For every user interaction provided by a GUI component, an instrumentation is required (by the component developer) that allows the application developer to specify whether this user interaction serves as the start or stop of a user transaction of the developed application. In addition, the application developer needs a means to uniquely (within the application) name the user transaction to be started. In our approach this is done during component customization, which essentially means configuring a component's parameters (e.g., via the GUI of the development environment) during application development.
Similarly, so-called active components require special treatment. By active components we mean components which have a queue and a control flow of their own. These components require an initiatedTA-call whenever a task is placed into the queue as well as startSTA- and stopSTA-calls respectively surrounding the processing of the task.