prajna.util

Class AbstractGraph<N,E>

java.lang.Object

prajna.util.AbstractGraph<N,E>

Type Parameters:

N - The class representing the nodes of the graph

E - The class representing the edges of the graph

All Implemented Interfaces:

java.io.Serializable, Graph<N,E>

Direct Known Subclasses:

ClusterGraph, DirectedGraph, UndirectedGraph

public abstract class AbstractGraph<N,E>
extends java.lang.Object
implements Graph<N,E>, java.io.Serializable

Abstract implementation of a Graph. This class provides a number of utility methods for graphs

Author:

Edward Swing

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface prajna.util.Graph

Graph.Segment<N,E>

Constructor Summary

Constructors

Constructor and Description
AbstractGraph()

Method Summary

Methods

Modifier and Type	Method and Description
void	addAll(Graph<? extends N,? extends E> graph) Add all elements from the specified graph to this graph.
void	clear() Clear all nodes and edges from this graph
boolean	contains(java.lang.Object obj) Determines whether the given object is a node within this graph.
boolean	containsEdge(java.lang.Object obj) Determines whether the given object is an edge within this graph.
java.util.Iterator<E>	edgeIterator() Return an iterator over the set of edges for this graph.
boolean	equals(java.lang.Object obj) Determine whether another object is the same as this graph.
java.util.Set<E>	getNodeEdges(N node) Get the set of edges which connect to a particular node.
int	hashCode() Get the hash code for this graph
abstract boolean	isDirected() Return whether this graph is a directed graph
boolean	isEmpty() Return whether the graph is empty.
java.util.Iterator<N>	iterator() Return an iterator over the set of nodes for this graph.
int	order() Return the order of the graph.
boolean	remove(java.lang.Object obj) Remove an object from the graph.
boolean	removeEdge(java.lang.Object edge) Remove the edge from the graph
int	size() Return the size of the graph.

Methods inherited from class java.lang.Object

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

Methods inherited from interface prajna.util.Graph

add, addEdge, getEdge, getEdgeSegment, getEdgeSet, getNodeSet, getSegmentSet

Constructor Detail

AbstractGraph

public AbstractGraph()

Method Detail

addAll

public void addAll(Graph<? extends N,? extends E> graph)

Add all elements from the specified graph to this graph.

Specified by:

addAll in interface Graph<N,E>

Parameters:

graph - the graph to add

clear

public void clear()

Clear all nodes and edges from this graph

Specified by:

clear in interface Graph<N,E>

contains

public boolean contains(java.lang.Object obj)

Determines whether the given object is a node within this graph.

Specified by:

contains in interface Graph<N,E>

Parameters:

obj - the object to test

Returns:

true if the object is a node of this graph, false otherwise

containsEdge

public boolean containsEdge(java.lang.Object obj)

Determines whether the given object is an edge within this graph.

Specified by:

containsEdge in interface Graph<N,E>

Parameters:

obj - the object to test

Returns:

true if the object is an edge of this graph, false otherwise

edgeIterator

public java.util.Iterator<E> edgeIterator()

Return an iterator over the set of edges for this graph. This method calls getEdgeSet and returns the iterator so that the iteration order is consistent.

Specified by:

edgeIterator in interface Graph<N,E>

Returns:

an iterator over the set of edges.

equals

public boolean equals(java.lang.Object obj)

Determine whether another object is the same as this graph. This method returns true if the object compared is a graph, and contains the same nodes and edges as this graph.

Specified by:

equals in interface Graph<N,E>

Overrides:

equals in class java.lang.Object

Parameters:

obj - the object to test

Returns:

true if the object is a graph with the same elements as this graph.

getNodeEdges

public java.util.Set<E> getNodeEdges(N node)

Get the set of edges which connect to a particular node. This includes all edges connecting to the node, regardless of directionality.

Specified by:

getNodeEdges in interface Graph<N,E>

Parameters:

node - the node to check

Returns:

the set of edges connecting to the node

hashCode

public int hashCode()

Get the hash code for this graph

Specified by:

hashCode in interface Graph<N,E>

Overrides:

hashCode in class java.lang.Object

Returns:

the hash code

isDirected

public abstract boolean isDirected()

Return whether this graph is a directed graph

Specified by:

isDirected in interface Graph<N,E>

Returns:

true if the graph is directed, false if it is undirected.

isEmpty

public boolean isEmpty()

Return whether the graph is empty. The graph is empty if it has no nodes.

Specified by:

isEmpty in interface Graph<N,E>

Returns:

true if the graph is empty, false otherwise

iterator

public java.util.Iterator<N> iterator()

Return an iterator over the set of nodes for this graph.

Specified by:

iterator in interface Graph<N,E>

Returns:

an iterator over the set of nodes.

order

public int order()

Return the order of the graph. The order of the graph is the number of nodes in the graph

Specified by:

order in interface Graph<N,E>

Returns:

the graph order

remove

public boolean remove(java.lang.Object obj)

Remove an object from the graph. This removes the object from the node set, and removes any incident edges as well.

Specified by:

remove in interface Graph<N,E>

Parameters:

obj - the object to remove

Returns:

true if the graph was changed as a result of this operation

removeEdge

public boolean removeEdge(java.lang.Object edge)

Remove the edge from the graph

Specified by:

removeEdge in interface Graph<N,E>

Parameters:

edge - the edge to remove

Returns:

true if the graph was changed as a result of this operation

size

public int size()

Return the size of the graph. The size of the graph is the number of edges in the graph

Specified by:

size in interface Graph<N,E>

Returns:

the graph size