com.yworks.yfiles.server.graphml.support
Class GraphMLLayoutGraphIOHandler

java.lang.Object
  com.yworks.yfiles.server.graphml.support.GraphMLLayoutGraphIOHandler

public class GraphMLLayoutGraphIOHandler

extends Object

IOHandler for (de)serializing graphs from/to GraphML format. GraphMLLayoutGraphIOHandler supports (de)serialization of custom GraphML attributes that hold data of simple type, as well as ids, and styles as DocumentFragments.

For more information about the GraphML file format please refer to the GraphML Primer.

Field Summary

protected List	edgeOutputHandlers
protected List	graphmlOutputHandlers
protected List	graphOutputHandlers
protected List	inputHandlers
protected List	nodeOutputHandlers
protected List	portOutputHandlers
protected boolean	validationEnabled
protected boolean	writeDTDEnabled
protected boolean	writeXMLSchemaEnabled

Constructor Summary

GraphMLLayoutGraphIOHandler()
Creates a new instance of GraphMLIOHandler.

Method Summary

void	addAttribute(DataMap map, String attrName, int type, int scope) Adds a GraphML attribute with node scope that holds data of simple type.
void	addEdgeAttribute(DataProvider out, DataAcceptor in, String attrName, int type) Adds a GraphML attribute with edge scope that holds data of simple type.
void	addGraphAttribute(DataProvider out, DataAcceptor in, String attrName, int type) Adds a GraphML attribute with graph scope that holds data of simple type.
void	addInputHandler(DOMInputHandler inputHandler) Adds a subordinate input handler to this GraphMLIOHandler.
void	addInputHandler(DOMInputHandler inputHandler, int scope) Deprecated. Use addInputHandler(org.graphdrawing.graphml.reader.dom.DOMInputHandler) instead
void	addNamespace(String namespaceURI, String shortName) Adds a namespace declaration to the GraphML file.
void	addNodeAttribute(DataProvider out, DataAcceptor in, String attrName, int type) Adds a GraphML attribute with node scope that holds data of simple type.
void	addOutputHandler(OutputHandler outputHandler, int scope) Adds a subordinate output handler for the given element scope to this GraphMLIOHandler.
void	addSchemaLocation(String namespace, String schemaLocation) Adds a schema location to the header of a GraphML file.
boolean	canRead() Returns true.
boolean	canWrite() Returns true.
void	clearInputHandlers() Clear all input handlers
protected void	configureParser(DOMGraphMLParser graphMLParser, Graph graph) Configures the parser for the read operations.
protected DirectGraphMLWriter	createDirectGraphMLWriter() Creates and returns a GraphML writer instance.
protected YGraphElementFactory	createGraphElementFactory(Graph graph) Create the factory instance used for reading the graph
protected GraphElementProvider	createGraphElementProvider(Graph graph) Create the provider instance used for writing the graph
GraphMLParseErrorHandler	getErrorHandler() Return the parse error handler that is used by this instance.
String	getFileFormatString() Returns the GraphML file format string.
String	getFileNameExtension() Returns the default file name extension for GraphML files.
DataAcceptor	getGraphIdAcceptor() Return the DataAcceptor instance for graph ids that has been previously registered with setGraphIdAcceptor(y.base.DataAcceptor)
DataProvider	getGraphIdProvider() Return the DataProvider instance for graph ids that has been previously registered with setGraphIdProvider(y.base.DataProvider)
String	getGraphmlCoreNS() Get the namespace URI where the core GraphML elements live.
DataAcceptor	getIdDataAcceptor() Return the DataAcceptor instance for graph element ids that has been previously registered with setIdDataAcceptor(y.base.DataAcceptor)
DataProvider	getIdDataProvider() Return the DataProvider instance for graph element ids that has been previously registered with setIdDataProvider(y.base.DataProvider)
Collection	getInputHandlers() Returns the registered input handlers for GraphML attributes that are registered with this GraphMLIOHandler.
Collection	getInputHandlers(int scope) Deprecated. Use getInputHandlers() instead
String	getOutputEncoding() Get the output encoding that is used by this handler instance.
Collection	getOutputHandlers(int scope) Returns an editable view on the registered output handlers for GraphML attributes with given scope that are registered with this GraphMLIOHandler.
SerializerRegistry	getSerializerRegistry()
boolean	isReadEmbeddedResources() Returns whether embedded resources should be evaluated.
boolean	isValidationEnabled() Returns if a validating parser is used.
boolean	isWriteDTDEnabled() Returns if a reference to the GraphML DTD should be written.
boolean	isWriteEmbeddedResources() Returns whether embedded resources should be written in a separate block.
boolean	isWriteXMLSchemaEnabled() Returns if a reference to the GraphML XML Schema definition should be written.
void	read(Graph graph, InputStream is) Reads a GraphML file from the given input stream and populates the Graph2D object.
void	read(Graph graph, Node n) Reads a Graph from a preparsed DOM tree object.
void	read(Graph graph, String name) Fills the contents of the given graph from a file.
void	read(Graph graph, URL url) Fills the contents of the given graph from a URL.
void	removeInputHandler(DOMInputHandler handler) unregister an inputhandler
void	setErrorHandler(GraphMLParseErrorHandler errorHandler) Set a custom parse error handler that is used by this instance.
void	setGraphIdAcceptor(DataAcceptor graphIdAcceptor) Register a DataAcceptor instance that stores graphml graph element ids for each graph itself.
void	setGraphIdProvider(DataProvider graphIdProvider) Register a DataProvider instance that provides graphml element ids for each graph itself.
void	setGraphmlCoreNS(String graphmlCoreNS) Set the namespace URI where the core GraphML elements live.
void	setIdDataAcceptor(DataAcceptor idDataAcceptor) Register a DataAcceptor instance that stores graphml element ids.
void	setIdDataProvider(DataProvider idDataProvider) Register a DataProvider instance that provides graphml element ids for each element.
void	setOutputEncoding(String outputEncoding) Set a specific encoding for the output.
void	setReadEmbeddedResources(boolean readEmbeddedResource) Set whether embedded resources should be evaluated.
void	setSerializerRegistry(SerializerRegistry serializerRegistry)
void	setValidationEnabled(boolean b) Sets if a validating parser is used.
void	setWriteDTDEnabled(boolean b) Sets if a reference to the GraphML DTD should be written.
void	setWriteEmbeddedResources(boolean writeEmbeddedResource) Set whether embedded resources should be written in a separate block.
void	setWriteXMLSchemaEnabled(boolean b) Returns if a reference to the GraphML XML Schema definition should be written.
void	write(Graph graph, OutputStream os) Writes the given Graph2D object to the output stream creating a GraphML file.
void	write(Graph graph, Result result) Writes the given Graph2D object to a Transformer result.
void	write(Graph graph, String name) Writes the contents of the given graph to a file.
void	write(Graph graph, Writer writer) Writes the given Graph2D object to the output stream creating a GraphML file.

