设计模式之适配器模式

适配器模式定义：将一个类的接口，转换成客户期望的另一个接口。适配器让原本接口不兼容的类可以合作无间。

简单定义：封装对象，并提供不同的接口。

简单例子：

鸭子接口：

package headfirst.adapter.ducks;public interface Duck {public void quack();public void fly();}

具体鸭子：

package headfirst.adapter.ducks;public class MallardDuck implements Duck {public void quack() {System.out.println("Quack");} public void fly() {System.out.println("I'm flying");}}

火鸡接口：

package headfirst.adapter.ducks;public interface Turkey {public void gobble();public void fly();}

具体火鸡：

package headfirst.adapter.ducks;public class WildTurkey implements Turkey {public void gobble() {System.out.println("Gobble gobble");} public void fly() {System.out.println("I'm flying a short distance");}}

将火鸡适配成鸭子：

package headfirst.adapter.ducks;public class TurkeyAdapter implements Duck {Turkey turkey; public TurkeyAdapter(Turkey turkey) {this.turkey = turkey;}    public void quack() {turkey.gobble();}  public void fly() {for(int i=0; i < 5; i++) {turkey.fly();}}}

测试：

package headfirst.adapter.ducks;public class DuckTestDrive {public static void main(String[] args) {MallardDuck duck = new MallardDuck(); WildTurkey turkey = new WildTurkey();Duck turkeyAdapter = new TurkeyAdapter(turkey);   System.out.println("The Turkey says...");turkey.gobble();turkey.fly(); System.out.println("\nThe Duck says...");testDuck(duck);  System.out.println("\nThe TurkeyAdapter says...");testDuck(turkeyAdapter);} static void testDuck(Duck duck) {duck.quack();duck.fly();}}

输出：

The Turkey says...Gobble gobbleI'm flying a short distanceThe Duck says...QuackI'm flyingThe TurkeyAdapter says...Gobble gobbleI'm flying a short distanceI'm flying a short distanceI'm flying a short distanceI'm flying a short distanceI'm flying a short distance