the specified Predicate is satisfied, defined as the number of edges incident on node that pass the predicate, with self-loops counted only once.
Collection	edges(org.apache.commons.collections.Predicate edgePredicate) Returns the Graph.Edges from this Graph that satisfy the specified predicate.
Object	getAdjacentNode(Object node, org.apache.commons.collections.Predicate traverserPredicate) This implementation returns the other endpoint of the Graph.Edge returned by getIncidentEdge(Object,Predicate) if present, otherwise it returns null.
protected Graph	getDelegate() Provides accesss to the internal state so it can be manually serialized by a subclass's writeObject() method.
Graph.Edge	getEdge(org.apache.commons.collections.Predicate edgePredicate) This implementation
Graph.Edge	getIncidentEdge(Object node, org.apache.commons.collections.Predicate traverserPredicate) This implementation
Object	getNode(org.apache.commons.collections.Predicate nodePredicate) This implementation
Collection	incidentEdges(Object node, org.apache.commons.collections.Predicate traverserPredicate) Returns the Graph.Edges incident on the specified node for which the specified Predicate is satisfied.
protected void	initialize(Graph delegateGraph) This method should only be called by subclasses during deserialization.
Collection	nodes(org.apache.commons.collections.Predicate nodePredicate) Returns the nodes from this Graph that satisfy the specified predicate.
boolean	removeEdge(Graph.Edge edge) Removes the specified Graph.Edge from this Graph (optional operation).
void	removeGraphListener(GraphListener listener) Removes a previously added GraphListener.
boolean	removeNode(Object node) Removes node from this Graph (optional operation).
Traverser	traverser(Object node, org.apache.commons.collections.Predicate traverserPredicate) This implementation
protected Object	unwrapEdgeObject(Object edgeObject) Returns an unwrapped edge Object.
protected Object	unwrapNode(Object node) Returns an unwrapped node.
protected Object	wrapEdgeObject(Object edgeObject) Returns a wrapped edge Object.
protected org.apache.commons.collections.Predicate	wrapEdgePredicate(org.apache.commons.collections.Predicate edgePredicate) Returns a wrapped edge predicate, if necessary.
protected Object	wrapNode(Object node) Returns a wrapped node.
protected org.apache.commons.collections.Predicate	wrapNodePredicate(org.apache.commons.collections.Predicate nodePredicate) Returns a wrapped node predicate, if necessary.
protected Traverser	wrapTraverser(Traverser traverser) Returns a wrapped traverser.
protected org.apache.commons.collections.Predicate	wrapTraverserPredicate(org.apache.commons.collections.Predicate traverserPredicate) Returns a wrapped traverser predicate, if necessary.

Methods inherited from class java.lang.Object

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

Constructor Detail

GraphWrapper

public GraphWrapper(Graph delegate)

Creates a new GraphWrapper.

GraphWrapper

protected GraphWrapper()

This constructor, together with initialize(Graph), allows a subclass to initialize the internal state during deserialization.

Method Detail

initialize

protected final void initialize(Graph delegateGraph)

This method should only be called by subclasses during deserialization.

getDelegate

protected final Graph getDelegate()

Provides accesss to the internal state so it can be manually serialized by a subclass's writeObject() method.

wrapNode

protected Object wrapNode(Object node)

Returns a wrapped node.

unwrapNode

protected Object unwrapNode(Object node)

Returns an unwrapped node.

wrapEdgeObject

protected Object wrapEdgeObject(Object edgeObject)

Returns a wrapped edge Object.

unwrapEdgeObject

protected Object unwrapEdgeObject(Object edgeObject)

Returns an unwrapped edge Object.

createEdge

protected com.phoenixst.plexus.GraphWrapper.EdgeWrapper createEdge(Graph.Edge edge)

Creates a wrapped Graph.Edge.

wrapTraverser

protected Traverser wrapTraverser(Traverser traverser)

Returns a wrapped traverser.

wrapNodePredicate

protected org.apache.commons.collections.Predicate wrapNodePredicate(org.apache.commons.collections.Predicate nodePredicate)

Returns a wrapped node predicate, if necessary.

wrapEdgePredicate

protected org.apache.commons.collections.Predicate wrapEdgePredicate(org.apache.commons.collections.Predicate edgePredicate)

Returns a wrapped edge predicate, if necessary.

wrapTraverserPredicate

protected org.apache.commons.collections.Predicate wrapTraverserPredicate(org.apache.commons.collections.Predicate traverserPredicate)

Returns a wrapped traverser predicate, if necessary.

addNode

public boolean addNode(Object node)

Description copied from interface: Graph

Adds node to this Graph (optional operation). Returns true if this Graph changed as a result of the call. Returns false if this Graph already contains node.