Methods inherited from class java.lang.Object

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

Field Detail

writeDTDEnabled

protected boolean writeDTDEnabled

writeXMLSchemaEnabled

protected boolean writeXMLSchemaEnabled

validationEnabled

protected boolean validationEnabled

inputHandlers

protected List inputHandlers

graphOutputHandlers

protected List graphOutputHandlers

graphmlOutputHandlers

protected List graphmlOutputHandlers

portOutputHandlers

protected List portOutputHandlers

nodeOutputHandlers

protected List nodeOutputHandlers

edgeOutputHandlers

protected List edgeOutputHandlers

Constructor Detail

GraphMLLayoutGraphIOHandler

public GraphMLLayoutGraphIOHandler()

Creates a new instance of GraphMLIOHandler. By default, realizer serializers for all yFiles node and edge realizer implementations as found in package y.view are already registered. Also provided by default is support for post-processors.

See Also:

PostprocessorInputHandler

Method Detail

getOutputEncoding

public String getOutputEncoding()

Get the output encoding that is used by this handler instance. Default is UTF-8

Returns:

the current output encoding

setOutputEncoding

public void setOutputEncoding(String outputEncoding)

Set a specific encoding for the output. Default is UTF-8

Parameters:

outputEncoding - custom output encoding

isReadEmbeddedResources

public boolean isReadEmbeddedResources()

Returns whether embedded resources should be evaluated. If false, no resources are read from an embedded resource data tag. The exact behaviour in this case depends on the InputHandler used (i.e. resolve an external URL instead). Default is true.

