From Requirements to Monitors by way of Aspects

Using goal driven requirements engineering, requirements are derived from a goal model that captures multiple strategies for satisfying the goals and takes into account environmental constraints on the system. The model is therefore more stable than a conventional requirements document. We present early work in building a system for runtime monitoring of system goals, as part of normal system operation, so that failure to achieve goals caused by changes in the system environment can be detected and acted on. We make use of Hyper/J to separate instrumentation for monitoring from the core code, and to add instrumentation directly to class files, without the need to modify the core class files. We are currently using a peer to peer networking client as a testbed and we present examples based on this program.