适配器模式

 
public class Adapter implements Dog, Cat
{
    private Dog dog;
    private Cat cat;
 
    public Dog getDog()
    {
        return dog;
    }
 
    public void setDog(Dog dog)
    {
        this.dog = dog;
    }
 
    public Cat getCat()
    {
        return cat;
    }
 
    public void setCat(Cat cat)
    {
        this.cat = cat;
    }
 
    @Override
    public void miao()
    {
        System.out.print("猫学");
        dog.wang();
    }
 
    @Override
    public void catchMouse()
    {
        cat.catchMouse();
    }
 
    @Override
    public void wang()
    {
        dog.wang();
    }
 
    @Override
    public void act()
    {
        System.out.print("狗学");
        cat.catchMouse();
    }
}
 
public interface Cat
{
    //猫叫
    public void miao();
    //猫捉老鼠
    public void catchMouse();
}
 
public class CatImpl implements Cat
{
    @Override
    public void miao()
    {
        System.out.println("猫叫:喵喵喵");
    }
 
    @Override
    public void catchMouse()
    {
        System.out.println("猫捉老鼠");
    }
}
 
public interface Dog
{
    //狗叫
    public void wang();
    //狗捉鸡
    public void act();
}
 
 
public class DogImpl implements Dog
{
    @Override
    public void act()
    {
        System.out.println("狗捉鸡");
    }
 
    @Override
    public void wang()
    {
        System.out.println("狗叫：汪汪汪");
    }
}
 
public class Client
{
    public static void main(String[] args)
    {
        //实例化猫和狗
        Cat cat = new CatImpl();
        Dog dog = new DogImpl();
        //猫叫
        cat.miao();
        //狗捉鸡
        dog.act();
        //实例化双向适配器
        Adapter adapter = new Adapter();
        //将狗对象设置到适配器中
        adapter.setDog(dog);
        //将猫对象设置到适配器中
        adapter.setCat(cat);
        //将适配器对象赋值给猫，实现猫对象学习狗的行为
        cat = adapter;
        //猫学狗叫
        cat.miao();
        //将适配器对象赋值给狗，实现狗对象学习猫的行为
        dog = adapter;
        // 狗学猫捉老鼠
        dog.act();
    }
}