Shape类和Vehicle类

w5/ShapeTest.java

@@ -0,0 +1,32 @@
+class Shape {
+    public void draw() {
+        System.out.println("绘制一个图形");
+    }
+}
+
+class Circle extends Shape {
+    @Override
+    public void draw() {
+        System.out.println("绘制圆形 ");
+    }
+}
+
+class Rectangle extends Shape {
+    @Override
+    public void draw() {
+        System.out.println("绘制矩形 ");
+    }
+}
+
+public class ShapeTest {
+    public static void drawShape(Shape s) {
+        s.draw(); 
+    }
+
+    public static void main(String[] args) {
+        Shape circle = new Circle();
+        Shape rect = new Rectangle();
+        drawShape(circle);
+        drawShape(rect);
+    }
+}

w5/VehicleTest.java

@@ -0,0 +1,38 @@
+abstract class Vehicle {
+    public abstract void run();
+}
+
+class Car extends Vehicle {
+    @Override
+    public void run() {
+        System.out.println("汽车在公路上行驶，时速80km/h ");
+    }
+}
+
+class Bike extends Vehicle {
+    @Override
+    public void run() {
+        System.out.println("自行车在非机动车道骑行，时速15km/h ");
+    }
+}
+
+class Truck extends Vehicle {
+    @Override
+    public void run() {
+        System.out.println("卡车在高速上运输货物，时速60km/h ");
+    }
+}
+
+public class VehicleTest {
+    public static void main(String[] args) {
+        Vehicle[] vehicles = {
+            new Car(),
+            new Bike(),
+            new Truck()
+        };
+
+        for (Vehicle v : vehicles) {
+            v.run();
+        }
+    }
+}