Formally Composing Components in Product Line Context

Components composition is core techniques of software product line, which can promote reuse of components. Variability exists in components and components composition in SPL context, which bring new challenges to tradition components composition techniques. vADL can formally describes SPL architectures, and also supports layered components compositions. The paper provides systemic methods for components compositions with vADL. Techniques of variability points binding, constrains assembly, guard condition restrict are presented in detail, which can assemble variability of components. Behavior assembly technique also be described, which utilize parallel combined mechanism of n-calculus. Variability in structure assembly, ports assembly and behavior assembly also is discussed. In order to sure correctness and consistency, some analysis methods for components composition also are provided.