V
- the graph vertex typeE
- the graph edge typepublic class SimpleGraphMLImporter<V,E> extends Object implements GraphImporter<V,E>
This is a simple implementation with supports only a limited set of features of the GraphML
specification. For a more rigorous parser use GraphMLImporter
. This version is oriented
towards parsing speed.
The importer uses the graph suppliers (Graph.getVertexSupplier()
and
Graph.getEdgeSupplier()
) in order to create new vertices and edges. Moreover, it notifies
lazily and completely out-of-order for any additional vertex, edge or graph attributes in the
input file. Users can register consumers for vertex, edge and graph attributes after construction
of the importer. Finally, default attribute values are completely ignored.
For a description of the format see http://en.wikipedia.org/wiki/ GraphML or the GraphML Primer.
Below is small example of a graph in GraphML format.
<?xml version="1.0" encoding="UTF-8"?>
<graphml xmlns="http://graphml.graphdrawing.org/xmlns"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://graphml.graphdrawing.org/xmlns
http://graphml.graphdrawing.org/xmlns/1.0/graphml.xsd">
<key id="d0" for="node" attr.name="color" attr.type="string" />
<key id="d1" for="edge" attr.name="weight" attr.type="double"/>
<graph id="G" edgedefault="undirected">
<node id="n0">
<data key="d0">green</data>
</node>
<node id="n1">
<data key="d0">black</data>
</node>
<node id="n2">
<data key="d0">blue</data>
</node>
<node id="n3">
<data key="d0">red</data>
</node>
<node id="n4">
<data key="d0">white</data>
</node>
<node id="n5">
<data key="d0">turquoise</data>
</node>
<edge id="e0" source="n0" target="n2">
<data key="d1">1.0</data>
</edge>
<edge id="e1" source="n0" target="n1">
<data key="d1">1.0</data>
</edge>
<edge id="e2" source="n1" target="n3">
<data key="d1">2.0</data>
</edge>
<edge id="e3" source="n3" target="n2"/>
<edge id="e4" source="n2" target="n4"/>
<edge id="e5" source="n3" target="n5"/>
<edge id="e6" source="n5" target="n4">
<data key="d1">1.1</data>
</edge>
</graph>
</graphml>
The importer reads the input into a graph which is provided by the user. In case the graph is
weighted and the corresponding edge key with attr.name="weight" is defined, the importer also
reads edge weights. Otherwise edge weights are ignored. To test whether the graph is weighted,
method Graph.getType()
can be used.
The provided graph object, where the imported graph will be stored, must be able to support the features of the graph that is read. For example if the GraphML file contains self-loops then the graph provided must also support self-loops. The same for multiple edges. Moreover, the parser completely ignores the attribute "edgedefault" which denotes whether an edge is directed or not. Whether edges are directed or not depends on the underlying implementation of the user provided graph object.
The importer by default validates the input using the 1.0
GraphML Schema. The user can
(not recommended) disable the validation by calling setSchemaValidation(boolean)
.
Constructor and Description |
---|
SimpleGraphMLImporter()
Constructs a new importer.
|
Modifier and Type | Method and Description |
---|---|
void |
addEdgeAttributeConsumer(BiConsumer<Pair<E,String>,Attribute> consumer)
Add an edge attribute consumer.
|
void |
addGraphAttributeConsumer(BiConsumer<String,Attribute> consumer)
Add a graph attribute consumer.
|
void |
addVertexAttributeConsumer(BiConsumer<Pair<V,String>,Attribute> consumer)
Add a vertex attribute consumer.
|
String |
getEdgeWeightAttributeName()
Get the attribute name for edge weights
|
void |
importGraph(Graph<V,E> graph,
Reader input)
Import a graph.
|
boolean |
isSchemaValidation()
Whether the importer validates the input
|
protected void |
notifyEdge(E e,
String key,
Attribute value)
Notify for an edge attribute
|
protected void |
notifyGraph(String key,
Attribute value)
Notify for a graph attribute
|
protected void |
notifyVertex(V v,
String key,
Attribute value)
Notify for a vertex attribute
|
void |
removeEdgeAttributeConsumer(BiConsumer<Pair<E,String>,Attribute> consumer)
Remove an edge attribute consumer.
|
void |
removeGraphAttributeConsumer(BiConsumer<String,Attribute> consumer)
Remove a graph attribute consumer.
|
void |
removeVertexAttributeConsumer(BiConsumer<Pair<V,String>,Attribute> consumer)
Remove a vertex attribute consumer.
|
void |
setEdgeWeightAttributeName(String edgeWeightAttributeName)
Set the attribute name to use for edge weights.
|
void |
setSchemaValidation(boolean schemaValidation)
Set whether the importer should validate the input
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
importGraph, importGraph
public String getEdgeWeightAttributeName()
public void setEdgeWeightAttributeName(String edgeWeightAttributeName)
edgeWeightAttributeName
- the attribute namepublic boolean isSchemaValidation()
public void setSchemaValidation(boolean schemaValidation)
schemaValidation
- value for schema validationpublic void importGraph(Graph<V,E> graph, Reader input) throws ImportException
The provided graph must be able to support the features of the graph that is read. For example if the GraphML file contains self-loops then the graph provided must also support self-loops. The same for multiple edges.
importGraph
in interface GraphImporter<V,E>
graph
- the output graphinput
- the input readerImportException
- in case an error occurs, such as I/O or parse errorpublic void addGraphAttributeConsumer(BiConsumer<String,Attribute> consumer)
consumer
- the consumerpublic void removeGraphAttributeConsumer(BiConsumer<String,Attribute> consumer)
consumer
- the consumerpublic void addVertexAttributeConsumer(BiConsumer<Pair<V,String>,Attribute> consumer)
consumer
- the consumerpublic void removeVertexAttributeConsumer(BiConsumer<Pair<V,String>,Attribute> consumer)
consumer
- the consumerpublic void addEdgeAttributeConsumer(BiConsumer<Pair<E,String>,Attribute> consumer)
consumer
- the consumerpublic void removeEdgeAttributeConsumer(BiConsumer<Pair<E,String>,Attribute> consumer)
consumer
- the consumerprotected void notifyGraph(String key, Attribute value)
key
- the attribute keyvalue
- the attributeprotected void notifyVertex(V v, String key, Attribute value)
v
- the vertexkey
- the attribute keyvalue
- the attributeCopyright © 2019. All rights reserved.