How to pass in value with parameters for constructors?

[sara]

[sara]

The constructors can also have parameters. Usually the parameters are used to set the initial states of the object.

Syntax

Syntax for Java Constructor Parameters

class ClassName{

   ClassName(parameterType variable,parameterType2 variable2,...){ // constructor
    ...
   }
}

Example

In the the following demo code Rectangle class uses the parameters, w for width and h for height, from the constructors to initialize its width and height.

class Rectangle {
  double width;
  double height;

  Rectangle(double w, double h) {
    width = w;
    height = h;
  }

  double area() {
    return width * height;
  }
}

public class Main {
  public static void main(String args[]) {
    Rectangle mybox1 = new Rectangle(10, 20);
    double area;
    area = mybox1.area();
    System.out.println("Area is " + area);
  }
}