Head First设计模式（7）：适配器模式

更多的可以参考我的博客，也在陆续更新ing
http://www.hspweb.cn/

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

这个适配器充满着良好地OO设计原则：使用对象组合，以修改的接口包装被适配者：这种做法还有额外的缺点,那就是，被适配者的任何子类，都可以搭配着适配器使用。
下面以火鸡包装成一个鸭子为例子：

1.目录

image

2.package duck

①. Duck.java

package duck;
public interface Duck {
    public void quack();
    public void fly();
}

②.MallardDuck.java

package duck;

public class MallardDuck implements Duck{

    @Override
    public void quack() {
        // TODO Auto-generated method stub
        System.out.println("quack");
    }

    @Override
    public void fly() {
        // TODO Auto-generated method stub
        System.out.println("I am flying");
    }

}

2.package turkey

①.Turkey.java

package turkey;

public interface Turkey {
    public void gobble();
    public void fly();
}

②.WildTurkey.java

package turkey;

public class WildTurkey implements Turkey{

    @Override
    public void gobble() {
        // TODO Auto-generated method stub
        System.out.println("Gobble gobble");
    }

    @Override
    public void fly() {
        // TODO Auto-generated method stub
        System.out.println("I am flying a short distance");
    }

}

3.package adapter

①.TurkeyAdapter.java

package adapter;
import duck.Duck;
import turkey.Turkey;
public class TurkeyAdapter implements Duck{
    Turkey turkey;
    public TurkeyAdapter (Turkey turkey){
        this.turkey=turkey;
    }
    @Override
    public void quack() {
        // TODO Auto-generated method stub
        turkey.gobble();
    }

    @Override
    public void fly() {
        // TODO Auto-generated method stub
        for(int i=0;i<5;i++){
            turkey.fly();
        }
    }

}

4.package test

①.test.java

package test;

import adapter.TurkeyAdapter;
import duck.Duck;
import duck.MallardDuck;
import turkey.WildTurkey;

public class Test {
    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(turkeyAdapter);
    }

    private static void testDuck(Duck duck) {
        // TODO Auto-generated method stub
        duck.quack();
        duck.fly();
    }
}

补充类图

image