If a Graph refuses to add a particular node for any reason other than that it already contains the node, it must throw an exception (rather than returning false). This preserves the invariant that a Graph always contains the specified node after this call returns. Graph classes should clearly specify in their documentation any other restrictions on what nodes may be added.

Specified by:

addNode in interface Graph

Parameters:

node - the node to be added to this Graph.

Returns:

true if this Graph changed as a result of the call, false if this Graph already contains the specified node.

removeNode

public boolean removeNode(Object node)

Description copied from interface: Graph

Removes node from this Graph (optional operation). This method will also remove all edges incident on node.

Specified by:

removeNode in interface Graph

Parameters:

node - the node to be removed from this Graph.

Returns:

true if this Graph contained node.

containsNode

public boolean containsNode(Object node)

Description copied from interface: Graph

Returns true if this Graph contains the specified node.

Specified by:

containsNode in interface Graph

Parameters:

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

Returns:

true if this Graph contains the specified node.

addEdge

public Graph.Edge addEdge(Object object,
                          Object tail,
                          Object head,
                          boolean isDirected)

Description copied from interface: Graph

Adds the specified edge to the Graph (optional operation). Returns the newly created Graph.Edge if this Graph changed as a result of the call. Returns null if this Graph does not allow duplicate edges and already contains the specified edge.

If a Graph refuses to add a particular edge for any reason other than that it already contains the edge, it must throw an exception (rather than returning null). This preserves the invariant that a Graph always contains the specified edge after this call returns. Graph classes should clearly specify in their documentation any other restrictions on what edges may be added.

Specified by:

addEdge in interface Graph

Parameters:

object - the user-defined object to be contained in the new edge.

tail - the first endpoint of the new edge.

head - the second endpoint of the new edge.

isDirected - whether the new edge is directed.

Returns:

the newly created Graph.Edge if this Graph changed as a result of the call, null if this Graph does not allow duplicate edges and already contains the specified edge.

removeEdge

public boolean removeEdge(Graph.Edge edge)

Description copied from interface: Graph

Removes the specified Graph.Edge from this Graph (optional operation).

Specified by:

removeEdge in interface Graph

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)

Description copied from interface: Graph

Returns true if this Graph contains the specified Graph.Edge.

Specified by:

containsEdge in interface Graph

Parameters:

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

Returns:

true if this Graph contains the specified Graph.Edge.

degree

public int degree(Object node)

Description copied from interface: Graph

Returns the degree of node, defined as the number of edges incident on node, with self-loops counted twice. If this node has more than Integer.MAX_VALUE incident edges, returns Integer.MAX_VALUE.

Specified by:

degree in interface Graph

Parameters:

node - return the degree of this node.

Returns:

the degree of node.

degree

public int degree(Object node,
                  org.apache.commons.collections.Predicate traverserPredicate)

Description copied from interface: Graph

Returns the degree of node for which the specified Predicate is satisfied, defined as the number of edges incident on node that pass the predicate, with self-loops counted only once. The argument to the Predicate.evaluate() method is expected to be an OrderedPair. The first element of the OrderedPair is the specified node, the second is the Graph.Edge. If this node has more than Integer.MAX_VALUE such edges, returns Integer.MAX_VALUE.

Specified by:

degree in interface Graph

Parameters:

node - return the degree of this node for which the specified predicate is satisfied.

traverserPredicate - the predicate which the counted Graph.Edges must satisfy.

Returns:

the degree of node for which the specified predicate is satisfied.

nodes

public Collection nodes(org.apache.commons.collections.Predicate nodePredicate)

Description copied from interface: Graph

Returns the nodes from this Graph that satisfy the specified predicate.

Specified by:

nodes in interface Graph

Parameters:

nodePredicate - the predicate which the returned nodes must satisfy.

Returns:

the nodes from this Graph that satisfy the specified predicate.

edges

public Collection edges(org.apache.commons.collections.Predicate edgePredicate)

Description copied from interface: Graph

Returns the Graph.Edges from this Graph that satisfy the specified predicate.

