content/references/java-chassis/zh_CN/question-and-answer/faq.html - servicecomb-website - Git at Google


 <!doctype html>
 <html lang="en" class="no-js">
   <head>

       <meta charset="utf-8">
       <meta name="viewport" content="width=device-width,initial-scale=1">


         <link rel="prev" href="../config-reference/rest-transport-client.html">


         <link rel="next" href="question_answer.html">


       <link rel="icon" href="../assets/images/favicon.png">
       <meta name="generator" content="mkdocs-1.6.0, mkdocs-material-9.5.25">


         <title>FAQ - Java Chassis 3 开发指南</title>


       <link rel="stylesheet" href="../assets/stylesheets/main.6543a935.min.css">


         <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
         <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,700,700i%7CRoboto+Mono:400,400i,700,700i&display=fallback">
         <style>:root{--md-text-font:"Roboto";--md-code-font:"Roboto Mono"}</style>


     <script>__md_scope=new URL("..",location),__md_hash=e=>[...e].reduce((e,_)=>(e<<5)-e+_.charCodeAt(0),0),__md_get=(e,_=localStorage,t=__md_scope)=>JSON.parse(_.getItem(t.pathname+"."+e)),__md_set=(e,_,t=localStorage,a=__md_scope)=>{try{t.setItem(a.pathname+"."+e,JSON.stringify(_))}catch(e){}}</script>


   </head>


     <body dir="ltr">


     <input class="md-toggle" data-md-toggle="drawer" type="checkbox" id="__drawer" autocomplete="off">
     <input class="md-toggle" data-md-toggle="search" type="checkbox" id="__search" autocomplete="off">
     <label class="md-overlay" for="__drawer"></label>
     <div data-md-component="skip">


         <a href="#_1" class="md-skip">
           Skip to content
         </a>

     </div>
     <div data-md-component="announce">

     </div>


 <header class="md-header md-header--shadow" data-md-component="header">
   <nav class="md-header__inner md-grid" aria-label="Header">
     <a href="../index.html" title="Java Chassis 3 开发指南" class="md-header__button md-logo" aria-label="Java Chassis 3 开发指南" data-md-component="logo">


   <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12 8a3 3 0 0 0 3-3 3 3 0 0 0-3-3 3 3 0 0 0-3 3 3 3 0 0 0 3 3m0 3.54C9.64 9.35 6.5 8 3 8v11c3.5 0 6.64 1.35 9 3.54 2.36-2.19 5.5-3.54 9-3.54V8c-3.5 0-6.64 1.35-9 3.54Z"/></svg>

     </a>
     <label class="md-header__button md-icon" for="__drawer">

       <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M3 6h18v2H3V6m0 5h18v2H3v-2m0 5h18v2H3v-2Z"/></svg>
     </label>
     <div class="md-header__title" data-md-component="header-title">
       <div class="md-header__ellipsis">
         <div class="md-header__topic">
           <span class="md-ellipsis">
             Java Chassis 3 开发指南
           </span>
         </div>
         <div class="md-header__topic" data-md-component="header-topic">
           <span class="md-ellipsis">

               FAQ

           </span>
         </div>
       </div>
     </div>


       <script>var media,input,key,value,palette=__md_get("__palette");if(palette&&palette.color){"(prefers-color-scheme)"===palette.color.media&&(media=matchMedia("(prefers-color-scheme: light)"),input=document.querySelector(media.matches?"[data-md-color-media='(prefers-color-scheme: light)']":"[data-md-color-media='(prefers-color-scheme: dark)']"),palette.color.media=input.getAttribute("data-md-color-media"),palette.color.scheme=input.getAttribute("data-md-color-scheme"),palette.color.primary=input.getAttribute("data-md-color-primary"),palette.color.accent=input.getAttribute("data-md-color-accent"));for([key,value]of Object.entries(palette.color))document.body.setAttribute("data-md-color-"+key,value)}</script>


       <label class="md-header__button md-icon" for="__search">

         <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M9.5 3A6.5 6.5 0 0 1 16 9.5c0 1.61-.59 3.09-1.56 4.23l.27.27h.79l5 5-1.5 1.5-5-5v-.79l-.27-.27A6.516 6.516 0 0 1 9.5 16 6.5 6.5 0 0 1 3 9.5 6.5 6.5 0 0 1 9.5 3m0 2C7 5 5 7 5 9.5S7 14 9.5 14 14 12 14 9.5 12 5 9.5 5Z"/></svg>
       </label>
       <div class="md-search" data-md-component="search" role="dialog">
   <label class="md-search__overlay" for="__search"></label>
   <div class="md-search__inner" role="search">
     <form class="md-search__form" name="search">
       <input type="text" class="md-search__input" name="query" aria-label="Search" placeholder="Search" autocapitalize="off" autocorrect="off" autocomplete="off" spellcheck="false" data-md-component="search-query" required>
       <label class="md-search__icon md-icon" for="__search">

         <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M9.5 3A6.5 6.5 0 0 1 16 9.5c0 1.61-.59 3.09-1.56 4.23l.27.27h.79l5 5-1.5 1.5-5-5v-.79l-.27-.27A6.516 6.516 0 0 1 9.5 16 6.5 6.5 0 0 1 3 9.5 6.5 6.5 0 0 1 9.5 3m0 2C7 5 5 7 5 9.5S7 14 9.5 14 14 12 14 9.5 12 5 9.5 5Z"/></svg>

