JWire Concepts

AComposite

foo : Foo bar : Bar

Components are Java objects.

Components play roles in one or more interaction protocols. Roles are named and typed.

out : Requirement<Input>

in : Input

Systems are created by instantiating components and “wiring” their roles together. New component types can

be defined as compositions of existing components.

Meta-level Descriptors

adaptiondescrip tor

b ind ingdescrip tor

com ponentdescrip tor

com ponentdescrip tor

ro ledescrip tors

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Descriptors are per instance not per class (c.f. Java Beans)

Composition “Recipes”

• To place components, ALAN run-time must know their resource requirements.

• How?– Add this information to the descriptors

• Create descriptors first:– Descriptors encapsulate how to create

components and bind them– Act as “recipes” for a configuration

What For?

• Automatic creation of distributed app’s– User’s applications generates recipes

• E.g. for searching, purchasing, negotiating, etc.

– Pass recipe to ALAN services– ALAN deploys components in optimal

locations around network

• Mobile agents “done right”– Concurrency, distribution, efficiency