Inheritance in Java (public or private for class fields?)

public class Square {
  public double height;
  public double width;
  public double surfaceArea;

  Square(double height, double width) {
    this.height = height;
    this.width = width;
  }

  public void setHeight(double height) {
    this.height = height;
  }

  public double getHeight() {
    return this.height;
  }

  public void setWidth(double width) {
    this.width = width;
  }

  public double getWidth() {
    return this.width;
  }

  public double computeSurfaceArea() {
    this.surfaceArea = this.height * this.width;
    return this.surfaceArea;
  }

  public double getSurfaceArea() {
    return this.surfaceArea;
  }
}

public class Cube extends Square {
  private int depth = 6;

  Cube(double height, double width) {
    super(height, width);
  }

  public double computeSurfaceArea() {
    super.surfaceArea = (super.height * super.width) * depth;
    return super.surfaceArea;
  }
}

import java.util.Scanner;

public class DemoSquare {
  public static void main(String args[]) {
    Scanner input = new Scanner(System.in);

    Square square;
    Cube cube;

    double doubleValue1, doubleValue2;

    System.out.print("Enter value for height: \n>> ");
    doubleValue1 = input.nextDouble();

    System.out.print("Enter value for width: \n>> ");
    doubleValue2 = input.nextDouble();

    square = new Square(doubleValue1, doubleValue2);
    cube = new Cube(doubleValue1, doubleValue2);

    System.out.println("\n<Results>\n");
    System.out.println("Surface area of <Square Class>: " + square.computeSurfaceArea());
    System.out.println("Surface area of <Cube Class>: " + cube.computeSurfaceArea());
  }
}

Is it okay if I make my class fields(Parent class) to public rather than private? It's because im using the concept of inheritance right here. Or should I use the getters/setters method in the parent class.

via Sean