JAVA设计模式学习笔记-适配器模式

适配器模式：将一个类的接口转换成另一种接口.让原本接口不兼容的类可以兼容.
从用户的角度看不到被适配者，是解耦的
用户调用适配器转化出来的目标接口方法
适配器再调用被适配者的相关接口方法
用户收到反馈结果，感觉只是和目标接口交互

package com.java.test.adaptermode.duck;

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

package com.java.test.adaptermode.duck;

public class GreenHeadDuck implements Duck {

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

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

}

package com.java.test.adaptermode.turkey;

public interface Turkey {

	public void gobble();
	public void fly();

}

package com.java.test.adaptermode.turkey;

public class WildTurkey implements Turkey {

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

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

}

把鸭子适配成火鸡

package com.java.test.adaptermode.adapter;

import com.java.test.adaptermode.duck.Duck;
import com.java.test.adaptermode.turkey.Turkey;

public class TurkeyAdapter implements Duck {
	private 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<6;i++)
		{
			turkey.fly();
		}
	}

}

测试类

package com.java.test.adaptermode;

import com.java.test.adaptermode.adapter.TurkeyAdapter;
import com.java.test.adaptermode.adapter.TurkeyAdapter2;
import com.java.test.adaptermode.duck.Duck;
import com.java.test.adaptermode.duck.GreenHeadDuck;
import com.java.test.adaptermode.turkey.WildTurkey;



public class MainTest {
	public static void main(String[] args) {
		GreenHeadDuck duck=new GreenHeadDuck();
		
		WildTurkey turkey=new WildTurkey();
		
		Duck duck2turkeyAdapter=new TurkeyAdapter2();
		turkey.gobble();
		turkey.fly();
		duck.quack();
		duck.fly();
		duck2turkeyAdapter.quack();
		duck2turkeyAdapter.fly();
		
	
	}
}

类适配器
类适配器：通过多重继承目标接口和被适配者类方式来实现适配
多重继承，其中继承的目标接口部分达到适配目的，而继承被适配者类的部分达
到通过调用被适配者类里的方法来实现目标接口的功能

对象适配器与类适配器差异

对象适配器和类适配器使用了不同的方法实现适配，对象适配器使用组合，类适
配器使用继承

新适配器

package com.java.test.adaptermode.adapter;

import com.java.test.adaptermode.duck.Duck;
import com.java.test.adaptermode.turkey.WildTurkey;

public class TurkeyAdapter2 extends WildTurkey implements Duck {

	@Override
	public void quack() {
		// TODO Auto-generated method stub
		super.gobble();
	}
	@Override
	public void fly() {
		// TODO Auto-generated method stub
		super.fly();
		super.fly();
		super.fly();
	}
}

从枚举器到迭代器的适配

package com.java.test.adaptermode.adapter;

import java.util.Enumeration;
import java.util.Iterator;

public class EnumerationIterator implements Iterator<Object> {

	private Enumeration enumeration;
	
	public EnumerationIterator(Enumeration enumeration)
	{
		 this.enumeration= enumeration;
	}
	
	@Override
	public boolean hasNext() {
		// TODO Auto-generated method stub
		return enumeration.hasMoreElements();
	}

	@Override
	public Object next() {
		// TODO Auto-generated method stub
		return enumeration.nextElement();
	}

	@Override
	public void remove() {
		// TODO Auto-generated method stub
		throw new UnsupportedOperationException();
	}

}

装饰者模式与适配器模式的差别