com.hedgehog.math.graph_tree
Class GraphTreeNode<NodeType>

java.lang.Object
  com.hedgehog.HObject
      com.hedgehog.math.graph_tree.GraphTreeNode<NodeType>

Type Parameters:

NodeType - Node type.

All Implemented Interfaces:

ModelObject, java.lang.Comparable, java.util.Comparator

Direct Known Subclasses:

UndirectedGraphTreeNode

public class GraphTreeNode<NodeType>
extends HObject
implements ModelObject

Title: GraphTreeNode - represents a node in a graph or tree.

Description: Models a node in a graph or tree as a node object and list of adjacent nodes.

Copyright: Copyright (c) Hedgehog Software 2007-2009.

Company: Hedgehog Software.

Since:

1.0

Version:

1.1

Field Summary

protected java.util.ArrayList<GraphTreeNode<NodeType>>	mAdjacentNodes List of adjacent nodes.
protected NodeType	nodeObject Node object.

Fields inherited from class com.hedgehog.HObject

mID, mName

Constructor Summary

GraphTreeNode()
Default constructor.

GraphTreeNode(GraphTreeNode<NodeType> object)
Copy constructor.

GraphTreeNode(NodeType nodeObject)
Constructor.

GraphTreeNode(NodeType nodeObject, java.util.ArrayList<GraphTreeNode<NodeType>> adjacentNodes)
Constructor.

Method Summary

boolean	addAdjacentNode(GraphTreeNode<NodeType> adjacentNode) Adds the specified adjacent node.
int[]	adjacentNodeIDs() Returns an integer array of the IDs of adjacent nodes to this node.
int[]	adjacentNodeObjectIDs() Returns an integer array of the IDs of the node objects of adjacent nodes to this node.
java.util.Vector<ModelObject>	childModelObjects() Returns a vector of this object's child ModelObject objects.
java.sql.PreparedStatement	databaseInsertStatement(java.sql.Connection connection, int modelID) Returns a prepared statement for inserting (INSERT command) a ModelObject object into a database.
java.sql.PreparedStatement	databaseUpdateStatement(java.sql.Connection connection, int modelID) Returns a prepared statement for updating (UPDATE command) a ModelObject object into a database.
int	degree() Returns the degree of a node; ie the number of adjacent nodes.
void	deleteAdjacencies() Deletes all adjacency relationships from this node.
boolean	deleteAdjacentNode(GraphTreeNode<NodeType> adjacentNode) Deletes the specified adjacent node.
boolean	equalNodeObjects(GraphTreeNode node) Tests whether or not two nodes are equal using the equals() method on the node objects.
boolean	equals(java.lang.Object object) Compares the specified object against this node.
ModelObject	fromDatabase(java.sql.Connection connection, Model model, int modelID, int objectID) Returns a model object from the specified database table.
ModelObject	fromXMLNode(org.w3c.dom.Document document, org.w3c.dom.Node documentRootNode, org.w3c.dom.Node node, Model model) Returns a model object from the specified xml node.
java.util.ArrayList<GraphTreeNode<NodeType>>	getAdjacentNodes() Returns the linked list of adjacnt nodes.
java.awt.Color	getNodeColour() Returns the node colour.
int	getNodeDepth() Returns the node depth.
int	getNodeFinish() Returns the node finish time.
NodeType	getNodeObject() Returns the node object.
GraphTreeNode<NodeType>	getNodePredecessor() Returns the predecessor node.
java.lang.String	getNodeType() Returns the string equivalent of the generic type of the node object; eg "ModelDouble" in GraphTreeNode.
boolean	hasAdjacentNodes() Tests whether or not a node has a list of adjacent nodes.
int	hashCode() Returns the hash code of this node.
boolean	hasMultipleArcs() Returns logical-true if a node has multiple arcs, ie the same node appears more than once in a node's adjacency list.
boolean	hasNodeObject() Tests whether or not a node has a node object.
boolean	isAdjacentNode(GraphTreeNode node) Returns logical-true if node is an adjacent node, else logical-false.
boolean	isLoopNode() Returns logical-true if the operated-on node is a loop node (i.e.
boolean	isSimple() Returns logical-true if a node is simple (i.e.
int	numberOfAdjacentNodes() Returns the number of adjacent nodes.
boolean	setAdjacentNodes(java.util.ArrayList<GraphTreeNode<NodeType>> newAdjacentNodes) Sets the adjacent nodes.
boolean	setNodeColour(java.awt.Color newColour) Sets the node colour used by breadth/depth first search iterators.
boolean	setNodeDepth(int newDepth) Sets the node depth.
boolean	setNodeFinish(int newFinish) Sets the node finish time.
boolean	setNodeObject(NodeType newNodeObject) Sets the node object.
boolean	setNodePredecessor(GraphTreeNode<NodeType> newPredecessor)
java.lang.String	toString() Returns a String representation of a GraphTreeNode object.
X3DNode	toX3DNode(X3DObject x3dObject) X3D support.
org.w3c.dom.Element	toXMLNode(org.w3c.dom.Document document, org.w3c.dom.Element documentRootNode) Returns the xml node of this object.

