Class EdgeReversedGraph<V,E>
 java.lang.Object

 org.jgrapht.graph.AbstractGraph<V,E>

 org.jgrapht.graph.GraphDelegator<V,E>

 org.jgrapht.graph.EdgeReversedGraph<V,E>

 Type Parameters:
V
 the graph vertex typeE
 the graph edge type
 All Implemented Interfaces:
Serializable
,Graph<V,E>
public class EdgeReversedGraph<V,E> extends GraphDelegator<V,E> implements Graph<V,E>
Provides an edgereversed view $g'$ of a directed graph $g$. The vertex sets for the two graphs are the same, but g' contains an edge $(v2, v1)$ iff g$$ contains an edge $(v1, v2)$. $g'$ is backed by $g$, so changes to $g$ are reflected in $g'$, and vice versa.This class allows you to use a directed graph algorithm in reverse. For example, suppose you have a directed graph representing a tree, with edges from parent to child, and you want to find all of the parents of a node. To do this, simply create an edgereversed graph and pass that as input to
DepthFirstIterator
. Author:
 John V. Sichi
 See Also:
AsUndirectedGraph
, Serialized Form


Field Summary

Fields inherited from interface org.jgrapht.Graph
DEFAULT_EDGE_WEIGHT


Constructor Summary
Constructors Constructor Description EdgeReversedGraph(Graph<V,E> g)
Creates a new EdgeReversedGraph.

Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description E
addEdge(V sourceVertex, V targetVertex)
Creates a new edge in this graph, going from the source vertex to the target vertex, and returns the created edge.boolean
addEdge(V sourceVertex, V targetVertex, E e)
Adds the specified edge to this graph, going from the source vertex to the target vertex.Set<E>
getAllEdges(V sourceVertex, V targetVertex)
Returns a set of all edges connecting source vertex to target vertex if such vertices exist in this graph.E
getEdge(V sourceVertex, V targetVertex)
Returns an edge connecting source vertex to target vertex if such vertices and such edge exist in this graph.V
getEdgeSource(E e)
Returns the source vertex of an edge.V
getEdgeTarget(E e)
Returns the target vertex of an edge.Set<E>
incomingEdgesOf(V vertex)
Returns a set of all edges incoming into the specified vertex.int
inDegreeOf(V vertex)
Returns the "in degree" of the specified vertex.int
outDegreeOf(V vertex)
Returns the "out degree" of the specified vertex.Set<E>
outgoingEdgesOf(V vertex)
Returns a set of all edges outgoing from the specified vertex.E
removeEdge(V sourceVertex, V targetVertex)
Removes an edge going from source vertex to target vertex, if such vertices and such edge exist in this graph.String
toString()
Returns a string of the parenthesized pair (V, E) representing this G=(V,E) graph.
Methods inherited from class org.jgrapht.graph.GraphDelegator
addVertex, addVertex, containsEdge, containsVertex, degreeOf, edgeSet, edgesOf, getDelegate, getEdgeSupplier, getEdgeWeight, getType, getVertexSupplier, removeEdge, removeVertex, setEdgeWeight, vertexSet

Methods inherited from class org.jgrapht.graph.AbstractGraph
assertVertexExist, containsEdge, equals, hashCode, removeAllEdges, removeAllEdges, removeAllEdges, removeAllVertices, toStringFromSets

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.jgrapht.Graph
addVertex, addVertex, containsEdge, containsEdge, containsVertex, degreeOf, edgeSet, edgesOf, getEdgeSupplier, getEdgeWeight, getType, getVertexSupplier, removeAllEdges, removeAllEdges, removeAllVertices, removeEdge, removeVertex, setEdgeWeight, setEdgeWeight, vertexSet




