function SingletonClass()
{
// demo variable
var names = [];
// instance of the singleton
this.singletonInstance = null;
// Get the instance of the SingletonClass
// If there is no instance in this.singletonInstance, instanciate one
var getInstance = function() {
if (!this.singletonInstance) {
// create a instance
this.singletonInstance = createInstance();
}
// return the instance of the singletonClass
return this.singletonInstance;
}
// function for the creation of the SingletonClass class
var createInstance = function() {
// public methodes
return {
add : function(name) {
names.push(name);
},
names : function() {
return names;
}
}
}
// wen constructed the getInstance is automaticly called and return the SingletonClass instance
return getInstance();
}
var obj1 = new SingletonClass();
obj1.add("Jim");
console.log(obj1.names());
// prints: ["Jim"]
var obj2 = new SingletonClass();
obj2.add("Ralph");
console.log(obj1.names());
// Ralph is added to the singleton instance and there for also acceseble by obj1
// prints: ["Jim", "Ralph"]
console.log(obj2.names());
// prints: ["Jim", "Ralph"]
obj1.add("Bart");
console.log(obj2.names());
// prints: ["Jim", "Ralph", "Bart"]