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44 lines
1.1 KiB
44 lines
1.1 KiB
// 父类 Shape
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class Shape {
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// 父类的 draw 方法,子类可以重写
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public void draw() {
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System.out.println("绘制通用图形");
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}
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}
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// 子类 Circle 继承 Shape
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class Circle extends Shape {
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// 重写父类的 draw 方法
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@Override
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public void draw() {
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System.out.println("绘制圆形");
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}
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}
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// 子类 Rectangle 继承 Shape
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class Rectangle extends Shape {
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// 重写父类的 draw 方法
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@Override
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public void draw() {
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System.out.println("绘制矩形");
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}
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}
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// 测试类
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public class ShapeTest {
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// 多态核心方法:接收 Shape 类型参数,自动调用对应子类的 draw
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public static void drawShape(Shape s) {
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s.draw();
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}
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public static void main(String[] args) {
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// 测试多态
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Shape circle = new Circle();
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Shape rectangle = new Rectangle();
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Shape shape = new Shape();
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drawShape(shape); // 输出:绘制通用图形
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drawShape(circle); // 输出:绘制圆形
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drawShape(rectangle); // 输出:绘制矩形
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}
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}
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