org.dspace.content.crosswalk

Class OREDisseminationCrosswalk

java.lang.Object

org.dspace.content.crosswalk.OREDisseminationCrosswalk

All Implemented Interfaces:

DisseminationCrosswalk

public class OREDisseminationCrosswalk
extends Object
implements DisseminationCrosswalk

ORE dissemination crosswalk

Produces an Atom-encoded ORE aggregation of a DSpace item.

Version:

$Revision: 1 $

Author:

Alexey Maslov

Field Summary

Fields

Modifier and Type	Field and Description
static org.jdom.Namespace	ATOM_NS
static String	ATOM_RNG

Fields inherited from interface org.dspace.content.crosswalk.DisseminationCrosswalk

XSI_NS

Constructor Summary

Constructors

Constructor and Description
OREDisseminationCrosswalk()

Method Summary

Methods

Modifier and Type	Method and Description
boolean	canDisseminate(DSpaceObject dso) Predicate: Can this disseminator crosswalk the given object.
org.jdom.Element	disseminateElement(DSpaceObject dso) Execute crosswalk, returning one XML root element as a JDOM Element object.
List<org.jdom.Element>	disseminateList(DSpaceObject dso) Execute crosswalk, returning List of XML elements.
org.jdom.Namespace[]	getNamespaces() Get XML namespaces of the elements this crosswalk may return.
String	getSchemaLocation() Get the XML Schema location(s) of the target metadata format.
boolean	preferList() Predicate: Does this disseminator prefer to return a list of Elements, rather than a single root Element?

Methods inherited from class java.lang.Object

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

Field Detail

ATOM_RNG

public static final String ATOM_RNG

See Also:

Constant Field Values

ATOM_NS

public static final org.jdom.Namespace ATOM_NS

Constructor Detail

OREDisseminationCrosswalk

public OREDisseminationCrosswalk()

Method Detail

getNamespaces

public org.jdom.Namespace[] getNamespaces()

Description copied from interface: DisseminationCrosswalk

Get XML namespaces of the elements this crosswalk may return. Returns the XML namespaces (as JDOM objects) of the root element.

Specified by:

getNamespaces in interface DisseminationCrosswalk

Returns:

array of namespaces, which may be empty.

getSchemaLocation

public String getSchemaLocation()

Description copied from interface: DisseminationCrosswalk

Get the XML Schema location(s) of the target metadata format. Returns the string value of the xsi:schemaLocation attribute that should be applied to the generated XML.

It may return the empty string if no schema is known, but crosswalk authors are strongly encouraged to implement this call so their output XML can be validated correctly.

Specified by:

getSchemaLocation in interface DisseminationCrosswalk

Returns:

SchemaLocation string, including URI namespace, followed by whitespace and URI of XML schema document, or empty string if unknown.

disseminateElement

public org.jdom.Element disseminateElement(DSpaceObject dso)
                                    throws CrosswalkException,
                                           IOException,
                                           SQLException,
                                           AuthorizeException

Description copied from interface: DisseminationCrosswalk

Execute crosswalk, returning one XML root element as a JDOM Element object. This is typically the root element of a document. Note that, if the implementing class is of type "ContextAwareDisseminationCrosswalk" and a context is present in the method call, you should set the context before calling this method. -> "ContextAwareDisseminationCrosswalk.setContext(org.dspace.core.Context)" The implementing class should then use the "ContextAwareDisseminationCrosswalk.getContext()" and "ContextAwareDisseminationCrosswalk.handleContextCleanup()" to retrieve and commit/complete the context respectively

Specified by:

disseminateElement in interface DisseminationCrosswalk

Parameters:

dso - the DSpace Object whose metadata to export.

Returns:

root Element of the target metadata, never null

Throws:

CrosswalkInternalException - (CrosswalkException) failure of the crosswalk itself.

CrosswalkObjectNotSupported - (CrosswalkException) Cannot crosswalk this kind of DSpace object.

IOException - I/O failure in services this calls

SQLException - Database failure in services this calls

AuthorizeException - current user not authorized for this operation.

CrosswalkException

disseminateList

public List<org.jdom.Element> disseminateList(DSpaceObject dso)
                                       throws CrosswalkException,
                                              IOException,
                                              SQLException,
                                              AuthorizeException

Description copied from interface: DisseminationCrosswalk

Execute crosswalk, returning List of XML elements. Returns a List of JDOM Element objects representing the XML produced by the crosswalk. This is typically called when a list of fields is desired, e.g. for embedding in a METS document xmlData field.

When there are no results, an empty list is returned, but never null.

Specified by:

disseminateList in interface DisseminationCrosswalk

Parameters:

dso - the DSpace Object whose metadata to export.

Returns:

results of crosswalk as list of XML elements.

Throws:

CrosswalkInternalException - (CrosswalkException) failure of the crosswalk itself.

CrosswalkObjectNotSupported - (CrosswalkException) Cannot crosswalk this kind of DSpace object.

IOException - I/O failure in services this calls

SQLException - Database failure in services this calls

AuthorizeException - current user not authorized for this operation.

CrosswalkException

canDisseminate

public boolean canDisseminate(DSpaceObject dso)

Description copied from interface: DisseminationCrosswalk

Predicate: Can this disseminator crosswalk the given object. Needed by OAI-PMH server implementation.

Specified by:

canDisseminate in interface DisseminationCrosswalk

Parameters:

dso - dspace object, e.g. an Item.

Returns:

true when disseminator is capable of producing metadata.

preferList

public boolean preferList()

Description copied from interface: DisseminationCrosswalk

Predicate: Does this disseminator prefer to return a list of Elements, rather than a single root Element?

Some metadata formats have an XML schema without a root element, for example, the Dublin Core and Qualified Dublin Core formats. This would be true for a crosswalk into QDC, since it would "prefer" to return a list, since any root element it has to produce would have to be part of a nonstandard schema. In most cases your implementation will want to return false

Specified by:

preferList in interface DisseminationCrosswalk

Returns:

true when disseminator prefers you call disseminateList().