菜鸟技术问题
class Point{
	private double x;
	private double y;
	Point ( double x1, double y1 ){
		x = x1;
		y = y1;
		}
		public double getX(){ return x;}
		public double getY(){ return y;}
		public void setX( double i ){ x = i; }
		public void setY( double i ){ y = i; }		
	}
class Circle{
	private Point o;//复用
	private double radius;
	Circle (Point p, double r){
		o = p;
		radius = r;
		}
		/*圆心定在原点上*/
	Circle (double r){
		o = new Point( 0.0,0.0);//圆心定在原点
		radius = r;
		}	//重载
	boolean contains(Point p){
		double x = p.getX() - o.getX();
		double y = p.getY() - o.getY();
		if ( x*x + y*y > radius*radius) return false;
		else return true;
		}
	public void setO( double x, double y){
		o.setX(x);
		o.setY(y);		
		}
	public Point getO(){ return o;}
	public double getRadius(){return radius;}
	public void setRadius(double r) {radius = r;}
	public double area(){
		return 3.14 * radius * radius;
		}
	}	
	public class TestCircle{
		public static void main(String[] args){
			Circle c1 = new Circle(new Point(1.0,2.0),2.0);
			Circle c2 = new Circle(5.0);
			System.out.println("c1:("+c1.getO().getX()+","+c1.getO.getY()+"),"+c1.getRadius());
			System.out.println("c2:("+c2.getO().getX()+","+c2.getO.getY()+"),"+c2.getRadius());
			System.out.println("c1 Area is " +c1.area());
			System.out.println("c2 Area is " +c2.area());
			c1.setO(5,6);
			c2.setRadius(9.0);
			System.out.println("c1:("+c1.getO().getX()+","+c1.getO().getY()+"),"+c1.getRadius());
			System.out.println("c2:("+c2.getO().getX()+","+c2.getO().getY()+"),"+c2.getRadius());
			System.out.println("c1 area = " +c1.area());
			System.out.println("c2 area = "  +c2.area());
			Point p1 = new Point(5.2, 6.3);
			System.out.println(c1.contains(p1));
			System.out.println(c1.contains(new Point(10.0, 9.0)));  
			}
		}
	结果
D:\java1>javac TestCircle.java
TestCircle.java:48: 找不到符号
符号: 变量 getO
位置: 类 Circle
                         System.out.println("c1:("+c1.getO().getX()+","+c1.getO.g
etY()+"),"+c1.getRadius());
                                                                          ^
TestCircle.java:49: 找不到符号
符号: 变量 getO
位置: 类 Circle
                         System.out.println("c2:("+c2.getO().getX()+","+c2.getO.g
etY()+"),"+c2.getRadius());
                                                                          ^
2 错误
D:\java1>
请问怎么回事啊 我已经定义方法了!
------解决方案--------------------在Circle 和Point 类前面加   static     必须是静态的才行  
static class Circle  
static class Point