The Chain of Responsibility design pattern provides a solution:
Define a chain of Handler objects having the responsibility to either handle a request or forward it to the next handler.
A class sends a request to a chain of handlers
and doesn't know (is independent of) which handler handles the request.
Describing Chain of Responsibility in more detail is the theme of the following sections.
See Applicability section for all problems Chain of Responsibility can solve.

• "The idea of this pattern is to decouple senders and receivers by giving multiple objects a chance to handle a request. The request gets passed along a chain of objects until one of them handles it." [GoF, p223]
• Define and chain Handler objects:
  • Define an interface for handling a request (Handler | handleRequest()).
  • Objects that can handle a request implement the Handler interface by either hand­ling the request directly or forwarding it to the next handler (if any) on the chain.
  • "Chain of Responsibility is a good way to decouple the sender and the receiver if the chain is already part of the system's structure, and one of several objects may be in a position to handle the request." [GoF, p348]
• A class (Sender) sends a request to a chain of handlers (handler.handleRequest()). The request gets passed along the chain until a handler handles it.
• This enables loose coupling between the sender of a request and its receiver(s).
  The object that sends a request has no explicit knowledge of the object (receiver) that ultimately will handle the request.
  The chain of Handler objects can be specified dynamically at run-time (Handler objects can be added to and removed from the chain).