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Pranjal Agnihotri
4,187 PointsScanner Class In Java
what does we mean by statement Scanner scanner = new Scanner(System.in); I know that Scanner is a class and we are making its object by name "scanner" but why we are passing System.in (as System is also a class) so can we pass a class as Parameter. AND ONE THING MORE ::: What does we mean by "in" in System.in is it a variable or System is a object so we are calling a member variable.
3 Answers
Wout Ceulemans
17,603 Points"in" is a public static variable. So when you do "System.in" you actually access the public static variable called "in" in the System class.
So if you would do: Scanner scanner = new Scanner(System.in);
You create a new Scanner object, store that into the scanner variable, and as a paramter you pass the public static variable "in" from the System class with it.
Pranjal Agnihotri
4,187 PointsBut In java how can we call a member variable using its class name outside the class . We should make object for that but here System is class
Konstantinos Pedarakis
21,301 PointsHi Pranjal Agnihotri ,
static variables are associated with the class itself. you can call static variables outside of the class even without creating an object of that class. you just need to specify the class name first and then the name of the variable. as "System.in".
Pranjal Agnihotri
4,187 PointsNow I understood , here "in" is a Static variable and we r using System class for its Scope resolution outside class.