Question

Java定义一个Rectangle类

（1）定义一个Rectangle类，添加两个属性width、height，提供相应的构造方法及成员变量的设置器和访问器。
（2）在Rectangle中添加两个方法分别计算矩形的周长和面积。
（3）定义测试类，创建Rectangle对象，输出一个矩形的周长和面积。

Answer 1

class Rectangle {
	private double width;
	private double height;

	public Rectangle(double width, double height) {
		this.width = width;
		this.height = height;
	}

	public double getC() {
		return (width + height) * 2;
	}

	public double getS() {
		return width * height;
	}

	public double getWidth() {
		return width;
	}

	public void setWidth(double width) {
		this.width = width;
	}

	public double getHeight() {
		return height;
	}

	public void setHeight(double height) {
		this.height = height;
	}
}

public class Test {
	public static void main(String[] args) {
		Rectangle rect = new Rectangle(4, 5);
		System.out.println("周长=" + rect.getC() + "\n面积=" + rect.getS());
	}
}

Answer 2

12345678910111213141516171819202122232425262728293031323334353637383940class Rectangle { private double width; private double height; public Rectangle(double width, double height) { this.width = width; this.height = height; } public double getC() { return (width + height) * 2; } public double getS() { return width * height; } public double getWidth() { return width; } public void setWidth(double width) { this.width = width; } public double getHeight() { return height; } public void setHeight(double height) { this.height = height; }} public class Test { public static void main(String[] args) { Rectangle rect = new Rectangle(4, 5); System.out.println("周长=" + rect.getC() + "\n面积=" + rect.getS()); }}