         <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M20 11v2H8l5.5 5.5-1.42 1.42L4.16 12l7.92-7.92L13.5 5.5 8 11h12Z"/></svg>
       </label>
       <nav class="md-search__options" aria-label="Search">

         <button type="reset" class="md-search__icon md-icon" title="Clear" aria-label="Clear" tabindex="-1">

           <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M19 6.41 17.59 5 12 10.59 6.41 5 5 6.41 10.59 12 5 17.59 6.41 19 12 13.41 17.59 19 19 17.59 13.41 12 19 6.41Z"/></svg>
         </button>
       </nav>

     </form>
     <div class="md-search__output">
       <div class="md-search__scrollwrap" data-md-scrollfix>
         <div class="md-search-result" data-md-component="search-result">
           <div class="md-search-result__meta">
             Initializing search
           </div>
           <ol class="md-search-result__list" role="presentation"></ol>
         </div>
       </div>
     </div>
   </div>
 </div>


   </nav>

 </header>

     <div class="md-container" data-md-component="container">


       <main class="md-main" data-md-component="main">
         <div class="md-main__inner md-grid">


               <div class="md-sidebar md-sidebar--primary" data-md-component="sidebar" data-md-type="navigation" >
                 <div class="md-sidebar__scrollwrap">
                   <div class="md-sidebar__inner">


 <nav class="md-nav md-nav--primary" aria-label="Navigation" data-md-level="0">
   <label class="md-nav__title" for="__drawer">
     <a href="../index.html" title="Java Chassis 3 开发指南" class="md-nav__button md-logo" aria-label="Java Chassis 3 开发指南" data-md-component="logo">


   <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12 8a3 3 0 0 0 3-3 3 3 0 0 0-3-3 3 3 0 0 0-3 3 3 3 0 0 0 3 3m0 3.54C9.64 9.35 6.5 8 3 8v11c3.5 0 6.64 1.35 9 3.54 2.36-2.19 5.5-3.54 9-3.54V8c-3.5 0-6.64 1.35-9 3.54Z"/></svg>

     </a>
     Java Chassis 3 开发指南
   </label>

   <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../index.html" class="md-nav__link">


   <span class="md-ellipsis">
     概述
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../start/design.html" class="md-nav__link">


   <span class="md-ellipsis">
     Java Chassis设计参考
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../introduce3.x.x.html" class="md-nav__link">


   <span class="md-ellipsis">
     Java Chassis 3版本介绍
   </span>


       </a>
     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_4" >


           <label class="md-nav__link" for="__nav_4" id="__nav_4_label" tabindex="0">


   <span class="md-ellipsis">
     快速入门
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_4_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_4">
             <span class="md-nav__icon md-icon"></span>
             快速入门
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../start/development-environment.html" class="md-nav__link">


   <span class="md-ellipsis">
     安装本地开发环境
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../start/first-sample.html" class="md-nav__link">


   <span class="md-ellipsis">
     开发第一个微服务应用
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../featured-topics/application-bmi.html" class="md-nav__link">


   <span class="md-ellipsis">
     BMI应用-使用服务治理
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../featured-topics/application-porter.html" class="md-nav__link">


   <span class="md-ellipsis">
     PORTER应用-典型开发场景
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item">
       <a href="../build-provider/definition/service-definition.html" class="md-nav__link">


   <span class="md-ellipsis">
     微服务定义
   </span>


       </a>
     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_6" >


           <label class="md-nav__link" for="__nav_6" id="__nav_6_label" tabindex="0">


   <span class="md-ellipsis">
     Spring Boot集成Java Chassis
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_6_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_6">
             <span class="md-nav__icon md-icon"></span>
             Spring Boot集成Java Chassis
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../spring-boot/introduction.html" class="md-nav__link">


   <span class="md-ellipsis">
     Spring Boot集成Java Chassis介绍
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../spring-boot/diff-spring-mvc.html" class="md-nav__link">


   <span class="md-ellipsis">
     与Spring Web MVC开发习惯的差异
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_7" >


           <label class="md-nav__link" for="__nav_7" id="__nav_7_label" tabindex="0">


   <span class="md-ellipsis">
     开发服务提供者
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_7_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_7">
             <span class="md-nav__icon md-icon"></span>
             开发服务提供者
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../build-provider/basics.html" class="md-nav__link">


   <span class="md-ellipsis">
     基础概念
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/http-mapping.html" class="md-nav__link">


   <span class="md-ellipsis">
     HTTP参数映射参考
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/jaxrs.html" class="md-nav__link">


   <span class="md-ellipsis">
     用JAX-RS开发微服务
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/springmvc.html" class="md-nav__link">


   <span class="md-ellipsis">
     用SpringMVC开发微服务
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/transparent-rpc.html" class="md-nav__link">


   <span class="md-ellipsis">
     用透明RPC开发微服务
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/use-interface.html" class="md-nav__link">


   <span class="md-ellipsis">
     只发布interface的方法为服务接口
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/reactive.html" class="md-nav__link">


   <span class="md-ellipsis">
     异步处理
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/context-param.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用 Context 参数
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/multi-code.html" class="md-nav__link">


   <span class="md-ellipsis">
     多个返回值和错误码
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/swagger-annotation.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用Swagger注解
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/interface-constraints.html" class="md-nav__link">


   <span class="md-ellipsis">
     接口定义和数据类型
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/listen-address-and-publish-address.html" class="md-nav__link">


