随机确定形状是填充还是未填充

Question

我正在尝试创建一个randomShape（）方法，该方法实例化并返回一个随机的Shape对象。我已经解决了大部分问题，我的问题是在我的支持方法getFilledUnfilled（）中。该支撑方法需要随机确定形状是否填充/未填充。以下是我的代码。

import java.awt.*;
import java.util.*;
public class Shape {

//enumerated constants
public static enum Shapes {OVAL, CIRCLE, RECTANGLE, SQUARE}

//instance data variables
protected Color color;
protected boolean isFilled;
protected int width;

//class method
public static Shape randomShape(){
    Shape s = new Shape();
    s.getRandomShapeObject();
    return s;
}//end randomShape()

//service method (blank, to be overridden by subclasses)
public void draw(Graphics g, int x, int y){

}//end draw()

//support methods

private void getRandomShapeObject(){
    ArrayList<Shapes>shapeChoice = new ArrayList<Shapes>();
    Random rand = new Random();
    int size = shapeChoice.size();
    shapeChoice.get(rand.nextInt(size));
}//end getRandomShapeObject()

以下是问题的方法

private void getFilledUnfilled(){
    ArrayList<Shapes>shapeFillUnfill = new ArrayList<Shapes>();
    Random rand = new Random();


}