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适配器模式-结构化
类适配器
上代码
/*******************************************************************************
* Package: com.example.demo.design.adapter.classadapter
* Type: Voltage
* Date: 2022-03-12 10:14
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.classadapter;
/**
* 功能描述：5V电压转换器
*
* @author Songxianyang
* @date 2022-03-12 10:14
*/
public class Change extends Source implements VoltageAdapter {
@Override
public String output5v() {
String v220 = super.output();
v220="5v";
return v220;
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter.classadapter
* Type: Phone
* Date: 2022-03-12 10:28
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.classadapter;
/**
* 功能描述：手机充电
*
* @author Songxianyang
* @date 2022-03-12 10:28
*/
public class Phone {
private VoltageAdapter adapter;
public Phone(VoltageAdapter adapter) {
this.adapter = adapter;
}
public void chargePhone() {
System.out.println("我得手机以及充上"+adapter.output5v());
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter
* Type: Source
* Date: 2022-03-12 10:03
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.classadapter;
/**
* 类适配器
* 功能描述：电源类220v 被适配器
*
* @author Songxianyang
* @date 2022-03-12 10:03
*/
public class Source {
public String output() {
return "220v";
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter.classadapter
* Type: Test
* Date: 2022-03-12 10:34
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.classadapter;
/**
* 功能描述：
*
* @author Songxianyang
* @date 2022-03-12 10:34
*/
public class Test {
public static void main(String[] args) {
Phone phone = new Phone(new Change());
phone.chargePhone();
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter.classadapter
* Type: SourceAdapter
* Date: 2022-03-12 10:06
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.classadapter;
/**
* 功能描述： 充电器适配器
*
* @author Songxianyang
* @date 2022-03-12 10:06
*/
public interface VoltageAdapter {
/**
* 输出5v电压
* @return s
*/
String output5v();
}
对象适配器
/*******************************************************************************
* Package: com.example.demo.design.adapter.classadapter
* Type: Voltage
* Date: 2022-03-12 10:14
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.objadapter;
/**
* 功能描述：5V电压转换器 ：适配器
*
* @author Songxianyang
* @date 2022-03-12 10:14
*/
public class Change {
private Source source = new Source();
public String output5v() {
String v220 = source.output();
v220="5v";
return v220;
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter.classadapter
* Type: Phone
* Date: 2022-03-12 10:28
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.objadapter;
/**
* 功能描述：手机充电
*
* @author Songxianyang
* @date 2022-03-12 10:28
*/
public class Phone {
private Change change= new Change();
public void chargePhone() {
System.out.println("我得手机以及充上"+change.output5v());
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter
* Type: Source
* Date: 2022-03-12 10:03
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.objadapter;
/**
* 类适配器
* 功能描述：电源类220v 被适配器
*
* @author Songxianyang
* @date 2022-03-12 10:03
*/
public class Source {
public String output() {
return "220v";
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter.classadapter
* Type: Test
* Date: 2022-03-12 10:34
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.objadapter;
/**
* 功能描述：
*
* @author Songxianyang
* @date 2022-03-12 10:34
*/
public class Test {
public static void main(String[] args) {
Phone phone = new Phone();
phone.chargePhone();
}
}
接口适配器
结构：
代码以及优化
/*******************************************************************************
* Package: com.example.demo.design.adapter.interfaceadapter
* Type: AVoltageAdapter
* Date: 2022-03-12 15:48
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.interfaceadapter;
/**
* 功能描述：抽象的一个多种电压 初始化
*
* @author Songxianyang
* @date 2022-03-12 15:48
*/
public abstract class AbsVoltageAdapter implements IVoltageAdapter {
@Override
public String v5() {
return null;
}
@Override
public String v21() {
return null;
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter.interfaceadapter
* Type: V
* Date: 2022-03-12 15:47
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.interfaceadapter;
/**
* 功能描述： 多种电压 接口
*
* @author Songxianyang
* @date 2022-03-12 15:47
*/
public interface IVoltageAdapter {
/**
* 充手机
* @return s
*/
public String v5();
/**
* 充电车
* @return s
*/
String v21();
/*
......
*/
}
/*******************************************************************************
* Package: com.example.demo.design.adapter.interfaceadapter
* Type: Phone
* Date: 2022-03-12 15:56
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.interfaceadapter;
/**
* 功能描述：手机需要5v电压
*
* @author Songxianyang
* @date 2022-03-12 15:56
*/
public class Phone {
private AbsVoltageAdapter abs;
public Phone(AbsVoltageAdapter abs) {
this.abs = abs;
}
public void change() {
System.out.println("小米手机已经充上"+abs.v5());
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter.interfaceadapter
* Type: PhoneAdapter
* Date: 2022-03-12 15:53
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.interfaceadapter;
/**
* 功能描述：手机适配器5v
* 优化点
* @author Songxianyang
* @date 2022-03-12 15:53
*/
public class PhoneAdapter extends AbsVoltageAdapter {
@Override
public String v5() {
return "5v";
}
}
/*******************************************************************************
* Package: com.example.demo.design.adapter.classadapter
* Type: Test
* Date: 2022-03-12 10:34
*
* Copyright (c) 2022 HUANENG GUICHENG TRUST CORP.,LTD All Rights Reserved.
*
* You may not use this file except in compliance with the License.
*******************************************************************************/
package com.example.demo.design.adapter.interfaceadapter;
/**
* 功能描述：
*
* @author Songxianyang
* @date 2022-03-12 10:34
*/
public class Test {
public static void main(String[] args) {
Phone phone = new Phone(new PhoneAdapter());
phone.change();
}
}
源码分析 mvc
源码 分析
DispatcherServlet dispatcherServlet = new DispatcherServlet();
DispatcherServlet：{
方法：
doDispatch(HttpServletRequest request){
// 获取 request
HttpServletRequest processedRequest = request;
// 执行器对象：Handler
HandlerExecutionChain mappedHandler = null;
// 获取映射执行器对象
mappedHandler = this.getHandler(processedRequest);
// 获取具体的 HandlerAdapter 的适配器
HandlerAdapter ha = this.getHandlerAdapter(mappedHandler.getHandler());
// 不同的适配器 返回不同的 mv
mv = ha.handle(processedRequest, response, mappedHandler.getHandler());
//被调用的代码
//遍历获取具体的handler 并返回
protected HandlerAdapter getHandlerAdapter(Object handler) throws ServletException {
if (this.handlerAdapters != null) {
Iterator var2 = this.handlerAdapters.iterator();
while(var2.hasNext()) {
HandlerAdapter adapter = (HandlerAdapter)var2.next();
if (adapter.supports(handler)) {
return adapter;
}
}
}
throw new ServletException("No adapter for handler [" + handler + "]: The DispatcherServlet configuration needs to include a HandlerAdapter that supports this handler");
}
}
//接口 ：具体的实现 有6个适配器
public interface HandlerAdapter {
handler 标记
boolean supports(Object handler);
@Nullable
ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception;
@Deprecated
long getLastModified(HttpServletRequest request, Object handler);
}
}
适配器到此结束；