Methods inherited from class com.hedgehog.HObject

clone, compare, compareTo, copy, getID, getName, hasID, hasName, setID, setName

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

nodeObject

protected NodeType nodeObject

Node object.

mAdjacentNodes

protected java.util.ArrayList<GraphTreeNode<NodeType>> mAdjacentNodes

List of adjacent nodes.

Constructor Detail

GraphTreeNode

public GraphTreeNode()

Default constructor. Sets the node object to null and creates a new non-null adjacency list.

GraphTreeNode

public GraphTreeNode(NodeType nodeObject)

Constructor. Sets the node object to the specified object and creates a new non-null adjacency list.

Parameters:

nodeObject - Node object.

GraphTreeNode

public GraphTreeNode(NodeType nodeObject,
                     java.util.ArrayList<GraphTreeNode<NodeType>> adjacentNodes)

Constructor. Sets the node object and adjacency list to the specified objects.

Parameters:

nodeObject - Node object.

adjacentNodes - LinkedList of adjacent nodes.

GraphTreeNode

public GraphTreeNode(GraphTreeNode<NodeType> object)

Copy constructor.

Parameters:

object - Object to copy.

Method Detail

addAdjacentNode

public boolean addAdjacentNode(GraphTreeNode<NodeType> adjacentNode)

Adds the specified adjacent node.

Parameters:

adjacentNode - Adjacent node to be added.

Returns:

Logical-false if node added, else logical-false. Logical-false is also returned if the specified argument is null.

degree

public int degree()

Returns the degree of a node; ie the number of adjacent nodes.

Returns:

Returns the degree of a node.

deleteAdjacentNode

public boolean deleteAdjacentNode(GraphTreeNode<NodeType> adjacentNode)

Deletes the specified adjacent node.

Parameters:

adjacentNode - Adjacent node to be deleted from the operated-on node's adjacency list.

Returns:

Logical-false if adjacentNode is deleted, else logical-false. Logical-false is also returned if the specified argument is null.

deleteAdjacencies

public void deleteAdjacencies()

Deletes all adjacency relationships from this node.

getNodeObject

public NodeType getNodeObject()

Returns the node object.

Returns:

The node object.

getAdjacentNodes

public java.util.ArrayList<GraphTreeNode<NodeType>> getAdjacentNodes()

Returns the linked list of adjacnt nodes.

Returns:

The list of adjacent nodes.

adjacentNodeIDs

public int[] adjacentNodeIDs()

Returns an integer array of the IDs of adjacent nodes to this node.

Returns:

An integer array of the IDs of adjacent nodes to this node.

adjacentNodeObjectIDs

public int[] adjacentNodeObjectIDs()

Returns an integer array of the IDs of the node objects of adjacent nodes to this node.

