eu.ehri.project.importers.ead

Class EadHandler

java.lang.Object

org.xml.sax.helpers.DefaultHandler

eu.ehri.project.importers.base.SaxXmlHandler

eu.ehri.project.importers.ead.EadHandler

All Implemented Interfaces:

ContentHandler, DTDHandler, EntityResolver, ErrorHandler, LexicalHandler

Direct Known Subclasses:

UshmmHandler

public class EadHandler
extends SaxXmlHandler

Handler of EAD files. Use to create a representation of the structure of Documentary Units. This generic handler does not do tricks to get data from any CHI-custom use of EAD - you should extend this class for that. If there is no language, it does set the language of the description to English. makes use of icaatom.properties with format: part/of/path/=attribute

Field Summary

Fields

Modifier and Type	Field and Description
protected List<DocumentaryUnit>[]	children

Fields inherited from class eu.ehri.project.importers.base.SaxXmlHandler

currentEntity, currentGraphPath, currentPath, currentText, depth, importer, languageMap, locator, properties

Constructor Summary

Constructors

Constructor and Description
EadHandler(ItemImporter<Map<String,Object>,?> importer) Create an EadHandler using some importer.
EadHandler(ItemImporter<Map<String,Object>,?> importer, XmlImportProperties properties) Create an EadHandler using some importer, and a mapping of paths to node properties.

Method Summary

Modifier and Type	Method and Description
protected void	addOtherIdentifier(Map<String,Object> currentGraph, String otherIdentifier) Helper method to add identifiers to the list of other identifiers.
void	endElement(String uri, String localName, String qName) Called when the XML parser encounters an end tag.
protected void	extractIdentifier(Map<String,Object> currentGraph) Handler-specific code for extraction or generation of unit IDs.
protected void	extractTitle(Map<String,Object> currentGraph) if no NAME_KEY is provided, use the IDENTIFIER_KEY
protected String	getSourceFileId()
protected boolean	needToCreateSubNode(String qName) Determines whether a new node that is a 'child' of the current node (i.e.
protected List<String>	pathIds() Get the full 'path of identifiers' of the current node.
InputSource	resolveEntity(String publicId, String systemId) Set a custom resolver so EAD DTDs are never looked up online.
void	startElement(String uri, String localName, String qName, Attributes attributes) Receive an opening tag.
protected void	useDefaultLanguage(Map<String,Object> currentGraph) Checks given currentGraph for a language and sets a default language code for the description if no language is found.

Methods inherited from class eu.ehri.project.importers.base.SaxXmlHandler

characters, comment, endCDATA, endDTD, endEntity, getMappedProperty, overwritePropertyInCurrentGraph, printGraph, putPropertyInCurrentGraph, putSubGraphInCurrentGraph, setDocumentLocator, startCDATA, startDTD, startEntity

Methods inherited from class org.xml.sax.helpers.DefaultHandler

endDocument, endPrefixMapping, error, fatalError, ignorableWhitespace, notationDecl, processingInstruction, skippedEntity, startDocument, startPrefixMapping, unparsedEntityDecl, warning

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.xml.sax.ContentHandler

endDocument, endPrefixMapping, ignorableWhitespace, processingInstruction, skippedEntity, startDocument, startPrefixMapping

Field Detail

children

protected final List<DocumentaryUnit>[] children

Constructor Detail

EadHandler

public EadHandler(ItemImporter<Map<String,Object>,?> importer)

Create an EadHandler using some importer. The default mapping of paths to node properties is used.

Parameters:

importer - the importer instance

EadHandler

public EadHandler(ItemImporter<Map<String,Object>,?> importer,
                  XmlImportProperties properties)

Create an EadHandler using some importer, and a mapping of paths to node properties.

Parameters:

importer - the importer instance

properties - an XML node properties instance

Method Detail

resolveEntity

public InputSource resolveEntity(String publicId,
                                 String systemId)
                          throws SAXException,
                                 IOException

Set a custom resolver so EAD DTDs are never looked up online.

Specified by:

resolveEntity in interface EntityResolver

Overrides:

resolveEntity in class org.xml.sax.helpers.DefaultHandler

Throws:

SAXException

IOException

startElement

public void startElement(String uri,
                         String localName,
                         String qName,
                         Attributes attributes)
                  throws SAXException

Description copied from class: SaxXmlHandler

Receive an opening tag. Initialise the current text to store the characters, create a language map to hold descriptions in different languages, push the level if this element warrants a new sub-node and store the attributes that need to be stored.

Specified by:

startElement in interface ContentHandler

Overrides:

startElement in class SaxXmlHandler

Throws:

SAXException

pathIds

protected List<String> pathIds()

Get the full 'path of identifiers' of the current node.

Returns:

a List of Strings, i.e. identifiers, representing the path of the current node

endElement

public void endElement(String uri,
                       String localName,
                       String qName)
                throws SAXException

Called when the XML parser encounters an end tag. This is tuned for EAD files, which come in many flavours.

Certain elements represent subcollections, for which we create new nodes (here, we create representative Maps for nodes). Many EAD producers use the standard in their own special way, so this method calls generalised methods to filter, get data in the right place and reformat. If a collection of EAD files need special treatment to get specific data in the right place, you only need to override the other methods (in order: extractIdentifier, extractTitle, extractDate).

Specified by:

endElement in interface ContentHandler

Overrides:

endElement in class SaxXmlHandler

Throws:

SAXException

getSourceFileId

protected String getSourceFileId()

Returns:

the <eadid>, extended with the languageTag or null if it was not parsed yet or empty

useDefaultLanguage

protected void useDefaultLanguage(Map<String,Object> currentGraph)

Checks given currentGraph for a language and sets a default language code for the description if no language is found.

Parameters:

currentGraph - Data at the current node level

extractTitle

protected void extractTitle(Map<String,Object> currentGraph)

if no NAME_KEY is provided, use the IDENTIFIER_KEY

Parameters:

currentGraph - Data at the current node level

extractIdentifier

protected void extractIdentifier(Map<String,Object> currentGraph)

Handler-specific code for extraction or generation of unit IDs. Default method is empty; override when necessary.

Parameters:

currentGraph - Data at the current node level

addOtherIdentifier

protected void addOtherIdentifier(Map<String,Object> currentGraph,
                                  String otherIdentifier)

Helper method to add identifiers to the list of other identifiers. The property named Ontology.OTHER_IDENTIFIERS (i.e. "otherIdentifiers") is always an ArrayList of Strings.

Parameters:

currentGraph - the node representation to add the otherIdentifier to

otherIdentifier - the alternative identifier to add

needToCreateSubNode

protected boolean needToCreateSubNode(String qName)

Description copied from class: SaxXmlHandler

Determines whether a new node that is a 'child' of the current node (i.e. a 'sub-node') needs to be created, based on the qualified element name.

Specified by:

needToCreateSubNode in class SaxXmlHandler

Parameters:

qName - the QName

Returns:

true if the QName warrants a sub-node, false otherwise