square.java

来自「Java程序设计大学教程程序源代码」· Java 代码 · 共 17 行

package jbookch4;

public class Square extends Retangle {
    public Square(double side) {
        super(side,side);
    }

    public double calcPerimeter() {
        return length * 4;
    }

    public String toString() {
        return "边长为" + length + "的正方形";
    }

}