org.girod.jgraphml.model

Class AbstractGraphMLDiagram

java.lang.Object

edu.uci.ics.jung.graph.AbstractGraph<IGraphMLNode,GraphMLEdge>

org.girod.jgraphml.model.AbstractGraphMLDiagram

All Implemented Interfaces:

Graph<IGraphMLNode,GraphMLEdge>, Hypergraph<IGraphMLNode,GraphMLEdge>, java.io.Serializable, java.lang.Cloneable, NodeParent

Direct Known Subclasses:

GraphMLDiagram

public abstract class AbstractGraphMLDiagram
extends AbstractGraph<IGraphMLNode,GraphMLEdge>
implements NodeParent, java.lang.Cloneable

An abstract graphml diagram.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.SortedMap<java.lang.String,IGraphMLNode>	children The children nodes.
protected EdgeType	defaultEdgeType The diagram edges type.
protected DiagramDefaults	defaults The diagram defaults.
protected java.util.SortedMap<java.lang.String,GraphMLEdge>	edges The edges.
protected java.util.SortedMap<java.lang.String,GraphMLGroupNode>	groupNodes The node groups.
protected java.util.SortedMap<java.lang.String,IGraphMLNode>	nodes The nodes.

Constructor Summary

Constructors

Constructor and Description
AbstractGraphMLDiagram()
AbstractGraphMLDiagram(DiagramDefaults defaults)

