The Developer Perspective

Michelle Osmond

Design – Requirements Gathering

• Sales & Research projects– Prototypes/Demos

• User group meetings

• Usability workshops & questionnaires– With close collaborators: resource-intensive process

– Focus on Java Client, not portal

• Support calls– Bugs

– Feature requests

Design - implementation• Service-oriented approach to implementation

– J2EE, EJBs / Java RMI / Web Services

ServerConfiguration

Deployment Execution

Task Archive

Data/WF Storage

Java Client

Servlets Portlets

Web services Command line Web Portal

• Main focus on Java client for workflow development, execution and deployment

Design – create workflows

• Provide framework for users to develop and deploy their own workflows to the portal

– Users manage their own design and evaluation of portal services

Design – deploy workflows

• Basic portal:

– Userspace (file) access

– List of services

– Dynamically generated page for each service

Design – web portal (servlets)

• Jetspeed (portlet-based) portal:

– Users additionally have control over the whole portal site layout

– Can integrate own custom tools as portlets

Design – web portal (portlets)

Technical Strategy• Technologies

– J2EE (JBoss) server, includes portal on embedded Tomcat (servlets, JSPs, Struts).

– Portlets: JSR-168, on Jetspeed 1.6

• Portal Functionality: subset of Java Client, for simpler use

– Userspace access (files and workflows)

– Execution of deployed workflows (services)

– Task management

Also:

– Server administration

Development Issues

• Time / Resources– Portal & its usability not a top priority

– Engine and Java Client have the focus

– Many developer skills needed:• Java RMI, Swing GUIs, Tomcat/J2EE, XML, HTML, CGI,

JavaScript, JSP, Servlets, Struts & Tiles, JSR-168, Applets, AJAX…

• Web design, accessibility, usability, compatibility

Development Issues

• Browser differences– Discourages development of rich interfaces using JavaScript

– Plugin support, e.g. SVG

• Technology limitations– Struts & portlets

• Portal QA– Difficult to do comprehensively

• Maintainability/testing of rich JavaScript interfaces

Evaluation

• Java client has the focus– Usability workshops, questionnaires

• Portal not formally evaluated– Bug reports, feature requests

– Users design and evaluate their own portal services

Lessons Learnt - Good• Deployed services are useful and popular

– Easy to parameterise and execute

– Easy to update and add functionality• Users have complete control over portal services: design, construct

workflow, deploy to web

• Flexible and powerful workflow system

• Portlets allow portals to be easily customised further– Skinning, layout

– New, custom or third-party tools

• Continually developing new features, driven by user requests

Lessons Learnt – Not so good• No formal UI design stage or manager

– Inconsistent look & feel

– UI convenient/intuitive for the developer, not the user

– Deployment tool UI in particular (working on this)

• Awareness of UI problems: existence, importance– “INVALID” bugs, “it’s documented in the manual”

• Interactivity, rich interfaces– More web renderers for parameter entry

– Result visualisation

– Service linking

Future Plans

• Better deployment tool GUI

• More custom, interactive web visualisers for data

• Service linking & interactivity– More web renderers, e.g. applets & JavaScript, for complex input

– Smoother use of multiple services

• Update technology: – newer versions of JBoss, Tomcat

– Look at newer portals: Jetspeed 2, JBoss Portal

end