Middleware enables distributed components to interact with each other in diverse and complex styles, which increase the occasions of undesired components interactions (UCIs). Such UCIs may cause serious problems, e.g. quality violation, function loss, and even system crash. In this position paper, we present an online approach for detection and resolution of UCIs based on runtime software architecture (RSA), which does three contributions. First, RSA is implemented by reflection which is a powerful and popular mechanism to monitor and control component-based systems at runtime so that UCIs could be detected and resolved online. Second, RSA is a type of software architecture which is a comprehensive and commonly used model for design and analysis of component-based systems and then helps to represent and analyze UCIs and plan corresponding resolutions. Third, RSA can monitor and adapt runtime systems automatically under the guide of well-defined patterns so that fully automatic detection and resolution of UCIs become possible and reusable.