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????????????????????????1995??GoF?Gang of Four?????????:???????????????23?????????????????????????????????

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• ??????Target????????????
• ?????Adapter???????????????
• ?????Adaptee?????????????????

???????USB??????????????USB?????????????

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// ?????????
public class Cable {
    public void surfing() {
        System.out.println("???????>????~");
    }
}
// ??????????
public interface CableToUSB {
    public void handleRequest();
}
// ????????
public class Adapter extends Cable implements CableToUSB {
    @Override
    public void handleRequest() {
        super.surfing(); // ???????
    }
}
// ?????????????
public class Computer {
    public void net(CableToUSB cableToUSB) {
        cableToUSB.handleRequest();
    }
    public static void main(String[] args) {
        Computer computer = new Computer();
        Adapter adapter = new Adapter();
        Cable cable = new Cable(); // ???????????
        computer.net(adapter); // ????
        // ???????>????~
    }
}

?????

// ?????????
public class Cable {
    public void surfing() {
        System.out.println("???????>????~");
    }
}
// ??????????
public interface CableToUSB {
    public void handleRequest();
}
// ????????
public class Adapter implements CableToUSB {
    private Cable cable;
    public Adapter(Cable cable) {
        this.cable = cable;
    }
    @Override
    public void handleRequest() {
        cable.surfing(); // ???????
    }
}
// ?????????????
public class Computer {
    public void net(CableToUSB cableToUSB) {
        cableToUSB.handleRequest();
    }
    public static void main(String[] args) {
        Computer computer = new Computer();
        Cable cable = new Cable(); // ??????
        Adapter adapter = new Adapter(cable); // ??????????
        computer.net(adapter); // ????
        // ???????>????~
    }
}

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Java??IO?

Java??InputStreamReader?OutputStreamWriter?????????????

• InputStreamReader???????????
• OutputStreamWriter???????????

SpringMVC??DispatcherServlet

SpringMVC??HandlerAdapter?????????????????

public interface HandlerAdapter {
    void handle(Request request, Response response, String handler);
}

Java????Enumeration

Collections.enumeration()???????????????????

public static 
   
     Enumeration
    
      enumeration(Collection
     
       c) {
    return new Enumeration
      
       () {
        Iterator
       
         i = c.iterator();
        public boolean hasMoreElements() { return i.hasNext(); }
        public T nextElement() { return i.next(); }
    };
}
       
      
     
    
   

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