In this program, we will java Program see how to calculate the area of a circle when the radius is given.
java 点到圆的距离 java求圆的半径,classCircle{doubleradius;//圆的半径默认值是0.0//定义一个获取面积的方法publicdoublegetArea(){return3.14*radius*radius;}}pub
使用该Circle类的示例代码如下: public class Main { public static void main(String[] args) { Circle circle = new Circle(5.0); System.out.println("圆的半径为:" + circle.getRadius()); System.out.println("圆的面积为:" + circle.getArea()); circle.setRadius(7.0); System.out.println("修改...
private double radius=1; public Circle() { } public Circle(double radius) { this.radius = radius; } public void setRadius(double radius) { this.radius = radius; } public double getRadius() { return radius; } public double getArea() { return Math.PI*radius*radius; } public double get...
C:\Program Files (x86)\Common Files\Oracle\Java\javapath所以没有手动配置环境变量时,java 命令可以用,但 javac 不行。 每次改动,都需要重新打开 DOS 窗口,配置才能生效。输入 javac Hello.java,如果你的语法正确,就会在当前路径下生成 class(字节码)文件,再输入 java Hello ,此时别带后缀。有...
(1)定义一个Circle类,包含一个double型的radius属性代表圆的半径,一个findArea()方法返回圆的面积。 (2)定义一个类PassObject,在类中定义一个方法printAreas(),该方法的定义如下:publicvoidprintAreas(Cirlce c,inttimes) 在printAreas方法中打印输出1到time之间的每个整数半径值,以及对应的面积。例如,times为5,...
sealed interface Shape permits Rectangle, Circle {} record Rectangle(Point topLeft, Point bottomRight) implements Shape {} record Circle(Point center, int radius) implements Shape {}In jshell, create the following printShapeInfo(Shape shape) method, which prints different information depending on the...
sealed interface Shape permits Circle, Square { } record Circle(double radius) { } record Square(double length) { } There are other features that come in really handy (and they are being worked on and one even previews in Java 21—more on that later), but these are the basics, and Ja...
Circle类: import java.lang.Math; public class Circle { // 圆半径 private double radius; // 构造方法,半径置零 public Circle(){ radius=0; } // 构造方法,创建Circle对象时将半径初始化为r public Circle(double r){ radius=r; } // 获得圆半径 public double getRadius(){ return radius; } /...
SimpleCircle circle = new SimpleCircle();表示调用这个类 circle.radius;表示调用这个类中定义的值,分号前面加括号表示调用这个类定义的方法 SimpleCircle circle = new SimpleCircle(25);这个还有一层意思就是调用这个类的构造方法,也就是用这个类名命名的方法 可以看到这个类的构造方法是这么写的 Simp...