Where exactly the Singleton Pattern is used in real application?

Question

I was just curious where exactly the singleton pattern is used... I know how the pattern works and where it can be used but i personally never used in any real application. Can

Answer 1

I used the singleton pattern in an online Football Team Store System. we applied the singleton pattern to a ShoppingCart class.

You only needed one instance of the cart per an application instance. so the singleton seemed like it's the best fit for that situation.

Answer 2

Singleton Pattern can be used for loading the configuration , say in a web application, we are supposed to generate a file which is to be stored somewhere in the server. Now, that location can fetched from a config file(properties file) using a singleton class.since the location is to be unique and might change frequently in future, so we use a config file so as can be modified without deploying the application so as to reflect the changes and location will be global and unique through out the application

Answer 3

I used a singleton (actually a couple of them) in an application that used pureMVC. We were unhappy about the complexity this framework introduced (it became complicated and tiering to track method calls through the mvc layers). So we used a central singleton as a mediator to better separate the layers from each other.

Answer 4

Some examples:

• Hardware access
• Database connections
• Config files

Answer 5

For example running a trial version of a software with one license and one database connection ,that uses singleton pattern in real word. may be the guru jon skeet can provide example like this.

Answer 6

I use a media player in my android app, so I extend the mediaplayer class, and used the singleton pattern because I need only one instance, and be able to call the same instance in any other part of my app for check if is playing, or what file is current playing.

Hope it helps you, regards!!!!