Returns:

An integer array of the IDs of the node objects of adjacent nodes to this node.

hasNodeObject

public boolean hasNodeObject()

Tests whether or not a node has a node object.

Returns:

Logical-true if a node has a non-null node object, else logical-false.

hasAdjacentNodes

public boolean hasAdjacentNodes()

Tests whether or not a node has a list of adjacent nodes.

Returns:

Logical-true if a node has a non-null or non-empty list of adjacent nodes.

hasMultipleArcs

public boolean hasMultipleArcs()

Returns logical-true if a node has multiple arcs, ie the same node appears more than once in a node's adjacency list. Uses the equals() method to perform the node object comparison.

Returns:

Logical-true if a node has multiple arcs, else logical-false.

isLoopNode

public boolean isLoopNode()

Returns logical-true if the operated-on node is a loop node (i.e. an arc with identical end nodes, in other words the node is in its own adjacency list).

Returns:

Logical-true if node is a loop node, else logical-false.

isSimple

public boolean isSimple()

Returns logical-true if a node is simple (i.e. no multiple or self-loop arcs).

Returns:

Logical-true if node is a simple node, else logical-false.

equalNodeObjects

public boolean equalNodeObjects(GraphTreeNode node)

Tests whether or not two nodes are equal using the equals() method on the node objects.

Parameters:

node - Comparison node.

Returns:

Logiacl-true if the two nodes are the same, else logical-false.

equals

public boolean equals(java.lang.Object object)

Compares the specified object against this node. Calls equalNodeObjects() for th enode objects.

Specified by:

equals in interface java.util.Comparator

Overrides:

equals in class HObject

Parameters:

object - Object to compare.

Returns:

Logical-true if the specified object is equal to this object, else logical-false.

hashCode

public int hashCode()

Returns the hash code of this node. Simply returns the hash code of the encapsulatd node object.

Overrides:

hashCode in class HObject

Returns:

The hash code of this node.

isAdjacentNode

public boolean isAdjacentNode(GraphTreeNode node)

Returns logical-true if node is an adjacent node, else logical-false.

Parameters:

node - Test node.

Returns:

Logical-true if nde is adjacent, else logical-false.

numberOfAdjacentNodes

public int numberOfAdjacentNodes()

Returns the number of adjacent nodes.

Returns:

The number of adjacent nodes.

setNodeObject

public boolean setNodeObject(NodeType newNodeObject)

Sets the node object.

Parameters:

newNodeObject - New node object.

Returns:

Logical-rue if node object set, else logical-false.

setAdjacentNodes

public boolean setAdjacentNodes(java.util.ArrayList<GraphTreeNode<NodeType>> newAdjacentNodes)

Sets the adjacent nodes.

Parameters:

newAdjacentNodes - New linked list of adjacent nodes.

Returns:

Logical-true if new adjacency list set, else logical-false.

toString

public java.lang.String toString()

Returns a String representation of a GraphTreeNode object.

Overrides:

toString in class java.lang.Object

Returns:

A String representation of a GraphTreeNode object.

getNodeDepth

public int getNodeDepth()

Returns the node depth.

Returns:

The node depth.

getNodeColour

public java.awt.Color getNodeColour()

Returns the node colour.

Returns:

The node colour.

getNodePredecessor

public GraphTreeNode<NodeType> getNodePredecessor()

Returns the predecessor node.

Returns:

The predecessor node.

setNodeDepth

public boolean setNodeDepth(int newDepth)

Sets the node depth.

Parameters:

newDepth - New depth.

Returns:

Logical-true if new depth set(>=0), else logical-false(<0).

getNodeFinish

public int getNodeFinish()

Returns the node finish time.

Returns:

The node finish time.

setNodeFinish

public boolean setNodeFinish(int newFinish)

Sets the node finish time.

Parameters:

newFinish - New finish time.

Returns:

Logical-true if new finish set(>=0), else logical-false(<0).

setNodeColour

public boolean setNodeColour(java.awt.Color newColour)

Sets the node colour used by breadth/depth first search iterators.

