Static Class and Its Usage in Java Example Program


Static Class (Nested) Characteristics In Java

  • A static class can access without creating any of object If it has static data members and methods.
  • A static class cannot access non-static data members and methods. 
  • The static class can be accessed by outer class name.
  • Need to create an object for access non-static data members and methods. 
  • A static class created inside a class is called nested static class. 
  • Only nested classes can be static classes.
  • In Java, we can declare a class within another class. It is called a nested class. That nested class accessed based on Outer class.

Syntax

//Static Class
static class className(){
	//Do something
}

//Static variable
static int variableName = 0;

//Static method inside a static class
static class className(){
	static void staticMethod(){
		//Do something
	}
}

Static Class Example Program 

class StaticClass {
    
    public static class StaticClassInner {
    public static int staticNumber = 100;
    
    public static int staticMethod() {
        staticNumber = 200;
        return staticNumber;
    }
}
    
    public static void main(String []args){
        System.out.println("Initial value of Static number : " + StaticClassInner.staticNumber);
        System.out.println("Static number inside static class : " + StaticClassInner.staticMethod());
     }
}

Sample Output

Initial value of Static number : 100
Static number inside static class : 200