Method Summary

Modifier and Type	Method and Description
boolean	addChild(IGraphMLNode node) Adds a node to this graph.
boolean	addEdge(GraphMLEdge edge, IGraphMLNode source, IGraphMLNode target) Add an edge from a source to a target.
GraphMLEdge	addEdge(IGraphMLNode source, IGraphMLNode target) Add an edge from a source to a target.
GraphMLEdge	addEdgeFromTemplate(IGraphMLNode source, IGraphMLNode target, java.lang.String id) Add an edge from a source to a target, using a template.
boolean	addEdgeWithEndpoints(GraphMLEdge edge, Pair<? extends IGraphMLNode> endpoints, EdgeType edgeType) Add an edgeto this graph with the specified endpoints and EdgeType.
GraphMLGroupNode	addGroupNode() Add a group node with an id specified automatically.
GraphMLGroupNode	addGroupNode(java.lang.String id) Add a group node with a specified id.
GraphMLGroupNode	addGroupNodeFromTemplate(java.lang.String id) Add a group node, using a template.
GraphMLNode	addNode() Add a node with an id specified automatically.
boolean	addNode(IGraphMLNode node) Adds a node to this graph.
boolean	addNode(IGraphMLNode node, boolean acceptNewID) Adds a node to this graph.
GraphMLNode	addNode(java.lang.String id) Add a node with a specified id.
GraphMLNode	addNodeFromTemplate(java.lang.String id) Add a node, using a template.
boolean	addVertex(IGraphMLNode vertex) Adds vertex to this graph.
boolean	addVertex(IGraphMLNode vertex, boolean acceptNewID) Adds vertex to this graph.
AbstractGraphMLDiagram	clone()
boolean	containsEdge(GraphMLEdge edge) Returns true if this graph's edge collection contains edge.
boolean	containsVertex(IGraphMLNode vertex) Returns true if this graph's vertex collection contains vertex.
int	countEdges() Return the number of edges.
int	countGroupNodes() Return the number of group nodes.
int	countNodes() Return the number of nodes.
void	detachNode(AbstractGraphMLNode node) Detach a node from the diagram.
java.util.SortedMap<java.lang.String,IGraphMLNode>	getChildren() Return the nodes.
EdgeType	getDefaultEdgeType() Returns the default edge type for this graph.
DiagramDefaults	getDefaults() Return the diagram defaults.
IGraphMLNode	getDest(GraphMLEdge edge) If directed_edge is a directed edge in this graph, returns the destination; otherwise returns null.
AbstractGraphMLDiagram	getDiagram() Return this diagram.
int	getEdgeCount() Returns the number of edges in this graph.
int	getEdgeCount(EdgeType edgeType) Returns the number of edges in this graph.
java.util.SortedMap<java.lang.String,GraphMLEdge>	getEdges() Return the edges.
java.util.Collection<GraphMLEdge>	getEdges(EdgeType edgeType) Returns the collection of edges in this graph which are of type edgeType.
java.util.Collection<GraphMLEdge>	getEdgesView() Returns a view of all edges in this graph.
EdgeType	getEdgeType(GraphMLEdge edge) Returns the edge type of edge in this graph.
Pair<IGraphMLNode>	getEndpoints(GraphMLEdge edge) Returns the endpoints of edge as a Pair<V>.
java.util.SortedMap<java.lang.String,GraphMLGroupNode>	getGroupNodes() Return the group nodes.
java.util.Collection<GraphMLEdge>	getIncidentEdges(IGraphMLNode vertex) Returns the collection of edges in this graph which are connected to vertex.
java.util.Collection<GraphMLEdge>	getInEdges(IGraphMLNode vertex) Returns a Collection view of the incoming edges incident to vertex in this graph.
java.util.Collection<IGraphMLNode>	getNeighbors(IGraphMLNode vertex) Returns the collection of vertices which are connected to vertex via any edges in this graph.
java.util.SortedMap<java.lang.String,IGraphMLNode>	getNodes() Return the nodes.
java.util.Collection<GraphMLEdge>	getOutEdges(IGraphMLNode vertex) Returns a Collection view of the outgoing edges incident to vertex in this graph.
java.util.Collection<IGraphMLNode>	getPredecessors(IGraphMLNode vertex) Returns a Collection view of the predecessors of vertex in this graph.
IGraphMLNode	getSource(GraphMLEdge edge) If directed_edge is a directed edge in this graph, returns the source; otherwise returns null.
java.util.Collection<IGraphMLNode>	getSuccessors(IGraphMLNode vertex) Returns a Collection view of the successors of vertex in this graph.
protected java.lang.String	getUnusedNodeID(java.lang.String id) Return an unused id for nodes.
int	getVertexCount() Returns the number of vertices in this graph.
java.util.Collection<IGraphMLNode>	getVerticesView() Returns a view of all vertices in this graph.
boolean	hasGroupNodes() Return true if there are group nodes.
boolean	isDest(IGraphMLNode vertex, GraphMLEdge edge) Returns true if vertex is the destination of edge.
boolean	isSource(IGraphMLNode vertex, GraphMLEdge edge) Returns true if vertex is the source of edge.
boolean	removeEdge(GraphMLEdge edge) Removes edge from this graph.
boolean	removeVertex(IGraphMLNode vertex) Removes vertex from this graph.
void	setDefaultEdgeType(EdgeType edgeType) Set the default edge type for this graph.
void	setDefaults(DiagramDefaults defaults) Set the diagram defaults.

Methods inherited from class edu.uci.ics.jung.graph.AbstractGraph

addEdge, addEdgeWithEndPoints, addEdgeWithVertices, addEdgeWithVertices, degree, findEdge, findEdgeSet, getIncidentCount, getIncidentVertices, getNeighborCount, getOpposite, getPredecessorCount, getSuccessorCount, getValidatedEndpoints, inDegree, isIncident, isNeighbor, isPredecessor, isSuccessor, outDegree

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.girod.jgraphml.model.NodeParent

addGroupNodeFromTemplateWithLabel, addGroupNodeWithLabel, addNodeFromTemplateWithLabel, addNodeWithLabel

Field Detail

groupNodes

protected java.util.SortedMap<java.lang.String,GraphMLGroupNode> groupNodes

The node groups.

nodes

protected java.util.SortedMap<java.lang.String,IGraphMLNode> nodes

The nodes.

children

protected java.util.SortedMap<java.lang.String,IGraphMLNode> children

The children nodes.

edges

protected java.util.SortedMap<java.lang.String,GraphMLEdge> edges

The edges.

defaultEdgeType

protected EdgeType defaultEdgeType

The diagram edges type.

defaults

protected DiagramDefaults defaults

The diagram defaults.