Method Detail

getEdge
public E getEdge(V sourceVertex, V targetVertex)
Description copied from class:GraphDelegator
Returns an edge connecting source vertex to target vertex if such vertices and such edge exist in this graph. Otherwise returnsnull
. If any of the specified vertices isnull
returnsnull
In undirected graphs, the returned edge may have its source and target vertices in the opposite order.
 Specified by:
getEdge
in interfaceGraph<V,E>
 Overrides:
getEdge
in classGraphDelegator<V,E>
 Parameters:
sourceVertex
 source vertex of the edge.targetVertex
 target vertex of the edge. Returns:
 an edge connecting source vertex to target vertex.
 See Also:
Graph.getEdge(Object, Object)

getAllEdges
public Set<E> getAllEdges(V sourceVertex, V targetVertex)
Description copied from class:GraphDelegator
Returns a set of all edges connecting source vertex to target vertex if such vertices exist in this graph. If any of the vertices does not exist or isnull
, returnsnull
. If both vertices exist but no edges found, returns an empty set.In undirected graphs, some of the returned edges may have their source and target vertices in the opposite order. In simple graphs the returned set is either singleton set or empty set.
 Specified by:
getAllEdges
in interfaceGraph<V,E>
 Overrides:
getAllEdges
in classGraphDelegator<V,E>
 Parameters:
sourceVertex
 source vertex of the edge.targetVertex
 target vertex of the edge. Returns:
 a set of all edges connecting source vertex to target vertex.
 See Also:
Graph.getAllEdges(Object, Object)

addEdge
public E addEdge(V sourceVertex, V targetVertex)
Description copied from class:GraphDelegator
Creates a new edge in this graph, going from the source vertex to the target vertex, and returns the created edge. Some graphs do not allow edgemultiplicity. In such cases, if the graph already contains an edge from the specified source to the specified target, than this method does not change the graph and returnsnull
.The source and target vertices must already be contained in this graph. If they are not found in graph
IllegalArgumentException
is thrown.This method creates the new edge
e
using this graph's edge supplier (seeGraph.getEdgeSupplier()
). For the new edge to be addede
must not be equal to any other edge the graph (even if the graph allows edgemultiplicity). More formally, the graph must not contain any edgee2
such thate2.equals(e)
. If suche2
is found then the newly created edgee
is abandoned, the method leaves this graph unchanged and returnsnull
.If the underlying graph implementation's
Graph.getEdgeSupplier()
returnsnull
, then this method cannot create edges and throws anUnsupportedOperationException
. Specified by:
addEdge
in interfaceGraph<V,E>
 Overrides:
addEdge
in classGraphDelegator<V,E>
 Parameters:
sourceVertex
 source vertex of the edge.targetVertex
 target vertex of the edge. Returns:
 The newly created edge if added to the graph, otherwise
null
.  See Also:
Graph.addEdge(Object, Object)

addEdge
public boolean addEdge(V sourceVertex, V targetVertex, E e)
Description copied from class:GraphDelegator
Adds the specified edge to this graph, going from the source vertex to the target vertex. More formally, adds the specified edge,e
, to this graph if this graph contains no edgee2
such thate2.equals(e)
. If this graph already contains such an edge, the call leaves this graph unchanged and returnsfalse
. Some graphs do not allow edgemultiplicity. In such cases, if the graph already contains an edge from the specified source to the specified target, than this method does not change the graph and returnsfalse
. If the edge was added to the graph, returnstrue
.The source and target vertices must already be contained in this graph. If they are not found in graph IllegalArgumentException is thrown.
 Specified by:
addEdge
in interfaceGraph<V,E>
 Overrides:
addEdge
in classGraphDelegator<V,E>
 Parameters:
sourceVertex
 source vertex of the edge.targetVertex
 target vertex of the edge.e
 edge to be added to this graph. Returns:
true
if this graph did not already contain the specified edge. See Also:
Graph.addEdge(Object, Object, Object)

inDegreeOf
public int inDegreeOf(V vertex)
Description copied from class:GraphDelegator
Returns the "in degree" of the specified vertex.The "in degree" of a vertex in a directed graph is the number of inward directed edges from that vertex. See http://mathworld.wolfram.com/Indegree.html.
In the case of undirected graphs this method returns the number of edges touching the vertex. Edges with same source and target vertices (selfloops) are counted twice.
 Specified by:
inDegreeOf
in interfaceGraph<V,E>
 Overrides:
inDegreeOf
in classGraphDelegator<V,E>
 Parameters:
vertex
 vertex whose degree is to be calculated. Returns:
 the degree of the specified vertex.
 See Also:
Graph.inDegreeOf(Object)