Parameters:

newColour - New colour value.

Returns:

Returns logical-true if new colour set, else logical-false.

setNodePredecessor

public boolean setNodePredecessor(GraphTreeNode<NodeType> newPredecessor)

Parameters:

newPredecessor - New predecessor. Can be null, indicating that a node does not have a predcessor.

Returns:

Logiacl-true if the predecessor node is set, else logical-false.

childModelObjects

public java.util.Vector<ModelObject> childModelObjects()

Returns a vector of this object's child ModelObject objects.

Specified by:

childModelObjects in interface ModelObject

Returns:

A vector consisting of this object's node object.

databaseInsertStatement

public java.sql.PreparedStatement databaseInsertStatement(java.sql.Connection connection,
                                                          int modelID)
                                                   throws java.sql.SQLException

Returns a prepared statement for inserting (INSERT command) a ModelObject object into a database.

Specified by:

databaseInsertStatement in interface ModelObject

Parameters:

connection - Database connection.

modelID - Model ID.

Returns:

A prepared statement for inserting a ModelObject object into a database.

Throws:

java.sql.SQLException - Thrown if an SQL exception occurs.

databaseUpdateStatement

public java.sql.PreparedStatement databaseUpdateStatement(java.sql.Connection connection,
                                                          int modelID)
                                                   throws java.sql.SQLException

Returns a prepared statement for updating (UPDATE command) a ModelObject object into a database.

Specified by:

databaseUpdateStatement in interface ModelObject

Parameters:

connection - Database connection.

modelID - Model ID.

Returns:

A prepared statement for inserting a ModelObject object into a database.

Throws:

java.sql.SQLException - Thrown if an SQL exception occurs.

fromDatabase

public ModelObject fromDatabase(java.sql.Connection connection,
                                Model model,
                                int modelID,
                                int objectID)
                         throws java.sql.SQLException

Returns a model object from the specified database table.

Specified by:

fromDatabase in interface ModelObject

Parameters:

connection - Database connection.

model - Model built from database.

modelID - Model ID.

objectID - Object ID in associated ModelObjects table.

Returns:

ModelObject corresponding to the specified db connection, model ID and obect ID. A null value is returned if no match found.

Throws:

java.sql.SQLException - Thrown if an SQL exception occurs.

getNodeType

public java.lang.String getNodeType()

Returns the string equivalent of the generic type of the node object; eg "ModelDouble" in GraphTreeNode. If the node object is null then a new non-null empty string is returned.

Returns:

The type (as a string) of the node object.

toXMLNode

public org.w3c.dom.Element toXMLNode(org.w3c.dom.Document document,
                                     org.w3c.dom.Element documentRootNode)
                              throws InvalidObjectException

Returns the xml node of this object.

Specified by:

toXMLNode in interface ModelObject

Parameters:

document - XML document.

documentRootNode - Document root node; ie Model node.

Returns:

The xml node of this object.

Throws:

InvalidObjectException - Thrown if this object's ID is equal to the default ID of -1.

fromXMLNode

public ModelObject fromXMLNode(org.w3c.dom.Document document,
                               org.w3c.dom.Node documentRootNode,
                               org.w3c.dom.Node node,
                               Model model)
                        throws InvalidObjectException

Returns a model object from the specified xml node.

Specified by:

fromXMLNode in interface ModelObject

Parameters:

document - XML document.

documentRootNode - Document root node; ie Model node.

node - XML node.

model - Model to which node object is added.

Returns:

ModelObject corresponding to the specified node. A null value is returned if an error occurred building the object.

Throws:

InvalidObjectException - Thrown if an error occurred building the object.

toX3DNode

public X3DNode toX3DNode(X3DObject x3dObject)
                  throws InvalidObjectException

X3D support. Returns null since no X3D equivalent.

Specified by:

toX3DNode in interface ModelObject

Parameters:

x3dObject - X3D object.

Returns:

X3D object or null if object has no visualisation.

Throws:

InvalidObjectException - Thrown if this object is invalid.