> > a useful feature for *any* iterative algorithm would be the > > possibility to call a "monitor" at the end of each iteration. What > > would this monitor do would pretty much depend on the user's mood: > > periodically backup the state of the algorithm (in order to restart it > > in case of a crash), log a set of tabulated values (to plot the > > convergence of the algorithm), ... > > The idea would be to come up with a design as general as possible. > > Gilles proposed (see MATH-581) to use java.util.Observable. This > > sounds very attractive to me. Any comments? > > +1 to the idea of using the Observer pattern; but -0 for > Observable. I would favor defining Events and Listeners because a) > Observable is concrete, so effectively forces you to create an > Observable delegate and b) the interface is crude and is really > designed for GUI scenarios where observers are holding references to > the Observable and just being notified that something has changed.
Indeed, that would be all that is necessary for a simple home-made monitoring solution. I fear that a more complex functionality would entail reinventing the wheel. > Events are more flexible and can be implemented using interfaces. > Has anyone ever actually used Observable outside of a GUI m/v > environment? Hmm, that would be me. > Does anyone know of event frameworks suitable for > monitoring long-running computations that we might adapt? I must raise the issue again: s/adapt/use/ > In any case, I think it is a good idea to develop an event framework > for [math]. We should probably also think about doing this in a way > that is at least JMX-friendly. I don't know anything about JMX. Gilles --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