Constructor Detail

AbstractGraphMLDiagram

public AbstractGraphMLDiagram()

AbstractGraphMLDiagram

public AbstractGraphMLDiagram(DiagramDefaults defaults)

Method Detail

setDefaults

public void setDefaults(DiagramDefaults defaults)

Set the diagram defaults.

Parameters:

defaults - the diagram defaults.

getDefaults

public DiagramDefaults getDefaults()

Return the diagram defaults.

Returns:

the diagram defaults.

countNodes

public int countNodes()

Return the number of nodes.

Specified by:

countNodes in interface NodeParent

Returns:

the number of nodes

countGroupNodes

public int countGroupNodes()

Return the number of group nodes.

Specified by:

countGroupNodes in interface NodeParent

Returns:

the number of group nodes

hasGroupNodes

public boolean hasGroupNodes()

Return true if there are group nodes.

Specified by:

hasGroupNodes in interface NodeParent

Returns:

true if there are group nodes

getDiagram

public AbstractGraphMLDiagram getDiagram()

Return this diagram.

Specified by:

getDiagram in interface NodeParent

Returns:

this diagram

countEdges

public int countEdges()

Return the number of edges.

Returns:

the number of edges

detachNode

public void detachNode(AbstractGraphMLNode node)

Detach a node from the diagram.

Parameters:

node - the node

clone

public AbstractGraphMLDiagram clone()

Overrides:

clone in class java.lang.Object

addEdgeWithEndpoints

public boolean addEdgeWithEndpoints(GraphMLEdge edge,
                                    Pair<? extends IGraphMLNode> endpoints,
                                    EdgeType edgeType)

Add an edgeto this graph with the specified endpoints and EdgeType.

Specified by:

addEdgeWithEndpoints in class AbstractGraph<IGraphMLNode,GraphMLEdge>

Parameters:

edge - the edge

endpoints - the endPoints

edgeType - the edge type

Returns:

true if the graph was modified as a result of this call

getEndpoints

public Pair<IGraphMLNode> getEndpoints(GraphMLEdge edge)

Returns the endpoints of edge as a Pair<V>.

Specified by:

getEndpoints in interface Graph<IGraphMLNode,GraphMLEdge>

Parameters:

edge - the edge whose endpoints are to be returned

Returns:

the endpoints (incident vertices) of edge

isDest

public boolean isDest(IGraphMLNode vertex,
                      GraphMLEdge edge)

Returns true if vertex is the destination of edge. Equivalent to getDest(edge).equals(vertex).

Specified by:

isDest in interface Graph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex to be queried

edge - the edge to be queried

Returns:

true iff vertex is the destination of edge

isSource

public boolean isSource(IGraphMLNode vertex,
                        GraphMLEdge edge)

Returns true if vertex is the source of edge. Equivalent to getSource(edge).equals(vertex).

Specified by:

isSource in interface Graph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex to be queried

edge - the edge to be queried

Returns:

true iff vertex is the source of edge

getDest

public IGraphMLNode getDest(GraphMLEdge edge)

If directed_edge is a directed edge in this graph, returns the destination; otherwise returns null. The destination of a directed edge d is defined to be the vertex incident to d for which d is an incoming edge. directed_edge is guaranteed to be a directed edge if its EdgeType is DIRECTED.

Specified by:

getDest in interface Graph<IGraphMLNode,GraphMLEdge>

Specified by:

getDest in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

edge -

Returns:

the destination of directed_edge if it is a directed edge in this graph, or null otherwise

getSource

public IGraphMLNode getSource(GraphMLEdge edge)

If directed_edge is a directed edge in this graph, returns the source; otherwise returns null. The source of a directed edge d is defined to be the vertex for which d is an outgoing edge. directed_edge is guaranteed to be a directed edge if its EdgeType is DIRECTED.