   <span class="md-ellipsis">
     服务监听地址和发布地址
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/thread-pool.html" class="md-nav__link">


   <span class="md-ellipsis">
     线程池
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/event-listener.html" class="md-nav__link">


   <span class="md-ellipsis">
     服务启动事件
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/parameter-validator.html" class="md-nav__link">


   <span class="md-ellipsis">
     参数效验
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/bootup.html" class="md-nav__link">


   <span class="md-ellipsis">
     程序启动逻辑
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/ipv6-configuration.html" class="md-nav__link">


   <span class="md-ellipsis">
     IPV6配置和使用
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_8" >


           <label class="md-nav__link" for="__nav_8" id="__nav_8_label" tabindex="0">


   <span class="md-ellipsis">
     开发服务消费者
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_8_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_8">
             <span class="md-nav__icon md-icon"></span>
             开发服务消费者
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../build-consumer/basics.html" class="md-nav__link">


   <span class="md-ellipsis">
     基础概念
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-consumer/using-resttemplate.html" class="md-nav__link">


   <span class="md-ellipsis">
     Restful风格 - 使用 RestOperations
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-consumer/develop-consumer-using-rpc.html" class="md-nav__link">


   <span class="md-ellipsis">
     RPC风格
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-consumer/invoker.html" class="md-nav__link">


   <span class="md-ellipsis">
     泛化调用
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_9" >


           <label class="md-nav__link" for="__nav_9" id="__nav_9_label" tabindex="0">


   <span class="md-ellipsis">
     定制请求处理流程
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_9_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_9">
             <span class="md-nav__icon md-icon"></span>
             定制请求处理流程
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../references-handlers/intruduction.html" class="md-nav__link">


   <span class="md-ellipsis">
     处理链介绍
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_10" >


           <label class="md-nav__link" for="__nav_10" id="__nav_10_label" tabindex="0">


   <span class="md-ellipsis">
     通用功能开发
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_10_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_10">
             <span class="md-nav__icon md-icon"></span>
             通用功能开发
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../general-development/local-develop-test.html" class="md-nav__link">


   <span class="md-ellipsis">
     本地开发和测试
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/upload-download.html" class="md-nav__link">


   <span class="md-ellipsis">
     文件上传下载
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/reactive.html" class="md-nav__link">


   <span class="md-ellipsis">
     Reactive
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/dnsconfig.html" class="md-nav__link">


   <span class="md-ellipsis">
     DNS自定义配置
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/proxy.html" class="md-nav__link">


   <span class="md-ellipsis">
     代理设置
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/report-framework-version.html" class="md-nav__link">


   <span class="md-ellipsis">
     框架上报版本号
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/cross-app-invocation.html" class="md-nav__link">


   <span class="md-ellipsis">
     跨应用调用
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/secret-field.html" class="md-nav__link">


   <span class="md-ellipsis">
     定制序列化和反序列化方法
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/context.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用Context传递控制消息
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/produceprocess.html" class="md-nav__link">


   <span class="md-ellipsis">
     返回值序列化扩展
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/CORS.html" class="md-nav__link">


   <span class="md-ellipsis">
     跨域资源共享(CORS)
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/AlarmEvent.html" class="md-nav__link">


   <span class="md-ellipsis">
     获取熔断与实例隔离告警事件信息
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/shutdown.html" class="md-nav__link">


   <span class="md-ellipsis">
     优雅停机
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/error-handling.html" class="md-nav__link">


   <span class="md-ellipsis">
     异常处理
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/multienvironment.html" class="md-nav__link">


   <span class="md-ellipsis">
     微服务实例间多环境隔离
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/thread-model.html" class="md-nav__link">


   <span class="md-ellipsis">
     线程模型
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/config-logs.html" class="md-nav__link">


   <span class="md-ellipsis">
     配置日志
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_11" >


           <label class="md-nav__link" for="__nav_11" id="__nav_11_label" tabindex="0">


   <span class="md-ellipsis">
     多样化的通信协议功能
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_11_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_11">
             <span class="md-nav__icon md-icon"></span>
             多样化的通信协议功能
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../transports/introduction.html" class="md-nav__link">


   <span class="md-ellipsis">
     多协议介绍
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../transports/rest-over-vertx.html" class="md-nav__link">


   <span class="md-ellipsis">
     REST over HTTP(Vert.x)
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../transports/http2.html" class="md-nav__link">


   <span class="md-ellipsis">
     REST over HTTP2(Vert.x)
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../transports/rest-over-servlet-embedded.html" class="md-nav__link">


   <span class="md-ellipsis">
     REST over Servlet(Spring Boot Embedded)
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../transports/rest-over-servlet.html" class="md-nav__link">


   <span class="md-ellipsis">
     REST over Servlet(WAR)
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../transports/highway-rpc.html" class="md-nav__link">


   <span class="md-ellipsis">
     Highway
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_12" >


           <label class="md-nav__link" for="__nav_12" id="__nav_12_label" tabindex="0">


   <span class="md-ellipsis">
     多样化的服务注册与发现功能
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_12_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_12">
             <span class="md-nav__icon md-icon"></span>
             多样化的服务注册与发现功能
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../registry/introduction.html" class="md-nav__link">


   <span class="md-ellipsis">
     注册发现介绍
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../registry/service-center.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用Service Center
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../registry/nacos.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用Nacos
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../registry/zookeeper.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用ZooKeeper
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../registry/local-registry.html" class="md-nav__link">


