Abstract: In the background of components assembly, since the existing software can hardly fulfill changeable requirement of users, the paper proposed an algorithm for component behavior fragment extraction and composition based on logical reasoning. The main idea is based on the researches of interface mapping and state transition of components,which establishes the structural model and state model of component behavior, and breaks down then into component behavior fragments that are derived on the basic of calculus. In the end,following the method of logical reasoning, the paper took the input and output as target solutions,and provided a composite component to meet requirement goals by compositing the useful component behavior fragment from relation derivation.

Key words: Component behavior fragment, calculus, Logical reasoning, Component assembly