java設計模式-適配器模式

最近在看springmvc, 其中使用了適配器模式, 然後我根據框架中思想, 寫了一下我理解的適配器模式 .

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適配器接口 :

public interface HandlerAdapter {

    public void handle(Object handler);

    public boolean support(Object handler);
}

具體適配器OneHandlerAdapter :

public class OneHandlerAdapter implements HandlerAdapter {

    // 如果適配器合適, 調用相應方法
    @Override
    public void handle(Object handler) {
        if(handler instanceof OneHandler) {
            ((OneHandler)handler).oneHandle();
        }
    }

    // 詢問適配器是否符合, CustomHandlerAdapter只適合CustomHandler
    @Override
    public boolean support(Object handler) {
        return handler instanceof OneHandler;
    }

}

具體適配器TwoHandlerAdapter :

public class TwoHandlerAdapter implements HandlerAdapter {

    // 如果適配器合適, 調用相應方法
    @Override
    public void handle(Object handler) {
        if(handler instanceof TwoHandler) {
            ((TwoHandler)handler).twoHandle();
        }
    }

    // 詢問適配器是否符合, CustomHandlerAdapter只適合CustomHandler
    @Override
    public boolean support(Object handler) {
        return handler instanceof TwoHandler;
    }

}

需要被適配的OneHandler :

public class OneHandler {

    public void oneHandle() {
        System.out.println("i love you one ");
    }
}

需要被適配的TwoHandler :

public class TwoHandler {

    public void twoHandle() {
        System.out.println("i love you two");
    }
}

客戶端使用 :

public class MainController {

    private List<HandlerAdapter> listAdapters = new ArrayList<>();
    {
        listAdapters.add(new OneHandlerAdapter());
        listAdapters.add(new TwoHandlerAdapter());
    }

    public void doDispatcher() {
        // 1.先獲取一個需要被適配的類(這個類可變,可以是從配置文件獲取等)
        TwoHandler handler = new TwoHandler();
        //OneHandler handler = new OneHandler();
        // 2.然後一個一個匹配尋找合適的適配器(目標接口, 客戶需要的接口)
        HandlerAdapter adapter = getHandlerAdapter(handler);
        // 3.進行使用
        adapter.handle(handler);
    }

    public HandlerAdapter getHandlerAdapter(Object handler) {
        for(HandlerAdapter adapter : listAdapters) {
            if(adapter.support(handler)){
                return adapter;
            }
        }
        return null;
    }

    public static void main(String[] args) {
        MainController controller = new MainController();
        controller.doDispatcher();
    }
}