Specified by:

getSource in interface Graph<IGraphMLNode,GraphMLEdge>

Specified by:

getSource in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

edge -

Returns:

the source of directed_edge if it is a directed edge in this graph, or null otherwise

getSuccessors

public java.util.Collection<IGraphMLNode> getSuccessors(IGraphMLNode vertex)

Returns a Collection view of the successors of vertex in this graph. A successor of vertex is defined as a vertex v which is connected to vertex by an edge e, where e is an incoming edge of v and an outgoing edge of vertex.

Specified by:

getSuccessors in interface Graph<IGraphMLNode,GraphMLEdge>

Specified by:

getSuccessors in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex whose predecessors are to be returned

Returns:

a Collection view of the successors of vertex in this graph

getPredecessors

public java.util.Collection<IGraphMLNode> getPredecessors(IGraphMLNode vertex)

Returns a Collection view of the predecessors of vertex in this graph. A predecessor of vertex is defined as a vertex v which is connected to vertex by an edge e, where e is an outgoing edge of v and an incoming edge of vertex.

Specified by:

getPredecessors in interface Graph<IGraphMLNode,GraphMLEdge>

Specified by:

getPredecessors in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex whose predecessors are to be returned

Returns:

a Collection view of the predecessors of vertex in this graph

getInEdges

public java.util.Collection<GraphMLEdge> getInEdges(IGraphMLNode vertex)

Returns a Collection view of the incoming edges incident to vertex in this graph.

Specified by:

getInEdges in interface Graph<IGraphMLNode,GraphMLEdge>

Specified by:

getInEdges in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex whose incoming edges are to be returned

Returns:

a Collection view of the incoming edges incident to vertex in this graph

getOutEdges

public java.util.Collection<GraphMLEdge> getOutEdges(IGraphMLNode vertex)

Returns a Collection view of the outgoing edges incident to vertex in this graph.

Specified by:

getOutEdges in interface Graph<IGraphMLNode,GraphMLEdge>

Specified by:

getOutEdges in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex whose outgoing edges are to be returned

Returns:

a Collection view of the outgoing edges incident to vertex in this graph

getEdgeCount

public int getEdgeCount()

Returns the number of edges in this graph.

Specified by:

getEdgeCount in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Returns:

the number of edges in this graph

getEdgeCount

public int getEdgeCount(EdgeType edgeType)

Returns the number of edges in this graph.

Specified by:

getEdgeCount in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

edgeType - the edge type

Returns:

the number of edges in this graph

getEdges

public java.util.Collection<GraphMLEdge> getEdges(EdgeType edgeType)

Returns the collection of edges in this graph which are of type edgeType.

Specified by:

getEdges in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

edgeType - the type of edges to be returned

Returns:

the collection of edges which are of type edge_type, or null if the graph does not accept edges of this type

See Also:

EdgeType

setDefaultEdgeType

public void setDefaultEdgeType(EdgeType edgeType)

Set the default edge type for this graph.

Parameters:

edgeType - the default edge type for this graph

getDefaultEdgeType

public EdgeType getDefaultEdgeType()

Returns the default edge type for this graph.

Specified by:

getDefaultEdgeType in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Returns:

the default edge type for this graph

getEdgeType

public EdgeType getEdgeType(GraphMLEdge edge)

Returns the edge type of edge in this graph.

Specified by:

getEdgeType in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

edge -

Returns:

the EdgeType of edge, or null if edge has no defined type

removeEdge

public boolean removeEdge(GraphMLEdge edge)

Removes edge from this graph. Fails if edge is null, or is otherwise not an element of this graph.

