The idea of a connector

which explicitly describes the interactions among components

is one of the important contributions of the research on software architecture.In this paper

we argue that such an important abstraction deserves first-class support from programming languages.We proposed a new component-oriented programming language SAJ(Software Architecture-based Java)

which integrates some ar chitectural concepts such as the component

the port and particularly the connector into SAJ.The connector is treated as a first-class entity in SAJ as is the component so that software architecture can be made more explicit at implementation level and the simultaneous reuse of the component and the connector can be realized.We formalize our language giving both the type system and operational semantics and show its soundness property.