STIL

Starlink Tables Infrastructure Library

Generic Java Table Handling for Astronomy

• What is STIL?
• Features
• Generic
• VOTable
• Coming Soon
• Supported Formats
• Documentation
• Downloads
• Further Information

What is STIL?

STIL is a pure Java library for generic input, output and processing of tabular data. It presents to the application programmer a view of a table which looks the same regardless of whether it came from a FITS file, a VOTable, an ASCII text file, a query on a relational database, or whatever. Thus the application doesn't have to worry about the storage format of tables either when reading or writing them, it can concentrate on doing processing. STIL's idea of a table is rich enough to include table and column metadata, and table cells which contain scalar or single- or multi-dimensional array data of numerical, string or other types. This is well suited to astronomical data, though it can be of use in other fields as well.

STIL comes with a large range of supported input and output formats (including VOTable, FITS, SQL, ASCII) and can be extended to cope with still others.

Features

Generic Features

The generic table I/O has the following features:

• Many table serialization formats supported
• Pluggable architecture allows addition of new formats
• Any-to-any format conversion is trivial
• Access to large tables is possible (not constrained by memory)
• Full javadocs and programmer's overview documentation
• GUI components provided including full table drag and drop support

VOTable Features

STIL includes sophisticated facilities for VOTable I/O which can, if desired, be used largely independently of the rest of the package. As well as the general features listed above this has the following features:

• Reads and writes all VOTable data formats (TABLEDATA, FITS, BINARY)
• Full access to hierarchical document structure
• Flexible table output (you can construct hierarchical documents)
• Hybrid SAX/DOM parsing for efficient input
• Parsing does not attempt network connections to retrieve VOTable DTD/schema
• Best-efforts parsing of non-conforming/invalid documents

Coming Soon

STIL development is ongoing. Future development should include:

• Verstatile and efficient facilities for table joins based on exact or fuzzy coordinate matches (actually this is already in the library, but not fully documented or supported)
• Table sorting facilities
• A set of tools providing the facilities from the command line
• More I/O handlers
• Proper handling of astronomical coordinates
• VOTable 1.1 features (including GROUP elements)

Supported Formats

The following formats are currently supported for table input:

• FITS
• VOTable
• SQL
• ASCII
• World Data Center

• FITS
• VOTable
• SQL
• Human-readable text
• HTML
• LaTeX
• Mirage

Documentation

There are two main sources of documentation for STIL:

• The main programmer's overview document is SUN/252, available as:
• Multi-page HTML document
• Single HTML document
• PDF file
• XML source
• The definitive API documentation is available in the javadocs:
• Browse javadocs online

You can download the full documentation set (SUN/252 in various forms plus javadocs) in the documentation zip file.

Downloads

STIL is released under the GPL. The main components are available here:

• Standalone jar file (compiled classes)
• Documentation zip file
• Source code zip file

There are alternative ways of obtaining the compiled classes:

• Download TOPCAT (all the STIL libraries are contained in the TOPCAT installation)
• Download the entire Starlink java set, of which STIL forms part
• Get the Starlink CD (ISO image) containing all Starlink software - but note the most recent version of STIL is not on it yet

Note that while the source code archive above contains all the original code in STIL, it may not suffice to build it. If you need build files etc, contact me.

STIL has been developed using J2SE 1.4.1, but is expected to work with any 1.4 version of the J2SE.

Further Information

If you like STIL, you'll love TOPCAT, a graphical tool for table browsing / plotting / analysis / editing which benefits from all STIL's features.

If you have any comments, questions, requests, bugs etc, please contact me:

• Author: Mark Taylor, Astrophysics group, Physics Department, Bristol University
• Email: m.b.taylor@bristol.ac.uk
• STIL WWW page: http://www.starlink.ac.uk/stil/
• Starlink: http://www.starlink.ac.uk/