Reflection as a tool for adaptability of software systems

Effective software evolution needs to be supported by appropriate execution environment. We state that adaptiveness can be also achieved using appropriate adaptive language. Runtime adaptability of aspect-oriented language can be one of the solutions which can help in software evolution, but there are some obstacles which do not allow to easy create a desired solution. Applied language or more languages should be minimal and strongly associated with properties of the software system in any point of its implementation, thus there is the need to change language when it is useful in order to language and program would be evolved together. From the viewpoint of adaptability, we classify software systems as being nonreflexive, introspective and adaptive. Adaptive execution can be supported by adaptive language and by environment, which offers reflective possibilities. One of the candidates for this purpose should be Smalltalk-like environment Squeak, which offers several reflective possibilities.