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Aditya Puri
1,080 PointsHow is "System" a object?
At 0:31 Craig says- "We have already seen how methods can be called on objects like System, console etc.."
Now I understand that "console" is an object, it is an instance of the class Console.
But how is "System" an object? We use the static method "exit" on the class "System" itself without making an instance of the class. Then why does he call "System" an object? Shouldn't it be a class??
3 Answers
Marina Alenskaja
9,320 Points"The System class contains several useful class fields and methods. It cannot be instantiated." - https://docs.oracle.com/javase/7/docs/api/java/lang/System.html
Alexander Nikiforov
Java Web Development Techdegree Graduate 22,175 PointsSystem is a Class but as every Class in Java inherits java.lang.Object.
So System is a Class and if you go to definition of Systemthere is invisible line ... class System extends Object
And no System class cannot be instantiated, because, see here:
http://stackoverflow.com/questions/12392888/why-system-class-cannot-be-instantiated
From answers there: It cannot be instantiated because "it has a private constructor" and "only is a bunch of static methods and properties."
Aditya Puri
1,080 PointsAditya Puri
1,080 PointsSo the "System" class is both an object and a class? As we cannot create its instances??