77 lines
1.5 KiB
Dart
77 lines
1.5 KiB
Dart
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/**
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外观模式（Facade Pattern）
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意图：为子系统中的一组接口提供一个一致的界面，外观模式定义了一个高层接口，这个接口使得这一子系统更加容易使用。
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主要解决：降低访问复杂系统的内部子系统时的复杂度，简化客户端与之的接口。
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何时使用：
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1、客户端不需要知道系统内部的复杂联系，整个系统只需提供一个"接待员"即可。
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2、定义系统的入口。
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如何解决：客户端不与系统耦合，外观类与系统耦合。
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*/
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main(List<String> args) {
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ShapeMaker shapeMaker = new ShapeMaker();
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shapeMaker.drawCircle();
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shapeMaker.drawRectangle();
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shapeMaker.drawSquare();
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}
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//////////////////////////////////////////////////////////////////
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///
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/// 创建一个接口
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///
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abstract class Shape {
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void draw();
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}
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///
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/// 创建实现接口的实体类
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///
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class Rectangle implements Shape {
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@override
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void draw() {
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print("Rectangle::draw()");
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}
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}
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class Square implements Shape {
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@override
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void draw() {
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print("Square::draw()");
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}
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}
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class Circle implements Shape {
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@override
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void draw() {
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print("Circle::draw()");
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}
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}
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///
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/// 创建一个外观类
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///
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class ShapeMaker {
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Shape circle;
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Shape rectangle;
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Shape square;
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ShapeMaker() {
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circle = Circle();
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rectangle = Rectangle();
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square = Square();
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}
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void drawCircle() {
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circle.draw();
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}
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void drawRectangle() {
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rectangle.draw();
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}
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void drawSquare() {
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square.draw();
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}
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}
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