Returns:

whether embedded resources should be read if present.

setReadEmbeddedResources

public void setReadEmbeddedResources(boolean readEmbeddedResource)

Set whether embedded resources should be evaluated. If false, no resources are read from an embedded resource data tag. The exact behaviour in this case depends on the InputHandler used (i.e. resolve an external URL instead). Default is true.

Parameters:

readEmbeddedResource - whether embedded resources should be read if present.

isWriteEmbeddedResources

public boolean isWriteEmbeddedResources()

Returns whether embedded resources should be written in a separate block. If false, no resources are embedded in the graphml file. The exact behaviour in this case depends on the OutputHandler used. Default is true.

Returns:

whether embedded resources should be written in a separate block.

setWriteEmbeddedResources

public void setWriteEmbeddedResources(boolean writeEmbeddedResource)

Set whether embedded resources should be written in a separate block. If false, no resources are embedded in the graphml file. The exact behaviour in this case depends on the OutputHandler used. Default is true.

Parameters:

writeEmbeddedResource - whether embedded resources should be written in a separate block.

getErrorHandler

public GraphMLParseErrorHandler getErrorHandler()

Return the parse error handler that is used by this instance.

Returns:

the parse error handler that is used by this instance.

setErrorHandler

public void setErrorHandler(GraphMLParseErrorHandler errorHandler)

Set a custom parse error handler that is used by this instance. If this is not set, a default implementation that handles some common cases is used.

Parameters:

errorHandler - the parse error handler that should be used by this instance.

getGraphmlCoreNS

public String getGraphmlCoreNS()

Get the namespace URI where the core GraphML elements live. By default, this is set to "http://graphml.graphdrawing.org/xmlns/graphml" for compatibility with older yfiles GraphML releases, however, the official GraphML namespace is now "http://graphml.graphdrawing.org/xmlns"

Returns:

the namespace URI where the core GraphML elements live

setGraphmlCoreNS

public void setGraphmlCoreNS(String graphmlCoreNS)

Set the namespace URI where the core GraphML elements live. By default, this is set to "http://graphml.graphdrawing.org/xmlns/graphml" for compatibility with older yfiles GraphML releases, however, the official GraphML namespace is now "http://graphml.graphdrawing.org/xmlns"

Parameters:

graphmlCoreNS - the namespace URI where the core GraphML elements live

getSerializerRegistry

public SerializerRegistry getSerializerRegistry()

setSerializerRegistry

public void setSerializerRegistry(SerializerRegistry serializerRegistry)

getFileFormatString

public String getFileFormatString()

Returns the GraphML file format string.

getFileNameExtension

public String getFileNameExtension()

Returns the default file name extension for GraphML files.

Returns:

graphml

canRead

public boolean canRead()

Returns true.

canWrite

public boolean canWrite()

Returns true.

addInputHandler

public void addInputHandler(DOMInputHandler inputHandler,
                            int scope)

Deprecated. Use addInputHandler(org.graphdrawing.graphml.reader.dom.DOMInputHandler) instead

Adds a subordinate input handler for the given element scope to this GraphMLIOHandler. This is deprecated, use addInputHandler(org.graphdrawing.graphml.reader.dom.DOMInputHandler) and test the scope in DOMInputHandler.acceptKey(org.w3c.dom.NamedNodeMap,int) instead

Parameters:

inputHandler - the input handler to be added.

scope - This parameter is unused

addInputHandler

public void addInputHandler(DOMInputHandler inputHandler)

Adds a subordinate input handler to this GraphMLIOHandler. The scope is determined by the for attribute of the key node

Parameters:

inputHandler - the input handler to be added.

addOutputHandler

public void addOutputHandler(OutputHandler outputHandler,
                             int scope)

Adds a subordinate output handler for the given element scope to this GraphMLIOHandler.

Parameters:

outputHandler - the output handler to be added.

scope - Scope specifier; one of GraphMLConstants.SCOPE_GRAPH, GraphMLConstants.SCOPE_GRAPHML, GraphMLConstants.SCOPE_NODE, or GraphMLConstants.SCOPE_EDGE.

getInputHandlers

public Collection getInputHandlers()

Returns the registered input handlers for GraphML attributes that are registered with this GraphMLIOHandler.