Specified by:

removeEdge in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

edge - the edge to remove

Returns:

true if the removal is successful, false otherwise

removeVertex

public boolean removeVertex(IGraphMLNode vertex)

Removes vertex from this graph. As a side effect, removes any edges e incident to vertex if the removal of vertex would cause e to be incident to an illegal number of vertices. (Thus, for example, incident hyperedges are not removed, but incident edges--which must be connected to a vertex at both endpoints--are removed.) Fails under the following circumstances:

• vertex is not an element of this graph
• vertex is null

Specified by:

removeVertex in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex to remove

Returns:

true if the removal is successful, false otherwise

addVertex

public boolean addVertex(IGraphMLNode vertex)

Adds vertex to this graph. Fails if vertex is null or already in the graph.

Specified by:

addVertex in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex to add

Returns:

true if the add is successful, and false otherwise

Throws:

java.lang.IllegalArgumentException - if vertex is null

addNode

public boolean addNode(IGraphMLNode node)

Adds a node to this graph. Defer to addVertex(org.girod.jgraphml.model.IGraphMLNode).

Parameters:

node - the vertex to add

Returns:

true if the add is successful, and false otherwise

Throws:

java.lang.IllegalArgumentException - if vertex is null

addChild

public boolean addChild(IGraphMLNode node)

Adds a node to this graph. Defer to addVertex(org.girod.jgraphml.model.IGraphMLNode).

Specified by:

addChild in interface NodeParent

Parameters:

node - the node to add

Returns:

true if the add is successful, and false otherwise

Throws:

java.lang.IllegalArgumentException - if node is null

addNode

public boolean addNode(IGraphMLNode node,
                       boolean acceptNewID)

Adds a node to this graph. Defer to addVertex(org.girod.jgraphml.model.IGraphMLNode, boolean).

Parameters:

node - the vertex to add

acceptNewID - if true, accept to rename the vertex / node if the ID aleady exists

Returns:

true if the add is successful, and false otherwise

Throws:

java.lang.IllegalArgumentException - if vertex is null

addNode

public GraphMLNode addNode(java.lang.String id)

Add a node with a specified id.

Specified by:

addNode in interface NodeParent

Parameters:

id - the node id

Returns:

the node

addGroupNode

public GraphMLGroupNode addGroupNode(java.lang.String id)

Add a group node with a specified id.

Specified by:

addGroupNode in interface NodeParent

Parameters:

id - the group node id

Returns:

the node

addNode

public GraphMLNode addNode()

Add a node with an id specified automatically.

Specified by:

addNode in interface NodeParent

Returns:

the node

addNodeFromTemplate

public GraphMLNode addNodeFromTemplate(java.lang.String id)
                                throws TemplateAccessException

Add a node, using a template.

Specified by:

addNodeFromTemplate in interface NodeParent

Parameters:

id - the template id

Returns:

the node

Throws:

TemplateAccessException

addGroupNode

public GraphMLGroupNode addGroupNode()

Add a group node with an id specified automatically.

Specified by:

addGroupNode in interface NodeParent

Returns:

the group node

addGroupNodeFromTemplate

public GraphMLGroupNode addGroupNodeFromTemplate(java.lang.String id)
                                          throws TemplateAccessException

Add a group node, using a template.

Specified by:

addGroupNodeFromTemplate in interface NodeParent

Parameters:

id - the template id

Returns:

the group node

Throws:

TemplateAccessException

getNodes

public java.util.SortedMap<java.lang.String,IGraphMLNode> getNodes()

Return the nodes.

Returns:

the nodes

getChildren

public java.util.SortedMap<java.lang.String,IGraphMLNode> getChildren()

Return the nodes.

Specified by:

getChildren in interface NodeParent

Returns:

the nodes

getGroupNodes

public java.util.SortedMap<java.lang.String,GraphMLGroupNode> getGroupNodes()

Return the group nodes.

Specified by:

getGroupNodes in interface NodeParent

Returns:

the group nodes

getEdges

public java.util.SortedMap<java.lang.String,GraphMLEdge> getEdges()

Return the edges.

