Answer is :No

Outer classes cannot be static, but nested/inner classes can be. That basically helps you to use the nested/inner class without creating an instance of the outer class. Java has static methods that are associated with classes (e.g. java.lang.Math has only static methods), but the class itself is not static.

If you want to add static class functionality to top level class then follow below steps:

Java has static nested classes but it sounds like you’re looking for a top-level static class. Java has no way of making a top-level class static but you can simulate a static class like this:

  • Declare your class final – Prevents extension of the class since extending a static class makes no sense
  • Make the constructor private – Prevents instantiation by client code as it makes no sense to instantiate a static class
  • Make all the members and functions of the class static – Since the class cannot be instantiated no instance methods can be called or instance fields accessed
  • Note that the compiler will not prevent you from declaring an instance (non-static) member. The issue will only show up if you attempt to call the instance member.
public class TestMyStaticClass {
     public static void main(String []args){
        MyStaticClass.setMyStaticMember(5);
        System.out.println("Static value: " + MyStaticClass.getMyStaticMember());
        System.out.println("Value squared: " + MyStaticClass.squareMyStaticMember());
        // MyStaticClass x = new MyStaticClass(); // results in compile time error
     }
}

// A top-level Java class mimicking static class behavior
public final class MyStaticClass {
    private MyStaticClass () { // private constructor
        myStaticMember = 1;
    }
    private static int myStaticMember;
    public static void setMyStaticMember(int val) {
        myStaticMember = val;
    }
    public static int getMyStaticMember() {
        return myStaticMember;
    }
    public static int squareMyStaticMember() {
        return myStaticMember * myStaticMember;
    }
}

What good are static classes? 
A good use of a static class is in defining one-off, utility and/or library classes where instantiation would not make sense. A great example is the Math class that contains some mathematical constants such as PI and E and simply provides mathematical calculations. 
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