Returns:

All registered subordinate input handlers for GraphML.

getInputHandlers

public Collection getInputHandlers(int scope)

Deprecated. Use getInputHandlers() instead

Returns the registered input handlers for GraphML attributes that are registered with this GraphMLIOHandler. This is deprecated, use addInputHandler(org.graphdrawing.graphml.reader.dom.DOMInputHandler) and test the scope in DOMInputHandler.acceptKey(org.w3c.dom.NamedNodeMap,int) instead

Parameters:

scope - This parameter is unused

Returns:

All registered subordinate input handlers for GraphML.

clearInputHandlers

public void clearInputHandlers()

Clear all input handlers

removeInputHandler

public void removeInputHandler(DOMInputHandler handler)

unregister an inputhandler

Parameters:

handler -

getOutputHandlers

public Collection getOutputHandlers(int scope)

Returns an editable view on the registered output handlers for GraphML attributes with given scope that are registered with this GraphMLIOHandler. Output handlers can be added or removed from the returned collection.

Parameters:

scope - Scope specifier; one of GraphMLConstants.SCOPE_GRAPH, GraphMLConstants.SCOPE_NODE, or GraphMLConstants.SCOPE_EDGE.

Returns:

All registered subordinate output handlers for GraphML attributes with given scope.

createDirectGraphMLWriter

protected DirectGraphMLWriter createDirectGraphMLWriter()

Creates and returns a GraphML writer instance. Note that this method is also invoked to create the GraphML writer that is used with this GraphMLIOHandler.

addAttribute

public void addAttribute(DataMap map,
                         String attrName,
                         int type,
                         int scope)

Adds a GraphML attribute with node scope that holds data of simple type. Supported are Java types such as boolean, int, long, float, double, and String.

Note that the currently used yFiles data accessor implementations type-cast Java types long and float to int and double, respectively.

Parameters:

map - The node map that is accessed by both input and output handler whenever actual data for a node is to be read from or written to a GraphML file.

attrName - The name that is used inside the GraphML file with the XML attr.name attribute of the GraphML <key> element.

type - Type specifier as defined in interface AttributeConstants.

scope - the GraphMLConstants scope to use.

addGraphAttribute

public void addGraphAttribute(DataProvider out,
                              DataAcceptor in,
                              String attrName,
                              int type)

Adds a GraphML attribute with graph scope that holds data of simple type. Supported are Java types such as boolean, int, long, float, double, and String.

Note that the currently used yFiles data accessor implementations type-cast Java types long and float to int and double, respectively.

Parameters:

out - The data provider that is accessed by the output handler whenever actual data for a graph is to be written to a GraphML file.

in - The data acceptor that is accessed by the input handler whenever actual data for a graph is to be read from a GraphML file.

attrName - The name that is used inside the GraphML file with the XML attr.name attribute of the GraphML <key> element.

type - Type specifier as defined in interface AttributeConstants.

addNodeAttribute

public void addNodeAttribute(DataProvider out,
                             DataAcceptor in,
                             String attrName,
                             int type)

Adds a GraphML attribute with node scope that holds data of simple type. Supported are Java types such as boolean, int, long, float, double, and String.

Note that the currently used yFiles data accessor implementations type-cast Java types long and float to int and double, respectively.

Parameters:

out - The data provider that is accessed by the output handler whenever actual data for a node is to be written to a GraphML file.

in - The data acceptor that is accessed by the input handler whenever actual data for a node is to be read from a GraphML file.

attrName - The name that is used inside the GraphML file with the XML attr.name attribute of the GraphML <key> element.

type - Type specifier as defined in interface AttributeConstants.

addEdgeAttribute

public void addEdgeAttribute(DataProvider out,
                             DataAcceptor in,
                             String attrName,
                             int type)

Adds a GraphML attribute with edge scope that holds data of simple type. Supported are Java types such as boolean, int, long, float, double, and String.

