设计模式之适配器

1.类适配

2.对象适配

3.接口适配

1.类适配

待适配的接口

package com.yun.base.design.adapter;

public interface Targetable {  
      
    /* 与原类中的方法相同 */  
    public void method1();  
  
    /* 新类的方法 */  
    public void method2();  
}  

待适配的类

package com.yun.base.design.adapter;

/**
 * 01、类的适配器模式
 * 核心思想就是：有一个Source类，拥有一个方法，待适配，
 * 目标接口是Targetable，通过Adapter类，将Source的功能扩展到Targetable里
 * @author Administrator
 *
 */
public class Source {

    public void method1() {  
        System.out.println("this is original method!");  
    }
      
}

适配器

package com.yun.base.design.adapter;

/**
 * 01、类的适配器模式
 * 核心思想就是：有一个Source类，拥有一个方法，待适配，
 * 目标接口是Targetable，通过Adapter类，将Source的功能扩展到Targetable里
 * @author Administrator
 *
 */
public class Adapter extends Source implements Targetable {  
      
    @Override  
    public void method2() {  
        System.out.println("this is the targetable method!");  
    }  
}

2.对象适配

待适配接口 Targetable ，待适配类 Source

适配器

package com.yun.base.design.adapter;

/**
 * 02、对象的适配器模式 基本思路和类的适配器模式相同，只是将Adapter类作修改，这次不继承Source类，
 * 而是持有Source类的实例，以达到解决兼容性的问题
 * @author Administrator
 *
 */
public class Wrapper implements Targetable {  
      
    private Source source;  
      
    public Wrapper(Source source){  
        super();  
        this.source = source;  
    }  
    @Override  
    public void method2() {  
        System.out.println("this is the targetable method!");  
    }  
  
    @Override  
    public void method1() {  
        source.method1();  
    }  
}

3.接口适配

待适配接口 Sourceable，待适配的类

抽象类

package com.yun.base.design.adapter;

public abstract class Wrapper2 implements Sourceable{  
    
    public void method1(){}  
    public void method2(){}  
} 

实现

package com.yun.base.design.adapter;

public class SourceSub1 extends Wrapper2 {  
    public void method1(){  
        System.out.println("the sourceable interface's first Sub1!");  
    }  
}

package com.yun.base.design.adapter;

public class SourceSub2 extends Wrapper2 {  
    public void method2(){  
        System.out.println("the sourceable interface's second Sub2!");  
    }  
}

4.测试

package com.yun.base.design.adapter;

public class AdapterTest {

    public static void main(String[] args) {  
        //类适配
        classAdapter();
        //对象适配
        objectAdapter();
        //接口适配
        interfaceAdapter();
    }  
    
    /**
     * 类适配
     */
    public static void classAdapter() {
        Targetable target = new Adapter();  
        target.method1();  
        target.method2();  
    }
    
    /**
     * 对象适配
     */
    public static void objectAdapter() {
        Source source = new Source();  
        Targetable target = new Wrapper(source);  
        target.method1();  
        target.method2();  
    }
    
    /**
     * 接口适配
     */
    public static void interfaceAdapter() {
        Sourceable source1 = new SourceSub1();  
        Sourceable source2 = new SourceSub2();  
        
        source1.method1();  
        source1.method2();  
        source2.method1();  
        source2.method2();  
    }
    
}