   <span class="md-ellipsis">
     本地注册发现
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../registry/distributed.html" class="md-nav__link">


   <span class="md-ellipsis">
     去中心化注册发现
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_13" >


           <label class="md-nav__link" for="__nav_13" id="__nav_13_label" tabindex="0">


   <span class="md-ellipsis">
     多样化的配置管理功能
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_13_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_13">
             <span class="md-nav__icon md-icon"></span>
             多样化的配置管理功能
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../config/general-config.html" class="md-nav__link">


   <span class="md-ellipsis">
     服务配置介绍
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../config/read-config.html" class="md-nav__link">


   <span class="md-ellipsis">
     在程序中读取配置信息
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../config/kie.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用Kie
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../config/nacos.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用Nacos
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../config/zookeeper.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用Zookeeper
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../config/apollo.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用Apollo
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../config/cse1.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用CSE1.0配置中心
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_14" >


           <label class="md-nav__link" for="__nav_14" id="__nav_14_label" tabindex="0">


   <span class="md-ellipsis">
     服务治理功能参考
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_14_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_14">
             <span class="md-nav__icon md-icon"></span>
             服务治理功能参考
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../references-handlers/rule-governance.html" class="md-nav__link">


   <span class="md-ellipsis">
     流量特征治理
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../references-handlers/governance-best-practise.html" class="md-nav__link">


   <span class="md-ellipsis">
     流量特征治理最佳实践
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../references-handlers/loadbalance.html" class="md-nav__link">


   <span class="md-ellipsis">
     负载均衡
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../references-handlers/ratelimit.html" class="md-nav__link">


   <span class="md-ellipsis">
     限流
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../references-handlers/router.html" class="md-nav__link">


   <span class="md-ellipsis">
     灰度发布
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../references-handlers/fault-injection.html" class="md-nav__link">


   <span class="md-ellipsis">
     故障注入
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../references-handlers/fail-retry.html" class="md-nav__link">


   <span class="md-ellipsis">
     快速失败和重试
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_15" >


           <label class="md-nav__link" for="__nav_15" id="__nav_15_label" tabindex="0">


   <span class="md-ellipsis">
     网关功能参考
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_15_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_15">
             <span class="md-nav__icon md-icon"></span>
             网关功能参考
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../edge/open-service.html" class="md-nav__link">


   <span class="md-ellipsis">
     介绍
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../edge/by-servicecomb-sdk.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用 Edge Service 做网关
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../edge/zuul.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用 `zuul` 和 `spring cloud gateway` 做网关
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../edge/nginx.html" class="md-nav__link">


   <span class="md-ellipsis">
     nginx 网关简单介绍
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_16" >


           <label class="md-nav__link" for="__nav_16" id="__nav_16_label" tabindex="0">


   <span class="md-ellipsis">
     安全特性参考
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_16_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_16">
             <span class="md-nav__icon md-icon"></span>
             安全特性参考
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../security/publickey.html" class="md-nav__link">


   <span class="md-ellipsis">
     微服务间认证
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../security/tls.html" class="md-nav__link">


   <span class="md-ellipsis">
     使用TLS通信
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_17" >


           <label class="md-nav__link" for="__nav_17" id="__nav_17_label" tabindex="0">


   <span class="md-ellipsis">
     可观测功能参考
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_17_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_17">
             <span class="md-nav__icon md-icon"></span>
             可观测功能参考
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../general-development/metrics.html" class="md-nav__link">


   <span class="md-ellipsis">
     应用性能监控
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../general-development/microservice-invocation-chain.html" class="md-nav__link">


   <span class="md-ellipsis">
     微服务调用链
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../build-provider/access-log-configuration.html" class="md-nav__link">


   <span class="md-ellipsis">
     Access Log配置
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_18" >


           <label class="md-nav__link" for="__nav_18" id="__nav_18_label" tabindex="0">


   <span class="md-ellipsis">
     专题文章
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_18_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_18">
             <span class="md-nav__icon md-icon"></span>
             专题文章
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../featured-topics/features.html" class="md-nav__link">


   <span class="md-ellipsis">
     特性介绍
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../featured-topics/secrets.html" class="md-nav__link">


   <span class="md-ellipsis">
     技术解密
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../featured-topics/upgrading.html" class="md-nav__link">


   <span class="md-ellipsis">
     升级指导
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../featured-topics/compatibility.html" class="md-nav__link">


   <span class="md-ellipsis">
     兼容问题和兼容性策略
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="../featured-topics/performance.html" class="md-nav__link">


   <span class="md-ellipsis">
     性能问题分析和调优
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_19" >


           <label class="md-nav__link" for="__nav_19" id="__nav_19_label" tabindex="0">


   <span class="md-ellipsis">
     常用配置项参考
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_19_label" aria-expanded="false">
           <label class="md-nav__title" for="__nav_19">
             <span class="md-nav__icon md-icon"></span>
             常用配置项参考
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item">
       <a href="../config-reference/rest-transport-client.html" class="md-nav__link">


   <span class="md-ellipsis">
     REST Transport Client 配置项
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


     <li class="md-nav__item md-nav__item--active md-nav__item--nested">


         <input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_20" checked>


           <label class="md-nav__link" for="__nav_20" id="__nav_20_label" tabindex="0">


   <span class="md-ellipsis">
     常见问题
   </span>


             <span class="md-nav__icon md-icon"></span>
           </label>

         <nav class="md-nav" data-md-level="1" aria-labelledby="__nav_20_label" aria-expanded="true">
           <label class="md-nav__title" for="__nav_20">
             <span class="md-nav__icon md-icon"></span>
             常见问题
           </label>
           <ul class="md-nav__list" data-md-scrollfix>