Parameters:

out - The data provider that is accessed by the output handler whenever actual data for an edge is to be written to a GraphML file.

in - The data acceptor that is accessed by the input handler whenever actual data for an edge is to be read from a GraphML file.

attrName - The name that is used inside the GraphML file with the XML attr.name attribute of the GraphML <key> element.

type - Type specifier as defined in interface AttributeConstants.

isValidationEnabled

public boolean isValidationEnabled()

Returns if a validating parser is used.

isWriteDTDEnabled

public boolean isWriteDTDEnabled()

Returns if a reference to the GraphML DTD should be written.

isWriteXMLSchemaEnabled

public boolean isWriteXMLSchemaEnabled()

Returns if a reference to the GraphML XML Schema definition should be written.

setValidationEnabled

public void setValidationEnabled(boolean b)

Sets if a validating parser is used.

setWriteDTDEnabled

public void setWriteDTDEnabled(boolean b)

Sets if a reference to the GraphML DTD should be written.

setWriteXMLSchemaEnabled

public void setWriteXMLSchemaEnabled(boolean b)

Returns if a reference to the GraphML XML Schema definition should be written.

addNamespace

public void addNamespace(String namespaceURI,
                         String shortName)

Adds a namespace declaration to the GraphML file.

addSchemaLocation

public void addSchemaLocation(String namespace,
                              String schemaLocation)

Adds a schema location to the header of a GraphML file.

write

public void write(Graph graph,
                  String name)
           throws IOException

Writes the contents of the given graph to a file.

Parameters:

name - The name of the output file

Throws:

IOException

read

public void read(Graph graph,
                 String name)
          throws IOException

Fills the contents of the given graph from a file.

Parameters:

name - The name of the file to be read.

Throws:

IOException

read

public void read(Graph graph,
                 URL url)
          throws IOException

Fills the contents of the given graph from a URL.

Parameters:

url - The url of the resource to be read.

Throws:

IOException

write

public void write(Graph graph,
                  OutputStream os)
           throws IOException

Writes the given Graph2D object to the output stream creating a GraphML file. The proper DTD (Document Type Definition), or alternatively XML Schema definition, as well as the XML header is also written.

Note that the graph element provider that is used by the encoder logic to write the GraphML file is chosen depending on whether the Graph2D object has a HierarchyManager associated or not.

Parameters:

graph - The Graph2D object that is to be written to a GraphML file.

os - The output stream that becomes the GraphML file.

Throws:

IOException

See Also:

YGraphElementProvider

write

public void write(Graph graph,
                  Writer writer)
           throws IOException

Writes the given Graph2D object to the output stream creating a GraphML file. The proper DTD (Document Type Definition), or alternatively XML Schema definition, as well as the XML header is also written.

Note that the graph element provider that is used by the encoder logic to write the GraphML file is chosen depending on whether the Graph2D object has a HierarchyManager associated or not.

Parameters:

graph - The Graph2D object that is to be written to a GraphML file.

writer - The writer that becomes the GraphML file.

Throws:

IOException

See Also:

YGraphElementProvider, YHierarchyGraphElementProvider

write

public void write(Graph graph,
                  Result result)
           throws IOException

Writes the given Graph2D object to a Transformer result. The proper DTD (Document Type Definition), or alternatively XML Schema definition, as well as the XML header is also written.

Note that the graph element provider that is used by the encoder logic to write the GraphML file is chosen depending on whether the Graph2D object has a HierarchyManager associated or not.

This method is especially useful if the result should be postprocessed by other XML applications directly (i.e. without re-reading and parsing)

Parameters:

graph - The Graph2D object that is to be written to a GraphML file.

result - The Transformer result that stores the output.

Throws:

IOException

See Also:

YGraphElementProvider, YHierarchyGraphElementProvider

createGraphElementProvider

protected GraphElementProvider createGraphElementProvider(Graph graph)

Create the provider instance used for writing the graph

getIdDataProvider

public DataProvider getIdDataProvider()

Return the DataProvider instance for graph element ids that has been previously registered with setIdDataProvider(y.base.DataProvider)

Returns:

the DataProvider instance for graph element ids that has been previously registered with setIdDataProvider(y.base.DataProvider)

setIdDataProvider

public void setIdDataProvider(DataProvider idDataProvider)

Register a DataProvider instance that provides graphml element ids for each element.

