Chapter 6

Exceptions, Actor Termination, and Shutdown

In this chapter, we will look at how to handle errors in concurrent, actor-based programs. Actors provide several additional ways to handle exceptions compared to sequential Scala code. In particular, we will show how an actor can handle exceptions that are thrown but not handled by other actors. More generally, we will look at ways in which an actor can monitor other actors to detect whether they terminated normally or abnormally (for instance, through an unhandled exception). Finally, we introduce several concepts and techniques that can simplify termination management of actor-based programs.