     <li class="md-nav__item md-nav__item--active">

       <input class="md-nav__toggle md-toggle" type="checkbox" id="__toc">


       <a href="faq.html" class="md-nav__link md-nav__link--active">


   <span class="md-ellipsis">
     FAQ
   </span>


       </a>

     </li>


     <li class="md-nav__item">
       <a href="question_answer.html" class="md-nav__link">


   <span class="md-ellipsis">
     Q & A
   </span>


       </a>
     </li>


     <li class="md-nav__item">
       <a href="interface-compatibility.html" class="md-nav__link">


   <span class="md-ellipsis">
     微服务接口兼容常见问题
   </span>


       </a>
     </li>


           </ul>
         </nav>

     </li>


   </ul>
 </nav>
                   </div>
                 </div>
               </div>


               <div class="md-sidebar md-sidebar--secondary" data-md-component="sidebar" data-md-type="toc" >
                 <div class="md-sidebar__scrollwrap">
                   <div class="md-sidebar__inner">


 <nav class="md-nav md-nav--secondary" aria-label="Table of contents">


 </nav>
                   </div>
                 </div>
               </div>


             <div class="md-content" data-md-component="content">
               <article class="md-content__inner md-typeset">


 <h1 id="_1">常见问题</h1>
 <ul>
 <li><a href="#Q2">Q: 契约生成会报错 Caused by: java.lang.Error: OperationId must be unique，不支持函数重载？</a>  </li>
 <li><a href="#Q3">Q: Map类型的key必须使用 String 类型？</a>  </li>
 <li><a href="#Q4">Q: 参数返回值不能使用接口？</a></li>
 <li><a href="#Q5">Q: 参数返回值不能使用泛型？</a></li>
 <li><a href="#Q6">Q: 实现类中 public 方法全部被发布为接口，如何排除？</a></li>
 <li><a href="#Q7">Q: 如何自定义某个Java方法对应的REST接口里的HTTP Status Code？</a></li>
 </ul>
 <h2 id="Q2">Q: 契约生成会报错 Caused by: java.lang.Error: OperationId must be unique，不支持函数重载？</h2>

 <ul>
 <li>A: 支持函数重载，但是需要注意每个接口必须有唯一的operation id。可以加上<code>@ApiOperation</code>标签给重载的接口指定唯一
   的 operation id (对应于 nickname 属性）。示例代码如下：</li>
 </ul>
 <pre><code class="language-java">  @Path(&quot;/sayHi&quot;)
   @GET
   @Produces(&quot;text/plain;charset=UTF-8&quot;)
   @ApiOperation(value = &quot;&quot;, nickname = &quot;sayHi&quot;)
   public String sayHello() {
     return &quot;ApiOperationJaxrsSchema#sayHello&quot;;
   }

   @Path(&quot;/sayHello&quot;)
   @GET
   @Produces(&quot;application/json;charset=UTF-8&quot;)
   @ApiOperation(value = &quot;&quot;, nickname = &quot;sayHello&quot;)
   public String sayHello(@ApiParam(&quot;name&quot;) String name) {
     return name;
   }
 </code></pre>
 <h2 id="Q3">Q: Map类型的 key 必须使用 String 类型？</h2>

 <ul>
 <li>A: 是的。java-chassis 遵循 <a href="https://swagger.io/docs/specification/data-models/dictionaries/">Open API 规范</a>, MAP
   类型的 key 必须使用 String 类型。 业务可以结合实际情况，使用符合规范的类型。 如果必须使用其他类型，
   可以考虑接口定义使用 Object 规避，客户端可以对返回值结果自行进行 json 转换。</li>
 </ul>
 <h2 id="Q4">Q: 参数返回值不能使用接口？</h2>

 <ul>
 <li>A: 是的。java-chassis 不允许参数、返回值的类型为 <code>Interface</code> 或者 <code>Abstract Class</code>。因为这些类型
   无法正确的生成 swagger 描述。如果必须使用这些类型，可以考虑接口定义使用 Object 规避，客户端可以对返回值结果
   自行进行 json 转换。</li>
 </ul>
 <h2 id="Q5">Q: 参数返回值不能使用泛型？</h2>

 <ul>
 <li>A: 可以使用泛型。但是必须明确泛型类型。比如：</li>
 </ul>
 <pre><code class="language-java">  @PostMapping(path = &quot;holderUser&quot;)
   public Holder&lt;User&gt; holderUser(@RequestBody Holder&lt;User&gt; input) {
     Assert.isInstanceOf(Holder.class, input);
     Assert.isInstanceOf(User.class, input.value);
     return input;
   }

