Abstract
The authors consider a modeling language and simulation environment based on object-oriented principles aimed to help in the design of reactive systems. The language framework includes diagrams of object structure and interconnection, statecharts as a behavior description, and C++ for data objects and functions. Timed transition systems are used as a semantic model. COVERS enables the user to perform the whole modeling-simulation-analysis cycle within a single MS Windows-based graphical environment. They overview the code generation, model execution and visualization of results. The correspondence between the COVERS language and the unified notation is outlined.