feat:Shape

w5/Shape.java

@@ -0,0 +1,3 @@
+public abstract class Shape {
+    public abstract void draw();
+}

w5/ShapeCalculator.java

@@ -1,56 +0,0 @@
-package w5;
-
-public class ShapeCalculator {
-    abstract class Shape {
-        public abstract double getArea();
-    }
-    class Circle extends Shape {
-        private double radius;
-        public Circle(double radius) {
-            this.radius = radius;
-        }
-        @Override
-        public double getArea() {
-            return Math.PI * radius * radius;
-        }
-    }
-    class Rectangle extends Shape {
-        private double width;
-        private double height;
-        public Rectangle(double width, double height) {
-            this.width = width;
-            this.height = height;
-        }
-        @Override
-        public double getArea() {
-            return width * height;
-        }
-    }
-    class Triangle extends Shape {
-        private double base;
-        private double height;
-        public Triangle(double base, double height) {
-            this.base = base;
-            this.height = height;
-        }
-        @Override
-        public double getArea() {
-            return 0.5 * base * height;
-        }
-    }
-    class ShapeUtil {
-        public static void printArea(Shape shape) {
-            System.out.println("图形面积为：" + shape.getArea());
-        }
-    }
-    public static void main(String[] args) {
-        ShapeCalculator calculator = new ShapeCalculator();
-        Shape circle = calculator.new Circle(5);
-        Shape rectangle = calculator.new Rectangle(4,6);
-        Shape triangle = calculator.new Triangle(3,8);
-        System.out.println("====== 图形面积计算器 ======");
-        ShapeUtil.printArea(circle);
-        ShapeUtil.printArea(rectangle);
-        ShapeUtil.printArea(triangle);
-    }
-}