给定圆半径，JAVA打印近似圆

public class Circle{

private int radius;

private void printCircle(){

for (int i = 0-radius; i <= radius ; i++){
//算出x的坐标
double x = Math.sqrt(radius * radius - i * i);
long xZheng = Math.round(x);
//画出(xZheng,y)对应的点,与空格
//宽与高的比是2
for(int j = 0-2 * radius ; j <= 2 * radius ; j++){
if(Math.abs(j) == 2 * xZheng){
System.out.print("*");
}
else{
System.out.print(" ");
}
}
System.out.println();
}
}

public static void main(String[] args){
Circle c = new Circle();
c.radius = 6;
c.printCircle();
}
}