Specified by:

edges in interface Graph

Parameters:

edgePredicate - the predicate which the returned Graph.Edges must satisfy.

Returns:

the Graph.Edges from this Graph that satisfy the specified predicate.

adjacentNodes

public Collection adjacentNodes(Object node,
                                org.apache.commons.collections.Predicate traverserPredicate)

Description copied from interface: Graph

Returns the nodes adjacent to the specified node for which the specified Predicate is satisfied. The argument to the Predicate.evaluate() method is expected to be an OrderedPair. The first element of the OrderedPair is the specified node, the second is the Graph.Edge. It should be noted that removing a node from the returned Collection merely removes one instance of it being adjacent to the specified node. In other words, a connecting Graph.Edge is removed.

Specified by:

adjacentNodes in interface Graph

Parameters:

node - return the nodes adjacent to this node for which the specified predicate is satisfied.

traverserPredicate - the predicate which the returned nodes and the traversed Graph.Edges must satisfy.

Returns:

the nodes adjacent to the specified node for which the specified predicate is satisfied.

incidentEdges

public Collection incidentEdges(Object node,
                                org.apache.commons.collections.Predicate traverserPredicate)

Description copied from interface: Graph

Returns the Graph.Edges incident on the specified node for which the specified Predicate is satisfied. The argument to the Predicate.evaluate() method is expected to be an OrderedPair. The first element of the OrderedPair is the specified node, the second is the Graph.Edge.

Specified by:

incidentEdges in interface Graph

Parameters:

node - return the Graph.Edges incident on this node for which the specified predicate is satisfied.

traverserPredicate - the predicate which the returned Graph.Edges must satisfy.

Returns:

the Graph.Edges incident on the specified node for which the specified predicate is satisfied.

getNode

public Object getNode(org.apache.commons.collections.Predicate nodePredicate)

This implementation

Specified by:

getNode in interface Graph

Parameters:

nodePredicate - the predicate which the returned node must satisfy.

Returns:

a node from this Graph that satisfies the specified predicate, or null if no such node exists.

getEdge

public Graph.Edge getEdge(org.apache.commons.collections.Predicate edgePredicate)

This implementation

Specified by:

getEdge in interface Graph

Parameters:

edgePredicate - the predicate which the returned Graph.Edge must satisfy.

Returns:

a Graph.Edge from this Graph that satisfies the specified predicate, or null if no such Graph.Edge exists.

getAdjacentNode

public Object getAdjacentNode(Object node,
                              org.apache.commons.collections.Predicate traverserPredicate)

This implementation returns the other endpoint of the Graph.Edge returned by getIncidentEdge(Object,Predicate) if present, otherwise it returns null.

Specified by:

getAdjacentNode in interface Graph

Parameters:

node - traverse to a node adjacent to this node for which the specified predicate is satisfied.

traverserPredicate - the predicate which the returned node and the traversed Graph.Edge must satisfy.

Returns:

a node adjacent to the specified node for which the specified predicate is satisfied.

getIncidentEdge

public Graph.Edge getIncidentEdge(Object node,
                                  org.apache.commons.collections.Predicate traverserPredicate)

This implementation

Specified by:

getIncidentEdge in interface Graph

Parameters:

node - traverse to a Graph.Edge incident on this node for which the specified predicate is satisfied.

traverserPredicate - the predicate which the returned Graph.Edge must satisfy.

Returns:

a Graph.Edge incident on the specified node for which the specified predicate is satisfied.

traverser

public Traverser traverser(Object node,
                           org.apache.commons.collections.Predicate traverserPredicate)

This implementation

Specified by:

traverser in interface Graph

Parameters:

node - traverse over all nodes adjacent to this node for which the specified predicate is satisfied.

traverserPredicate - the predicate which the returned nodes and their traversed Graph.Edges must satisfy.

Returns:

a Traverser from node to all adjacent nodes for which the specified predicate is satisfied.

addGraphListener

public void addGraphListener(GraphListener listener)

Adds the specified GraphListener which will be notified whenever this ObservableGraph's structure changes. If the wrapped graph does not implement ObservableGraph, then this method with throw an UnsupportedOperationException.

Specified by:

addGraphListener in interface ObservableGraph

removeGraphListener

public void removeGraphListener(GraphListener listener)

Removes a previously added GraphListener. If the wrapped graph does not implement ObservableGraph, then this method with throw an UnsupportedOperationException.

Specified by:

removeGraphListener in interface ObservableGraph