Golang Single-piece mode

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Single-piece mode singleton

It is to provide a global instance. For example, a database connection, if each user and thread are applied independently, it will soon reach the upper limit of the database connection. The global variable is not used because:

• Some languages have no global variables;

• A global variable cannot prevent a class from being instantiated more than once.

The ultimate goal is to ensure that only one global instance is available, such as through the conventional Instance (), and Instance () guarantees that it will not be created repeatedly. Or you cannot invoke the constructor of the class, but only the get instance function of the class, which makes it impossible to create a new instance.

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Directory structure

Main.go

./singleton/singleton.go

Singleton.go

Package Singletonimport ("FMT") var _self *singletontype Singleton struct {Name string}func Instance () *singleton {if _self = = Nil {_self = new (Singleton) return _self}return _self}func (o *singleton) SetName (s string) {_self. Name = S}func (o *singleton) GetName () {fmt. Println ("Name:", _self. Name)}

Main.go

Package Mainimport ("./singleton") func main () {a: = Singleton. Instance () B: = Singleton. Instance () a.setname ("Funny") b.setname ("Test") A.getname () return}

Results: Name:test