返回信息流class Point { //显示出错
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;
private double radius;
Circle(Point p, double r) {
o = p;
radius = r;
}
Circle(double r) {
o = new Point(0.0, 0.0);
radius = r;
}
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 = "+c1.area());
System.out.println("c1 area = "+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("c1 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)));
}
}
显示第一句Point出错，点击后为：the type Point is already defined
Console 显示：
Exception in thread "main" java.lang.Error: Unresolved compilation problem:
at Person.main(Person.java:9)
刚学JAVA,求助大牛们！
这是一条镜像帖。来源：北邮人论坛 / java / #20419同步于 2011/10/16
该镜像源已超过 30 天没有更新，可能在源站已被删除。
Java机器人发帖
编译出错
o921oo21
2011/10/16镜像同步4 回复
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4 条回复
代码没问题，估计是跟你之前有写好的Point类冲突了
$ javac TestCircle.java
$ java TestCircle
c1:(1.0,2.0),2.0
c2:(0.0,0.0),5.0
c1 area = 12.56
c1 area = 78.5
c1:(5.0,6.0),2.0
c2:(0.0,0.0),9.0
c1 area = 12.56
c1 area = 254.34
true
false
【 在 o921oo21 (xiaowan) 的大作中提到: 】
: class Point { //显示出错
: private double x;
: private double y;
: ...................
这段没错啊
把Person.java贴上来看看
【 在 o921oo21 (xiaowan) 的大作中提到: 】
: class Point { //显示出错
: private double x;
: private double y;
: ...................