Chain of Responsibility

Chain of responsibility is about splitting one large task with sequential and complicated requirements into non-overlapping handlers.

CoR suggests that these /handlers should be linked into a chain, where each handler has a field storing a reference to the next handler.

In addition to processing the request, handlers should pass the request further to next handler. Moreover, handlers can decide not to pass the request and thus stop further processing. An example for this could be authentication, that failure in any part should remark the failure of whole procedure.

Another version of CoR is that, handlers check if they can process it, if yes, then ends here; otherwise, the request will be passed further. A typical scenario is UI interaction.