outDegreeOf
public int outDegreeOf(V vertex)
Description copied from class:GraphDelegator
Returns the "out degree" of the specified vertex.The "out degree" of a vertex in a directed graph is the number of outward directed edges from that vertex. See http://mathworld.wolfram.com/Outdegree.html.
In the case of undirected graphs this method returns the number of edges touching the vertex. Edges with same source and target vertices (selfloops) are counted twice.
 Specified by:
outDegreeOf
in interfaceGraph<V,E>
 Overrides:
outDegreeOf
in classGraphDelegator<V,E>
 Parameters:
vertex
 vertex whose degree is to be calculated. Returns:
 the degree of the specified vertex.
 See Also:
Graph.outDegreeOf(Object)

incomingEdgesOf
public Set<E> incomingEdgesOf(V vertex)
Description copied from class:GraphDelegator
Returns a set of all edges incoming into the specified vertex.In the case of undirected graphs this method returns all edges touching the vertex, thus, some of the returned edges may have their source and target vertices in the opposite order.
 Specified by:
incomingEdgesOf
in interfaceGraph<V,E>
 Overrides:
incomingEdgesOf
in classGraphDelegator<V,E>
 Parameters:
vertex
 the vertex for which the list of incoming edges to be returned. Returns:
 a set of all edges incoming into the specified vertex.
 See Also:
Graph.incomingEdgesOf(Object)

outgoingEdgesOf
public Set<E> outgoingEdgesOf(V vertex)
Description copied from class:GraphDelegator
Returns a set of all edges outgoing from the specified vertex.In the case of undirected graphs this method returns all edges touching the vertex, thus, some of the returned edges may have their source and target vertices in the opposite order.
 Specified by:
outgoingEdgesOf
in interfaceGraph<V,E>
 Overrides:
outgoingEdgesOf
in classGraphDelegator<V,E>
 Parameters:
vertex
 the vertex for which the list of outgoing edges to be returned. Returns:
 a set of all edges outgoing from the specified vertex.
 See Also:
Graph.outgoingEdgesOf(Object)

removeEdge
public E removeEdge(V sourceVertex, V targetVertex)
Description copied from class:GraphDelegator
Removes an edge going from source vertex to target vertex, if such vertices and such edge exist in this graph. Returns the edge if removed ornull
otherwise. Specified by:
removeEdge
in interfaceGraph<V,E>
 Overrides:
removeEdge
in classGraphDelegator<V,E>
 Parameters:
sourceVertex
 source vertex of the edge.targetVertex
 target vertex of the edge. Returns:
 The removed edge, or
null
if no edge removed.  See Also:
Graph.removeEdge(Object, Object)

getEdgeSource
public V getEdgeSource(E e)
Description copied from class:GraphDelegator
Returns the source vertex of an edge. For an undirected graph, source and target are distinguishable designations (but without any mathematical meaning). Specified by:
getEdgeSource
in interfaceGraph<V,E>
 Overrides:
getEdgeSource
in classGraphDelegator<V,E>
 Parameters:
e
 edge of interest Returns:
 source vertex
 See Also:
Graph.getEdgeSource(Object)

getEdgeTarget
public V getEdgeTarget(E e)
Description copied from class:GraphDelegator
Returns the target vertex of an edge. For an undirected graph, source and target are distinguishable designations (but without any mathematical meaning). Specified by:
getEdgeTarget
in interfaceGraph<V,E>
 Overrides:
getEdgeTarget
in classGraphDelegator<V,E>
 Parameters:
e
 edge of interest Returns:
 target vertex
 See Also:
Graph.getEdgeTarget(Object)

toString
public String toString()
Description copied from class:GraphDelegator
Returns a string of the parenthesized pair (V, E) representing this G=(V,E) graph. 'V' is the string representation of the vertex set, and 'E' is the string representation of the edge set. Overrides:
toString
in classGraphDelegator<V,E>
 Returns:
 a string representation of this graph.
 See Also:
Object.toString()

