From Corrib Clan Wiki

Contents 1 Current MarcOnt portal architecture 1.1 Advantages: 1.2 Drawbacks: 1.3 Layercake architecture overview 2 Suggested MarcOnt portal architecture 2.1 Advantages: 2.2 Drawbacks: 2.3 Layercake architecture overview 3 Existing software

Current MarcOnt portal architecture

• thin client – all actions performed on the server side
• only use of JSF
• no use of java web services or any other java technologies
• no client application – access via web browser

Advantages:

• no need to install java runtime environment or any other software (but only gives limited functionality because some tasks – i.e. graph display – require JRE)

Drawbacks:

• high server traffic (caused by many server requests) causes slow work
• no possibility to work off-line
• heavy ontologies may cause server timeouts
• no possibility of caching ontologies while editing (in case of i.e. connection loss or other random accidents all changes are lost)
• despite using JSF no pure MVC (model-view-control) paradigm achieved
• GUI building time consuming
• GUI errors cause application to stop
• GUI functionality limited by web browser usage
• using JSF causes no XHTML compliance, application is likely not to work on MAC Safari browser

Layercake architecture overview

Suggested MarcOnt portal architecture

• rich client – a hybrid approach
• versioning managed by server as it is implemented now
• editing managed by 2 java web start applications (one for ontology editing, the other for rules generation)
• java web start application is downloaded by a user only during first usage, resides in the system and can be launched or removed at any time later also off-line)
• use of JSF, java web start, java web services
• dedicated client application

Advantages:

• limited server traffic to only necessary versioning actions
• possibility to work on ontology and mapping rules off-line
• caching of ontologies on a client machine
• MVC paradigm achieved by using visual GUI builders
• faster GUI building
• no GUI errors
• GUI functionality only limited by possibilities of SWING applications
• using web services makes it easier for other people to create independent tools or plugins for ontology development

Drawbacks:

• requirement to install Java Runtime Environment (but it is available for every graphical environment, is very widely used, many people have it already installed)
• requirement to download client applications during first usage – for modem connection users may last quite long (the applications will contain Jena classes, so the size of the application can be up to 10MB)

Layercake architecture overview

Existing software

• Protege is a J2SE desktop application that can be used offline, but is difficult to use. There is a possibility of writing a collaborative work plugin to it but since the whole is hard to use it would not be used by wide audience.
• SWOOP is a J2SE desktop application its main goal is to be user friendly. It can be used using Java WebStart: http://www.mindswap.org/2004/SWOOP/Swoop.jnlp.