Java Point，getX() 和 point.x 的区别
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Java Point, difference between getX() and point.x
提问by James Fazio
I am confused to as why the Java Point class takes in two int paramaters and the getX() and getY() methods return doubles. For example I could define a Point
我很困惑，为什么 Java Point 类接受两个 int 参数，而 getX() 和 getY() 方法返回双精度值。例如我可以定义一个 Point
Point p = new Point(4,6);
If I were to call..
如果我打电话..
p.getX();
It would return 4.0. and if I were to call
它将返回 4.0。如果我打电话
p.x;
I would get 4.
我会得到 4。
Any reason for this?
这有什么原因吗？
采纳答案by trutheality
There are Point2D.Doubleand Point2D.Floatclasses that extend Point2Dwhich is a superclass of Pointand they need to be able to work with floating point values. Note that there is also a setLocation( double, double ).
有Point2D.Double和Point2D.Float扩展类Point2D是一个超类Point，他们需要能够将工作与浮点值。请注意，还有一个setLocation( double, double ).
Point2Dis an abstract class that implements the distance calculation for points, and setLocation, getX, and getYare its abstract methods, which is why they all use doublesand why Pointhas to implement them with doubles in the signature.
Point2D是一个抽象类，它实现的距离计算点，和setLocation，getX和getY是它的抽象方法，这就是为什么他们都用doubles，为什么Point有执行这些doubleS IN的签名。