   @GetMapping(path = &quot;/genericParams&quot;)
   @ApiOperation(value = &quot;genericParams&quot;, nickname = &quot;genericParams&quot;)
   public List&lt;List&lt;String&gt;&gt; genericParams(@RequestParam(&quot;code&quot;) int code, @RequestBody List&lt;List&lt;String&gt;&gt; names) {
     return names;
   }
 </code></pre>
 <p>未指定泛型类型是不允许的。比如：</p>
 <pre><code class="language-java">  @GetMapping(path = &quot;/genericParams&quot;)
   @ApiOperation(value = &quot;genericParams&quot;, nickname = &quot;genericParams&quot;)
   public List genericParams(@RequestParam(&quot;code&quot;) int code, @RequestBody List names) {
     return names;
   }
 </code></pre>
 <p>如果业务必须使用泛型，并且不能确定类型，可以考虑接口定义使用 Object 规避，客户端可以对返回值结果
 自行进行 json 转换。</p>
 <h2 id="Q6">Q: 实现类中 public 方法全部被发布为接口，如何排除？</h2>

 <ul>
 <li>A: java chassis 会将所有 public 方法发布为接口。 如果有些接口不需要发布为接口，可以使用 @ApiOperation
   标签声明不发布为接口。例子如下：</li>
 </ul>
 <pre><code class="language-java">  @ApiOperation(value = &quot;&quot;, hidden = true)
   public void hidden() {

   }
 </code></pre>
 <p>在迁移改造的过程中，比如将 HSF 和 Dubbo 的内部 RPC 接口改造为 java-chassis 的 RPC 接口，可能还有更加复杂
 的情况，比如：</p>
 <pre><code class="language-java">@HSFProvider(MyInterface.class)
 public MyService extends AbstractMyService implements MyInterface
 </code></pre>
 <p>如果直接改造为</p>
 <pre><code class="language-java">@RpcSchema(schemaId = &quot;MyService&quot;)
 public MyService extends AbstractMyService implements MyInterface
 </code></pre>
 <p>那么 <code>AbstractMyService</code> 的公共方法也会发布为 RPC 接口， 而 HSF 和 dubbo 则不会。 这种情况建议增加
 一个类，而将原来的接口声明为服务类来处理， 比如：</p>
 <pre><code class="language-java">@Service(&quot;MyService&quot;)
 public MyService extends AbstractMyService implements MyInterface

 @RpcSchema(schemaId = &quot;MyServiceImpl&quot;)
 public MyServiceImpl implements MyInterface {
     @Autowired
     @Qualifier(&quot;MyService&quot;)
     MyInterface service;

     public String hello(String name) {
        return service.hello(name);
     }
 }
 </code></pre>
 <h2 id="Q7">Q: 如何自定义某个Java方法对应的REST接口里的HTTP Status Code？</h2>

