Development history
The development of the Java Announcement Display System began in 2004 to solve a specific digital signage requirement in the electronics department at the University of Kent.
The department purchased a large plasma screen for the foyer to display information to students entering the building. It was hoped that the screen could display important announcements such as cancelled lectures and classes to reduce the burden on staff and scraps of paper to relay information. The idea was let down by lack of software tools to make it happen. Initially Microsoft PowerPoint presentations and updating web pages were created but it was obvious straight away that updating the content was going to be a problem.
With Microsoft PowerPoint any change to a presentation requires slideshow mode to be closed, the file manually edited and then slideshow mode restarted. The setup in the department made this impossible to achieve because there is no desk or easily accessible input devices near the plasma screen.
What was required was a remote method of updating the screen. One method of remotely updating the screen was to display a webpage that automatically reloaded content periodically. By updating the web page on the server, new content could be displayed. The main problem with this strategy was making the content fit the screen correctly. It was impossible for students to scroll through announcements on the screen so they needed to fit perfectly. Manipulating font sizes before display to fit the necessary space was incredibly difficult because of different configurations for viewing and editing.
The first version of the Java Announcement Display System was designed to read plain text announcements from a remote database and use the available space on the plasma screen to display them efficiently. A small Java Application was developed to achieve this task. The requirement evolved into displaying a sequence of announcements in addition to news items in separate panels. Later a staff list with room numbers and telephone extensions was added, also read from a database. Together with cycling background images, the electronics department had an attractive and effective announcement display system. To add or change content on the screen, the database could be changed using Microsoft Access and the modification would appear instantly on the plasma screen.
A few months later Keynes College at the University of Kent purchased a plasma screen for the new atrium of the building. After hearing of the success of the electronics display software it was the natural choice for the new screen. There were several hurdles to overcome however. Unlike the electronics department, there was no database available to store and maintain content for the screen so a new data management system was required. Another problem was that content needed to be added from number of departments on campus and there was no single person who could take on this roll. The solution would need to make it possible for a number of authors to add content from their personal computers.
Installing custom software for sending announcements from the various systems would have been time consuming and caused numerous problems because of the limitations placed on computers connected to the University network. It was decided that the best strategy would be to couple the display system with a web server. By serving custom form elements on web pages, a web browser on any computer could be used to post content to the screen.
The development took several months due to the complexity of linking the full screen graphics components to a multi-threaded web server and content management system. The announcement display system, written in Java, was given the name JADS and issued to Keynes college in 2005.
Several additional enhancements were added in this new version. Announcements were no longer restricted to plain text. Images could be uploaded and displayed on the screen. JADS took care of rescaling and displaying the images in the available space alongside other components. The layout of items on the screen could also be controlled through the use of templates and switched within the web based user interface.
Further interest in JADS prompted the development of a more flexible design using emerging technologies. RSS feeds were used to encapsulate collections of multimedia announcements. RSS opened up the possibility of reading news and other information from the Internet and displaying it on the screen. Additional custom components were developed such as the analogue clock and live updating images for webcam image streaming. Another improvement was the ability to cycle through multiple templates with customisation options available.
Towards the end of 2005 a demonstration version of JADS was put online at www.jads.co.uk. During 2006 the website received approximately 8,000 visitors and the demonstration version was installed on 91 computers. This traffic was purely search engine traffic and no attempts were made to optimise content or submit JADS to directories or advertising services online.
In 2006 the Architecture Department at the University of Kent requested a version of JADS customised to display timetable data. This new requirement prompted a major rewrite of and many additional features were added.
JADS can now display timetable data for up to 10 concurrent timelines. JADS provides a user interface to add events from a standard web browser. Timetable images are dynamically created and can be served to be used elsewhere on the local Intranet. Another major change to JADS was the slide designer. Previous versions had the ability to change the template used for positioning items but queuing multiple template designs for sequential display of specific items was impossible. Version 4 of JADS provides a more familiar slide creating structure to other presentation packages such as Microsoft PowerPoint. The web based user interface has also been significantly improved with live updating previews throughout the system.
In February 2007 the JADS website was updated with version 4 of JADS and a new design. Online version 4 incorporates a licence management system. JADS initially displays a slide that can not be removed. The slide promotes purchasing a licence and is linked to an RSS feed that can be used for custom advertising. To remove the slide and advertising, a licence must be purchased.
JADS is in a process of continuous development and change. If you are interested in a custom JADS installation please contact:
