Example constant and Variable

Constant

public class MainClass {

  public static void main(String[] arg) {

    final int FEET_PER_YARD = 3;          // Constant values

    final double MM_PER_INCH = 25.4;      // that cannot be changed

    System.out.println(FEET_PER_YARD);

    System.out.println(MM_PER_INCH);

   

  }

}

Variable

public class MainClass {

  public static void main(String args[]) {

    double a = 3.0, b = 4.0;

    // c is dynamically initialized

    double c = Math.sqrt(a * a + b * b);

    System.out.println("Hypotenuse is " + c);

  }

}