"SEAMLESS APPLICATION" for seamless and personal mobile computing

• Authors: Paul G. Austrem
• Venue: Proceedings of the 14th Conference on Pattern Languages of Programs
• Year: 2007

Mobile information systems are growing in acceptance; in order for the vision of true mobility to be realized users must be able to seamlessly move running applications between devices in an ad-hoc manner. Workers such as journalists, or workers that travel a lot could draw benefit from this. The task of implementing mechanisms to ensure that a running application is successfully moved from one device to another can be considered a generic task, wherein the same fundamental design can be reused. This work presents a high level architectural composite design pattern that resolves the challenges associated with transferring a running application from one device to another whilst maintaining state and tailoring to capabilities. This is accomplished by using a transferable command stack to maintain state and the involved device's implementing an interface exposing their functional profile. This facilitates the adaptation of the command stack to suit the target device, and for new target devices to be added in an ad-hoc manner. The pattern is comprised of three roles which each utilize other design patterns. Additionally the pattern addresses exception scenarios and how they should be handled to keep an application in a consistent state. The solution adds complexity and imposes conventions on the extendibility of a system, but makes it possible for users to maintain state so they can seamlessly move their work between devices.