What are the advantages of the delegate pattern over the observer pattern?

Posted by JoJo on Programmers See other posts from Programmers or by JoJo
Published on 2012-12-02T00:06:55Z Indexed on 2012/12/02 5:21 UTC
Read the original article Hit count: 352

Filed under:

design-patterns

|

delegates

|

observer-pattern

In the delegate pattern, only one object can directly listen to another object's events. In the observer pattern, any number of objects can listen to a particular object's events. When designing a class that needs to notify other object(s) of events, why would you ever use the delegate pattern over the observer pattern? I see the observer pattern as more flexible. You may only have one observer now, but a future design may require multiple observers.

© Programmers or respective owner

Related posts about design-patterns

Should universities put more emphasis on teaching their students about design patterns?

as seen on Programmers - Search for 'Programmers'
While I've heard about design patterns being mentioned in a few courses at uni, I know of only a single course which actually teaches design patterns. In almost all other areas (algorithms, parallelism, architecture, dynamic languages, paradigms, etc), there are several, often a basic course and an… >>> More
Podcasts on GoF design patterns

as seen on Stack Overflow - Search for 'Stack Overflow'
Anyone know of a good podcast on design patterns? >>> More
How often are design patterns used in the workplace using PHP

as seen on Stack Overflow - Search for 'Stack Overflow'
Hey everyone, I read a book awhile back called PHP Design Patterns and Practice, and ever since then I have been using design patterns whenever I think they are needed. However it just occurred to me that maybe most companies do not use design patterns very often for PHP, or at all. What I was wondering… >>> More
Who benefits from the use of Design Patterns?

as seen on DotNetBlocks - Search for 'DotNetBlocks'
Who benefits from the use of design patterns is like asking who benefits from clean air or a good education. All of the stakeholders of a project benefit from the use of design patterns. Project Sponsor Project sponsors benefit from the use of design patterns because they promote reduced development… >>> More
Architect: "Collaborating on Design Patterns"

as seen on Oracle Technology Network - Search for 'Oracle Technology Network'
It takes an architect community to raise a collection of SOA design patterns. >>> More

Related posts about delegates

Multicast delegates in c#

as seen on ASP.net Weblogs - Search for 'ASP.net Weblogs'
In yesterday’s post We learn about Delegates and how we can use delegates in C#. In today’s blog post we are going to learn about Multicast delegates. What is Multicast Delegates? As we all know we can assign methods as object to delegate and later on we can call that method with the help delegates… >>> More
Delegates and Events in C#

as seen on ASP.net Weblogs - Search for 'ASP.net Weblogs'
Events and their underlying mechanism "Delegates" are very powerful tools of a developer and Event Driven Programming is one of the main Programming Paradigms. Its wiki definition is "event-driven programming or event-based programming is a programming paradigm in which the flow of the program… >>> More
Delegates in c#

as seen on ASP.net Weblogs - Search for 'ASP.net Weblogs'
I have used delegates in my programming since C# 2.0. But I have seen there are lots of confusion going on with delegates so I have decided to blog about it. In this blog I will explain about delegate basics and use of delegates in C#. What is delegate? We can say a delegate is a type safe function… >>> More
Delegates in .NET: how are they constructed ?

as seen on Stack Overflow - Search for 'Stack Overflow'
While inspecting delegates in C# and .NET in general, I noticed some interesting facts: Creating a delegate in C# creates a class derived from MulticastDelegate with a constructor: .method public hidebysig specialname rtspecialname instance void .ctor(object 'object', native int 'method') runtime… >>> More
Why not .NET-style delegates rather than closures in Java?

as seen on Stack Overflow - Search for 'Stack Overflow'
OK, this is going to be my beating a dying horse for the 3rd time. However, this question is different from my earlier two about closures/delegates, which asks about plans for delegates and what are the projected specs and implementation for closures. This question is about - why is the Java community… >>> More