Returns:

the edges

addVertex

public boolean addVertex(IGraphMLNode vertex,
                         boolean acceptNewID)
                  throws TemplateAccessException

Adds vertex to this graph. Fails if vertex is null or already in the graph. Accept to rename the vertex / node depending on the acceptNewID is true.

Parameters:

vertex - the vertex to add

acceptNewID - if true, accept to rename the vertex / node if the ID aleady exists

Returns:

true if the add is successful, and false otherwise

Throws:

java.lang.IllegalArgumentException - if vertex is null

TemplateAccessException

addEdge

public boolean addEdge(GraphMLEdge edge,
                       IGraphMLNode source,
                       IGraphMLNode target)
                throws TemplateAccessException

Add an edge from a source to a target.

Specified by:

addEdge in interface Graph<IGraphMLNode,GraphMLEdge>

Overrides:

addEdge in class AbstractGraph<IGraphMLNode,GraphMLEdge>

Parameters:

edge - the edge

source - the edge source

target - the edge target

Returns:

true if the edge could be added

Throws:

TemplateAccessException

See Also:

Graph.addEdge(Object, Object, Object, EdgeType)

addEdge

public GraphMLEdge addEdge(IGraphMLNode source,
                           IGraphMLNode target)

Add an edge from a source to a target.

Parameters:

source - the edge source

target - the edge target

Returns:

the edge

addEdgeFromTemplate

public GraphMLEdge addEdgeFromTemplate(IGraphMLNode source,
                                       IGraphMLNode target,
                                       java.lang.String id)
                                throws TemplateAccessException

Add an edge from a source to a target, using a template.

Parameters:

source - the edge source

target - the edge target

id - the template id

Returns:

the edge

Throws:

TemplateAccessException

getUnusedNodeID

protected java.lang.String getUnusedNodeID(java.lang.String id)

Return an unused id for nodes.

Parameters:

id - the id

Returns:

the unused id

getIncidentEdges

public java.util.Collection<GraphMLEdge> getIncidentEdges(IGraphMLNode vertex)

Returns the collection of edges in this graph which are connected to vertex.

Specified by:

getIncidentEdges in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex whose incident edges are to be returned

Returns:

the collection of edges which are connected to vertex, or null if vertex is not present

getNeighbors

public java.util.Collection<IGraphMLNode> getNeighbors(IGraphMLNode vertex)

Returns the collection of vertices which are connected to vertex via any edges in this graph. If vertex is connected to itself with a self-loop, then it will be included in the collection returned.

Specified by:

getNeighbors in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex whose neighbors are to be returned

Returns:

the collection of vertices which are connected to vertex, or null if vertex is not present

getVertexCount

public int getVertexCount()

Returns the number of vertices in this graph.

Specified by:

getVertexCount in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Returns:

the number of vertices in this graph

containsEdge

public boolean containsEdge(GraphMLEdge edge)

Returns true if this graph's edge collection contains edge. Equivalent to getEdges().contains(edge).

Specified by:

containsEdge in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

edge - the edge whose presence is being queried

Returns:

true iff this graph contains an edge edge

containsVertex

public boolean containsVertex(IGraphMLNode vertex)

Returns true if this graph's vertex collection contains vertex. Equivalent to getVertices().contains(vertex).

Specified by:

containsVertex in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Parameters:

vertex - the vertex whose presence is being queried

Returns:

true iff this graph contains a vertex vertex

getVerticesView

public java.util.Collection<IGraphMLNode> getVerticesView()

Returns a view of all vertices in this graph. In general, this obeys the Collection contract, and therefore makes no guarantees about the ordering of the vertices within the set.

Specified by:

getVerticesView in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Returns:

a Collection view of all vertices in this graph

getEdgesView

public java.util.Collection<GraphMLEdge> getEdgesView()

Returns a view of all edges in this graph. In general, this obeys the Collection contract, and therefore makes no guarantees about the ordering of the vertices within the set.

Specified by:

getEdgesView in interface Hypergraph<IGraphMLNode,GraphMLEdge>

Returns:

a Collection view of all edges in this graph