Package net.ontopia.topicmaps.xml

Class AbstractTopicMapExporter

java.lang.Object

net.ontopia.topicmaps.xml.AbstractTopicMapExporter

Direct Known Subclasses:

TMXMLWriter, XTM2TopicMapExporter, XTMTopicMapExporter

public abstract class AbstractTopicMapExporter
extends Object

INTERNAL: Abstract class providing common operations used by XML exporters.

Field Summary

Fields

Modifier and Type	Field	Description
protected boolean	add_ids	INTERNAL: Whether or not IDs should be added to all elements.
protected static String	EMPTY_LOCALNAME
protected static String	EMPTY_NAMESPACE
protected Predicate	filter

Constructor Summary

Constructors

Constructor	Description
AbstractTopicMapExporter()

Method Summary

Modifier and Type	Method	Description
protected void	addId(AttributesImpl atts, TMObjectIF tmobject)
protected Collection	filterCollection(Collection unfiltered)	Filter a whole collection of objects.
protected boolean	filterOk(Object unfiltered)	INTERNAL: Filter a single object.
String	getElementId(TMObjectIF tmobject)	INTERNAL: Method used to extract the XTM element id from a topic map object when a source locator relative to the topic map base address exists.
protected boolean	isValidXMLId(String id)	INTERNAL: Used to test whether the ID is a syntactically valid XML ID.
static boolean	mayCollide(String id)	INTERNAL: Used to find out whether this ID may collide with IDs produced from object IDs.
void	setFilter(Predicate filter)	PUBLIC: Sets the filter that decides which topic map constructs are accepted in the exported TM/XML.

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_NAMESPACE

protected static final String EMPTY_NAMESPACE

See Also:

Constant Field Values

EMPTY_LOCALNAME

protected static final String EMPTY_LOCALNAME

See Also:

Constant Field Values

filter

protected Predicate filter

add_ids

protected boolean add_ids

INTERNAL: Whether or not IDs should be added to all elements.

Constructor Detail

AbstractTopicMapExporter

public AbstractTopicMapExporter()

Method Detail

setFilter

public void setFilter(Predicate filter)

PUBLIC: Sets the filter that decides which topic map constructs are accepted in the exported TM/XML. Uses 'filter' to identify individual topic constructs as allowed or disallowed. TM constructs that depend on the disallowed topics are also disallowed.

Parameters:

filter - Places constraints on individual topicmap constructs.

Since:

3.2

filterCollection

protected Collection filterCollection(Collection unfiltered)

Filter a whole collection of objects.

Parameters:

unfiltered - The objects to filter.

Returns:

A new collection containing all objects accepted by the filter, or if this.filter is null, returns the original collection.

filterOk

protected boolean filterOk(Object unfiltered)

INTERNAL: Filter a single object.

Parameters:

unfiltered - The object to filter.

Returns:

True if the object is accepted by the filter or the filter is null. False otherwise.

addId

protected void addId(AttributesImpl atts,
                     TMObjectIF tmobject)

getElementId

public String getElementId(TMObjectIF tmobject)

INTERNAL: Method used to extract the XTM element id from a topic map object when a source locator relative to the topic map base address exists.

This method is critical because we want to preserve the connection between subject indicators used to reify local objects, and at the same time we wish to keep the symbolic IDs often used in XTM and LTM files.

When setting the IDs of elements we set the ID to "fragment" if the object has a source locator of the form "base#fragment", where base is the base address of the topic map store. If no such source locator is found, the ID becomes "id" + object ID.

See the getSubjectIndicatorRef method in XTMTopicMapExporter to see how subject indicators are exported. Synchronization of these two methods is vital.

mayCollide

public static boolean mayCollide(String id)

INTERNAL: Used to find out whether this ID may collide with IDs produced from object IDs. See bug #654. Works for both id234234 and idT234234.

isValidXMLId

protected boolean isValidXMLId(String id)

INTERNAL: Used to test whether the ID is a syntactically valid XML ID.