Btukfyl

I want to use some object of one class and use in other class,but i can not
for example :
class 1:

public class Value {



    private double radious;

    private double lenght;

    public void setRadious(double radious) {

        this.radious = radious;

    }

    public void setLenght(double lenght) {

        this.lenght = lenght;

    }

}

question : how can I use just radious of class 1 in class 2???

class 2:

public class calculateArea

{



    private Value value;

    public double area()

    {

    return 3.14*radious*radious;

    }

}

Create getters for both the values and access them in your second class.

Something like

public double getRadious() {

    return this.radious;

}

public double getLenght() {

    return this.lenght;

}

When working on OOP, ask yourself what code goes where and how many classes you have to make?
For your scenario, you can use aggregation or composition which is to declare the object of one class in another and then you can call the methods of the declared object using dot notation with getter setter methods. So it will go like this.

public class Value 

{       

        private double radious;

        private double lenght;



        public void setRadious(double radious) 

        {

            this.radious = radious;

        }

        public double getRadious() {

            return this.radious;

        }

        public double getLenght() {

            return this.lenght;

        }

        public void setLenght(double lenght)

        {

            this.lenght = lenght;

        }

}







Class # 2

public class calculateArea

{



    private Value value = new Value();



    public calculateArea(double rad) {

         value.setRadius(rad);

    }



    public double area()

    {

        return 3.14*value.getRadious()*value.getRadious();

    }

}

Also, you need to set the value of radius before using it.

Make a getter Method for radious:

public double getRadious(){

  return radious;

}

In the "Main Class":

Value v = new Value();

v.setRadious(2.5);/*Set the Radious value*/



public double area()

{

  return 3.14*v.getRadious()*v.getRadious();

 }

Add getters to class Value.

public class Value {



public double radious;

public double lenght;

public void setRadious(double radious) {

    this.radious = radious;

}

public void setLenght(double lenght) {

    this.lenght = lenght;

}

public double getLenght() {

    return this.lenght;

}

public double getRadious() {

    return this.radious;

}



}

Make an instance of class 1

public class calculateArea{



public Value;

calculateArea(){

value = new Value();

}



public double area(){

value.setRadious(2.34);//or set ACCORDINGLY

return 3.14 * value.radious * value.radious;

}

}

Declare getters and setters for Value-class:

public class Value {

 private double radious;

 private double lenght;



 public Value(double radious, double length) {

   this.radious = radious;

   this.length = length;

 }



 public void setRadious(double radious) {

   this.radious = radious;

 }

 public void setLenght(double lenght) {

   this.lenght = lenght;

 }

 public double getRadious() {

  return this.radious;

 }

 public double getLength() {

  return this.length;

 }

}

Instantiate the object with some variables:
Value value = new Value(2.0,3.0);

Add Constructor to CalculateArea class:

public class calculateArea {



  private Value value;



  public calculateArea(Value value) {

    this.value = value;

  }



  public double area()

  {

     return 3.14*value.getRadious()*value.getRadious();

  }

}

Instantiate:

calculateArea cArea= new calculateArea(value);

And print result to console in main() method:

System.out.println(cArea.area());