编写一个JAVA程序，描写一个矩形类，并输出某个矩形的长，宽，面积。具体描述如下？

// 矩形

public class RectangleDemo {

public static void main(String[] args) {

RectangleDemo demo = new RectangleDemo(12, 32)

System.out.println(demo.getPerimeter())

System.out.println(demo.getArea())

demo = new RectangleDemo()

System.out.println(demo.getArea())

System.out.println(demo.getPerimeter())

demo.setHeight(50)

demo.setWidth(30)

System.out.println(demo.getArea())

System.out.println(demo.getPerimeter())

}

// 求周

public double getPerimeter() {

return (height + width) * 2

}

// 求面积

public double getArea() {

return height * width

}

public RectangleDemo(double height, double width) {

this.height = height

this.width = width

}

public RectangleDemo() {

this.height = 10

this.width = 10

}

private double height// 高纯盯度

private double width// 宽度

public double getHeight() {

return height

}

public void setHeight(double height) {

this.height = height

}

public double getWidth() {

return width

}

public void setWidth(double width) {

this.width = width

}

}

编写矩做拦和形类RectangleJava程序矩形类两数据员别rLength宽rWidth通getLength()、getWidth()、getArea()别查看矩形、宽面积通setLength()setWidth()重新设置矩形宽衡丛

public class RectangleDemo {

private static int M = 20

private static int N = 18

private int m// 长度

private int n// 宽度

RectangleDemo(int m, int n) {

if (m >0) this.m = m

else this.m = M

if (n >0) this.n = n

else this.n = N

}

public void print() {

for (int i = 0i <ni++) {

if (i == 0 || i == n - 1) {

for (int j = 0j <mj++) {

if (j == 0 || j == m - 1)

System.out.print("|")

else

System.out.print("-")

}

} else {

for (int j = 0j <mj++) {

if (j == 0 || j == m - 1)

System.out.print("|")

else

System.out.print(" ")

}

}

System.out.println()

}

}

public static void main(String[] a) {

RectangleDemo re = new RectangleDemo(20, 8)

re.print()

}

}

结果

要想者颂以‘*’为边 把袭游输出改成 * 就可以拍嫌销了

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