 <ul>
 <li>A:  对于 2xx 的返回值，可以通过 @ApiResponse 实现，例如：</li>
 </ul>
 <pre><code class="language-java">@ApiResponse(code = 201, response = Integer.class, message = &quot;&quot;)
 public int test(int x) {
   return 100;
 }
 </code></pre>
 <p>对于其他返回值，可以通过抛出自定义的 InvocationException 实现，例如：</p>
 <pre><code class="language-java">@Path(&quot;/errorCode&quot;)
 @POST
 @ApiResponses({
   @ApiResponse(code = 200, response = MultiResponse200.class, message = &quot;&quot;),
   @ApiResponse(code = 400, response = MultiResponse400.class, message = &quot;&quot;),
   @ApiResponse(code = 500, response = MultiResponse500.class, message = &quot;&quot;)})
 public MultiResponse200 errorCode(MultiRequest request) {
     if (request.getCode() == 400) {
       MultiResponse400 r = new MultiResponse400();
       r.setCode(400);
       r.setMessage(&quot;bad request&quot;);
       throw new InvocationException(javax.ws.rs.core.Response.Status.BAD_REQUEST, r);
     } else if (request.getCode() == 500) {
       MultiResponse500 r = new MultiResponse500();
       r.setCode(500);
       r.setMessage(&quot;internal error&quot;);
       throw new InvocationException(javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR, r);
     } else {
       MultiResponse200 r = new MultiResponse200();
       r.setCode(200);
       r.setMessage(&quot;success result&quot;);
       return r;
     }
 }
 </code></pre>
 <ul>
 <li>
 <p><strong>Q: 如何定制自己微服务的日志配置?</strong></p>
 <ul>
 <li>A: ServiceComb不绑定日志器，只是使用了slf4j，用户可以自由选择log4j/log4j2/logback等等。ServiceComb提供了一个log4j的扩展，在标准log4j的基础上，支持log4j的properties文件的增量配置。<ul>
 <li>默认以规则："classpath*:config/log4j.properties"加载配置文件</li>
 <li>实际会搜索出classpath中所有的<code>config/log4j.properties和config/log4j.*.properties</code>, 从搜索出的文件中切出<code>\*</code>的部分，进行alpha排序，然后按顺序加载，最后合成的文件作为log4j的配置文件。</li>
 <li>如果要使用ServiceComb的log4j扩展，则需要调用Log4jUtils.init，否则完全按标准的日志器的规则使用。</li>
 </ul>
 </li>
 </ul>
 </li>
 <li>
 <p><strong>Q: 当服务配置了多个transport的时候，在运行时是怎么选择使用哪个transport的？</strong></p>
 <ul>
 <li>
 <p>A: ServiceComb的consumer、transport、handler、producer之间是解耦的，各功能之间通过契约定义联合在一起工作的，即：
       consumer使用透明rpc，还是springmvc开发与使用highway，还是RESTful在网络上传输没有关系与producer是使用透明rpc，还是jaxrs，
       或者是springmvc开发，也没有关系handler也不感知，业务开发方式以及传输方式。consumer访问producer，在运行时的transport选择上，
       总规则为：cnsumer的transport与producer的endpoint取交集，如果交集后，还有多个transport可选择，则轮流使用，分解开来，存在以下场景：</p>
 <ul>
 <li>
 <p>当一个微服务producer同时开放了highway以及RESTful的endpoint</p>
 <ul>
 <li>consumer进程中只部署了highway transport jar，则只会访问producer的highway endpoint</li>
 <li>consumer进程中只部署了RESTful transport jar，则只会访问producer的RESTful endpoint</li>
 <li>consumer进程中，同时部署了highway和RESTful transport jar，则会轮流访问producer的highway、RESTful endpoint</li>
 </ul>
 </li>
 <li>
 <p>如果consumer想固定使用某个transport访问producer，可以在consumer进程的microservice.yaml中配置，指定transport的名称:</p>
 <pre><code>servicecomb:
     references:
         &lt;service_name&gt;:
             transport: highway
 </code></pre>
 </li>
 <li>
 <p>当一个微服务producer只开放了highway的endpoint</p>
 <ul>
 <li>consumer进程只部署了highway transport jar，则正常使用highway访问</li>
 <li>consumer进程只部署了RESTful transport jar，则无法访问</li>
 <li>consumer进程同时部署了highway和RESTful transport jar，则正常使用highway访问</li>
 </ul>
 </li>
 <li>
 <p>当一个微服务producer只开放了RESTful的endpoint</p>
 <ul>
 <li>consumer进程只部署了highway transport jar，则无法访问</li>
 <li>consumer进程只部署了RESTful transport jar，则正常使用RESTful访问</li>
 <li>consumer进程同时部署了highway和RESTful transport jar，则正常使用RESTful访问</li>
 </ul>
 </li>
 </ul>
 </li>
 </ul>
 </li>
 <li>
 <p><strong>Q: ServiceComb微服务框架服务调用是否使用长连接?</strong></p>
 <ul>
 <li>A: http使用的是长连接（有超时时间），highway方式使用的是长连接（一直保持）。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q: 服务断连服务中心注册信息是否自动删除</strong></p>
 <ul>
 <li>A: 服务中心心跳检测到服务实例不可用，只会移除服务实例信息，服务的静态数据不会移除。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q: 如果使用tomcat方式集成ServiceComb微服务框架，如何实现服务注册</strong></p>
 <ul>
 <li>A: 如果使用ServiceComb sdk servlet方式（使用transport-rest-servlet依赖）制作为war包部署到tomcat，需要保证，
     服务描述文件（microservice.yaml）中rest端口配置和外置容器一致才能实现该服务的正确注册。否则无法感知tomcat开放端口。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q: 如果使用tomcat方式集成ServiceComb微服务框架，服务注册的时候如何将war包部署的上下文注册到服务中心</strong></p>
 <ul>
 <li>A: 发布服务接口的时候需要将war包部署的上下文（context）放在baseurl最前面，这样才能保证注册到服务中心的路径是完整的路径（包含了上下文）。示例：<pre><code>@path(/{context}/xxx)
 class ServiceA
 </code></pre>
 </li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  ServiceComb微服务框架如何实现数据多个微服务间透传</strong></p>
 <ul>
 <li>
 <p>A: 透传数据塞入：</p>
 <pre><code>CseHttpEntity&lt;xxxx.class&gt; httpEntity = new CseHttpEntity&lt;&gt;(xxx);
 //透传内容
 httpEntity.addContext("contextKey","contextValue");
 ResponseEntity&lt;String&gt; responseEntity = RestTemplateBuilder.create()
     .exchange("cse://springmvc/springmvchello/sayhello",HttpMethod.POST,httpEntity,String.class);
 </code></pre>
 <p>透传数据获取：</p>
 <pre><code>@Override
 @RequestMapping(path="/sayhello",method = RequestMethod.POST)
 public String sayHello(@RequestBody Person person,InvocationContext context){
      //透传数据获取
      context.getContext();
      return "Hello person " + person.getName();
 }
 </code></pre>
 </li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  ServiceComb body Model部分暴露</strong></p>
 <ul>
 <li>A: 一个接口对应的body对象中，可能有一些属性是内部的，不想开放出去，生成schema的时候不要带出去，使用：<pre><code>@ApiModelProperty(hidden = true)
 </code></pre>
 </li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  服务超时设置</strong></p>
 <ul>
 <li>A: 在微服务描述文件（microservice.yaml）中添加如下配置：<pre><code>servicecomb:
     request:
         timeout: 30000
 </code></pre>
 </li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  URL 地址就可以唯一定位，为什么要加上一个schema？</strong></p>
 <ul>
 <li>A: <ol>
 <li>schema 是用来匹配服务契约的，用来保证服务端和消费端契约兼容，每个契约需要一个唯一ID，在服务中心存储。</li>
 <li>schema映射到java的interface概念，在consumer使用透明rpc模式开发时，可以找到是微服务里的哪个operation。schema之间的方法名是没有唯一性要求的。</li>
 <li>operation qualified name是治理的key，而URL 因为path参数的存在，没办法直接查找，而qualified name是不会变的。治理是不区分传输的，如果治理按URL 走，那么highway调进来时，还得根据参数反向构造出url，再来正则表达式匹配，太折腾了。</li>
 <li>http只是一种传输通道，还有别的传输通道不需要映射到URL的。</li>
 </ol>
 </li>
 </ul>
 </li>
 <li>
 <p><strong>Q: rest客户端调用的时候，实际上只带上了服务名和URL，并不需要指定schema id的， 而实际上根据这个URL也能找到具体契约的，所以指定schema id作用何在？</strong></p>
 <ul>
 <li>A: 由于透明rpc是接口式调用，并没有URL，内部实际都归一化到operation来描述的，这样就可以结合schema id唯一定位到具体的请求处理中。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  Transport是个什么概念？用来干什么的？</strong></p>
 <ul>
 <li>A: transport负责编解码，以及传输。通信模型有rest和highway两种，highway对应的是私有协议，使用protobuf编码，rest用的是json。highway和rest都是基于vertx做的，vertx是基于netty的。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  ServiceComb和服务中心是怎么交互的?</strong></p>
 <ul>
 <li>A: 走rest，主要负责注册，取数据和心跳等；watch事件走websocket，watch事件是观察服务中心实例信息有没有变更。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  有类似dubbo那种治理中心吗？</strong></p>
 <ul>
 <li>A: bizkeeper是一个handler，是治理的其中一个内容。治理可以通过handler扩展。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q: service path怎么理解？</strong></p>
 <ul>
 <li>A: 每个微服务有一个servicePathManager，每一个schema将自己的path注册进去。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  浏览器能直接访问微服务Endpoint吗？</strong></p>
 <ul>
 <li>A: 可以，restful发布的微服务Endpoint，可以直接在浏览器中使用HTTP加service path访问提供get方法的服务，如果是访问其他Http方法提供的服务建议安装使用<a href="https://www.sap.com/developer/tutorials/api-tools-postman-install.html">Postman</a>。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  契约生成时，需要强制带上版本号和语言吗？</strong></p>
 <ul>
 <li>A: 契约是属于微服务的，微服务本来就有版本，但语言是不应该带上版本号的。应该契约要求与语言无关。契约“没有版本”，契约的版本体现在微服务上，实例能找到所属的微服务的版本，就能找到一个确定的契约。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q: 如果同时引入了<code>transport-rest-servlet</code>和<code>transport-rest-vertx</code>的依赖，那么它怎么决定采用哪一个？</strong></p>
 <ul>
 <li>A: 如果端口没被占用，就用vertx；如果被占用了，就用servlet。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q:  qps流控设计时是出于什么场景考虑的？</strong></p>
 <ul>
 <li>A: 限流有两个主要作用，第一通过给不同的消费者限流保证对一些重点服务的服务效果，第二防止雪崩效应。可根据服务的重要性来决定水管的粗细，ServiceComb是支持消费端限流和服务端限流两种限流方式的，消费端限流可以做到比较精细的控制。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q: 如果服务端是链式调用，即类似a-&gt;b-&gt;c，那设置了qps 流控会不会造成水管粗细不均的事情？</strong></p>
 <ul>
 <li>A: 一般采取的模式是先测量再设置。qps设置最终是结合整体业务需求来进行调控的，而不是就单个节点来进行设置。</li>
 </ul>
 </li>
 <li>
 <p><strong>Q: 如何在契约DTO中忽略中指定的属性？</strong></p>
 <ul>
 <li>
 <p>A: 可以使用@JsonIgnore注解标记需要忽略的属性， 例如:</p>
 <p><code>java
 public class OutputForTest{
     @JsonIgnore
     private String outputId = null;
     private String inputId = null;
     ...
  }</code></p>
 </li>
 </ul>
 </li>
 <li>
 <p><strong>Q: 如何使用数据压缩传输的能力？</strong></p>
 <ul>
 <li>A: 服务端要开启响应数据压缩传输的能力，需要进行如下配置：</li>
 </ul>
 <p><code>yaml
 servicecomb:
   rest:
     server:
       compression: true</code>
 同时，消费端需要同步开启配置项：
 <code>yaml
 servicecomb:
   rest:
     client:
       connection:
         compression: true</code>
 当消费端在请求头中设置Accept-Encoding:gzip, deflate的字段时，服务端就会依据该字段中提供的算法，对响应数据进行压缩处理，并返回。</p>
 </li>
 </ul>


