Package net.ontopia.topicmaps.core.index

Provides interfaces for the engine's index system; the API for Ontopia topic map indexes.

See:
Description

Interface Summary

ClassInstanceIndexIF	PUBLIC: Interface implemented by objects providing quick lookup facilities to find topics used as types, and the instances of those types, within a topic map.
IndexIF	PUBLIC: A marker interface for all indexes.
NameIndexIF	PUBLIC: Index that holds information about the names of topics in the topic map.
OccurrenceIndexIF	INTERNAL: Index that holds information about occurrences in the topic map.
ScopeIndexIF	PUBLIC: Implemented by objects holding information about topics used as themes in scopes, and about topic map objects that have scope.

Package net.ontopia.topicmaps.core.index Description

Provides interfaces for the engine's index system; the API for Ontopia topic map indexes. This package enables quick retrieval of selected topic map content; using these interfaces, these facilities can be used without any dependencies on the repository-specific backend(s) used for managing the topic map data.
NB that these indexing facilities are likely to be changed, and certain to be extended, when the Topic Map Query Language standard is available, so you are advised to design your application code so that the required changes are easy.

Package Specification

The interfaces in this package provide an API for topic map indexes. Topic map indexes provide straightforward and efficient ways to look up information in a topic map; these facilities are frequently used, and would otherwise require a step by step traversal of the entire topic map.
A typical example is looking up all instances of a given topic type, which with the index system can be achieved with a single method call.

Each topic map has an IndexManagerIF instance associated with it. This index manager object can be used to retrieve specific indexes and also to check what indexes are available, which ones have been loaded and so on.

The indexes currently available are:

• ClassInstanceIndex, which is used to find information about which objects are instances of specific classes.
• LocatorIndex, which is used to find out which locators are used where.
• NameIndex, which is used to find out which names are used where.
• ScopeIndex, which is used to find out where a topic has been used in a scope.

Related Documentation

The purpose and scope of this package is explained further in the Ontopia Engine Developers Guide.

Interface Summary

IndexManagerIF is implemented by objects which manage indexes on a topic map (NB there are currently no facilities for indexing across more than one topic map.)

IndexIF is the common interface for all topicmap indexes. IndexIF is extended by ClassInstanceIF, LocatorIndexIF, NameIndexIF, and ScopeIndexIF. These interfaces have a similar structure; each contains methods that return collections of topic map objects (eg associations, variant names), selected according to some criterion.