單例類合是,確保應用運行的整個過程委造,通過該初始化方式得到的都是同一個對象缚窿!
/*:
?? Singleton
------------
The singleton pattern ensures that only one object of a particular class is ever created.
All further references to objects of the singleton class refer to the same underlying instance.
There are very few applications, do not overuse this pattern!
### Example:
*/
class DeathStarSuperlaser {
static let sharedInstance = DeathStarSuperlaser()
private init() {
// Private initialization to ensure just one instance is created.
}
}
/*:
### Usage:
*/
let laser = DeathStarSuperlaser.sharedInstance