Customizing component-based architectures by contract

This paper presents an approach to describe, deploy and manage component-based applications having dynamic functional and non-functional requirements. The approach is centered on architectural descriptions and associated high-level contracts. The latter allow the nonfunctional requirements to be described separately at design time, and during the running time are used to guide architecture customizations required to enforce these requirements. This helps to achieve separation of concerns, facilitating the reuse of modules that implement the application in other systems. The infrastructure required to manage the contracts follows an architectural pattern, which can be directly mapped to specific components included in a supporting reflective middleware. This feature allows designers to write a contract and to follow a standard recipe to insert the extra code required to its enforcement in the supporting middleware.