Code on a screen

Observer – A Tool for State Management

Introduction

 This is the second in our Software Design Pattern series of posts and today we are going to take a look at the Observer pattern.  The formal intent of the Observer Pattern as defined in the GOF Design Pattern book is, “Define a one-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically.”  This pattern is actually used quite often, for example when you create a listener on an element in JavaScript for when that element is clicked.  Anytime you have a situation where one object needs to know when another object’s state changes, you can use the Observer pattern.

orange fractual

Singleton – Pattern or Anti-Pattern?

Introduction

Patterns are interesting to me.  You can observe patterns almost wherever you look.  Where you see a repeated pattern it seems obvious that some sort of thinking has gone into what you’re observing.  Patterns imply design and design implies a designer.  As a Christian this has great meaning for me because the design that is observed in creation such as the Fibonacci sequence points to a designer that had purpose in the way this world was made.  This is much like software design.  A good software solution always results from a very intentional and skilled software engineer thinking about the way the software should be written and then building the solution accordingly.  Software solutions do not just happen, a designer must make choices and follow best practices to build something that solves the problem that is being addressed.