• Note: If this is not set, the framework neither creates IDs for elements for which DataProvider returns no value nor checks for uniqueness of id values in a specific scope, this must be implemented by the dataProvider itself. If this is not set, a default implementation provided by DirectGraphMLWriter will be used.
• Note: Since the structure of the resulting GraphML file may differ from the actual graph structure for graph hierarchies, graph ids for nested graphs must be provided seperately by setGraphIdProvider(y.base.DataProvider)

Parameters:

idDataProvider -

getIdDataAcceptor

public DataAcceptor getIdDataAcceptor()

Return the DataAcceptor instance for graph element ids that has been previously registered with setIdDataAcceptor(y.base.DataAcceptor)

Returns:

the DataAcceptor instance for graph element ids that has been previously registered with setIdDataAcceptor(y.base.DataAcceptor)

setIdDataAcceptor

public void setIdDataAcceptor(DataAcceptor idDataAcceptor)

Register a DataAcceptor instance that stores graphml element ids. This stores a graphml element id for each graph element, except for nested graphs (see setGraphIdAcceptor(y.base.DataAcceptor)

Parameters:

idDataAcceptor -

getGraphIdAcceptor

public DataAcceptor getGraphIdAcceptor()

Return the DataAcceptor instance for graph ids that has been previously registered with setGraphIdAcceptor(y.base.DataAcceptor)

Returns:

the DataAcceptor instance for graph ids that has been previously registered with setGraphIdAcceptor(y.base.DataAcceptor)

setGraphIdAcceptor

public void setGraphIdAcceptor(DataAcceptor graphIdAcceptor)

Register a DataAcceptor instance that stores graphml graph element ids for each graph itself. This stores a graph id for each group node in hierarchic graphs.

Note: This is used for nested graphs, when a graphML graph element has no corresponding ygraph object (i.e. for group nodes)

Parameters:

graphIdAcceptor -

getGraphIdProvider

public DataProvider getGraphIdProvider()

Return the DataProvider instance for graph ids that has been previously registered with setGraphIdProvider(y.base.DataProvider)

Returns:

the DataProvider instance for graph ids that has been previously registered with setGraphIdProvider(y.base.DataProvider)

setGraphIdProvider

public void setGraphIdProvider(DataProvider graphIdProvider)

Register a DataProvider instance that provides graphml element ids for each graph itself. This should provide a graph id for each group node in hierarchic graphs.

• Note: If this is not set, the framework neither creates IDs for elements for which DataProvider returns no value nor checks for uniqueness of id values in a specific scope, this must be implemented by the dataProvider itself. If this is not set, a default implementation provided by DirectGraphMLWriter will be used.
• Note: This is used for nested graphs, when a graphML graph element has no corresponding ygraph object (i.e. for group nodes)

Parameters:

graphIdProvider -

read

public void read(Graph graph,
                 InputStream is)
          throws IOException

Reads a GraphML file from the given input stream and populates the Graph2D object.

Note that the graph element factory that is used by the parser logic to create new graph elements (and eventually also new graphs) is chosen depending on whether the Graph2D object has a HierarchyManager associated or not.

Parameters:

graph - The Graph2D object that is to be populated with nodes and edges as read from the GraphML file.

is - The input stream that holds the GraphML file to be read.

Throws:

IOException

See Also:

YGraphElementFactory, YHierarchyGraphElementFactory

read

public void read(Graph graph,
                 Node n)
          throws IOException

Reads a Graph from a preparsed DOM tree object.

Note that the graph element factory that is used by the parser logic to create new graph elements (and eventually also new graphs) is chosen depending on whether the Graph2D object has a HierarchyManager associated or not. This overload is useful if the IOHandler is used after a chain of TRaX transformations

Note: No validation is performed on the DOM tree by this overload.

Parameters:

graph - The Graph2D object that is to be populated with nodes and edges as read from the GraphML file.

n - The root node of the preparsed DOM tree.

Throws:

IOException

See Also:

YGraphElementFactory, YHierarchyGraphElementFactory

configureParser

protected void configureParser(DOMGraphMLParser graphMLParser,
                               Graph graph)

Configures the parser for the read operations.

Parameters:

graphMLParser - The parser to configure

graph - the graph that will be parsed.

createGraphElementFactory

protected YGraphElementFactory createGraphElementFactory(Graph graph)

Create the factory instance used for reading the graph