               </article>
             </div>


 <script>var target=document.getElementById(location.hash.slice(1));target&&target.name&&(target.checked=target.name.startsWith("__tabbed_"))</script>
         </div>

       </main>

         <footer class="md-footer">

   <div class="md-footer-meta md-typeset">
     <div class="md-footer-meta__inner md-grid">
       <div class="md-copyright">


     Made with
     <a href="https://squidfunk.github.io/mkdocs-material/" target="_blank" rel="noopener">
       Material for MkDocs
     </a>

 </div>

     </div>
   </div>
 </footer>

     </div>
     <div class="md-dialog" data-md-component="dialog">
       <div class="md-dialog__inner md-typeset"></div>
     </div>


     <script id="__config" type="application/json">{"base": "..", "features": [], "search": "../assets/javascripts/workers/search.b8dbb3d2.min.js", "translations": {"clipboard.copied": "Copied to clipboard", "clipboard.copy": "Copy to clipboard", "search.result.more.one": "1 more on this page", "search.result.more.other": "# more on this page", "search.result.none": "No matching documents", "search.result.one": "1 matching document", "search.result.other": "# matching documents", "search.result.placeholder": "Type to start searching", "search.result.term.missing": "Missing", "select.version": "Select version"}}</script>


       <script src="../assets/javascripts/bundle.081f42fc.min.js"></script>


   </body>
 </html>