Office of the President
California Digital Library Announces New
Release of the eXtensible Text Framework (XTF)
Oakland, CA, May 12, 2008 - The California Digital
Library (CDL) is pleased to announce a new release of its search and display
technology, the eXtensible
Text Framework (XTF) version 2.1 (http://www.cdlib.org/inside/projects/xtf/
). XTF is an open source, highly flexible
software application that supports the search, browse and display of
heterogeneous digital content. XTF
offers efficient and practical methods for creating customized end-user
interfaces for distinct digital content collections.
Highlights from the 2.1 release
interface improvements, including new search forms, built-in faceted browsing,
and a new look and feel.
support for document and information exchange formats.
and OAI-PMH output
article format indexing and output
XSLT stylesheets for simpler deployment and adaptation.
documentation that has been moved to the XTF project wiki, allowing XTF
implementers to share solutions with entire user community.
Boolean query language, offered as an experimental feature.
compatibility with existing XTF implementations.
A complete list of
changes is available on the XTF Project page on SourceForge,
where the distribution (including documentation) can also be downloaded.
Since the first deployment of XTF
in 2005, the development strategy has been to build and maintain an indexing and
display technology that is not only customizable, but also draws upon tested
components already in use by the digital library and search communities - in
particular the Lucene text search engine, Java, XML, and XSLT. By coordinating these pieces in a single
platform that can be used to create multiple unique applications, CDL has
succeeded in dramatically reducing the investment in infrastructure, staff
training and development for new digital content projects.
XTF offers a suite of
customizable features that support diverse intellectual access to content. Interfaces can be designed to support
the distinct tools and presentations that are useful and meaningful to specific
audiences. In addition, XTF offers
the following core features:
- Easy to deploy: Drops directly in to a
Java application server such as Tomcat or Resin; has been tested on Solaris,
Mac, Linux, and Windows operating systems.
- Easy to configure: Can create indexes on
any XML element or attribute; entire presentation layer is customizable via
Optimized to perform well on large documents (e.g., a single text
that exceeds 10MB of encoded text); scales to perform well on collections of
millions of documents; provides full Unicode support.
well with a variety of authentication systems (e.g., IP address lists, LDAP,
an interface for external data lookups to support thesaurus-based term
expansion, recommender systems, etc.
power other digital library services (e.g., XTF contains an OAI-PMH data
provider that allows others to harvest metadata, and an SRU interface that
exposes searches to federated search engines).
- Can be deployed as separate, modular pieces of a
third-party system (e.g., the module that displays snippets of matching
- Powerful for
the end user:
checking of queries
displays for browsing
updated browse lists
These basic features can be
tuned and modified. For instance,
the same bookbag feature that allows users to store links to entire books, can
also store links to citable elements of an object, such as a note or other
A sampling of XTF-based
applications both within and outside of the CDL include: