用java编程语言实现

Question

写一个名为Rectangle的类表示矩形。其属性包括宽width和高height颜色color，width和height都是double型的。要求该类具有：使用getter和setter的形式完成属性的访问及修改；提供计算面积的getArea()方法 。

Answer 1

初学者呀，死去的大二知识来了

public class Rectangle {
    private double width;
    private double height;
    private String color;

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

    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 String getColor() {
        return color;
    }

    public void setColor(String color) {
        this.color = color;
    }

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

上述代码定义了一个Rectangle类，具有三个属性：width、height和color，分别表示矩形的宽、高和颜色；还有一个构造方法、六个访问和修改属性的getter和setter方法，以及一个计算矩形面积的getArea()方法。

使用时可以先实例化一个Rectangle对象，然后通过getter和setter方法访问和修改其属性，最后调用getArea()方法计算矩形面积。例如：

Rectangle rect = new Rectangle(2.5, 3.1, "red");
System.out.println("Width is: " + rect.getWidth());
System.out.println("Height is: " + rect.getHeight());
System.out.println("Color is: " + rect.getColor());
System.out.println("Area is: " + rect.getArea());

rect.setColor("blue");
System.out.println("New color is: " + rect.getColor());

rect.setWidth(4.3);
rect.setHeight(5.6);
System.out.println("New area is: " + rect.getArea());

Answer 2

定义Rectangle类，定义属性和计算面积的方法，代码如下：

public class Rectangle {  
    private double width;  
    private double height;  
    private String color;  
  
    public Rectangle(double width, double height, String color) {  
        this.width = width;  
        this.height = height;  
        this.color = color;  
    }  
  
    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 String getColor() {  
        return color;  
    }  
  
    public void setColor(String color) {  
        this.color = color;  
    }  
  
    public double getArea() {  
        return width * height;  
    }  
}

定义主函数，调用Rectangle类，代码如下：

public class Main {  
    public static void main(String[] args) {  
        Rectangle rectangle = new Rectangle(5.0, 3.0, "red");  
        System.out.println("Width: " + rectangle.getWidth());  
        System.out.println("Height: " + rectangle.getHeight());  
        System.out.println("Color: " + rectangle.getColor());  
        System.out.println("Area: " + rectangle.getArea());  
    }  
}

运行结果：