Spring Cloud2 Zipkin集成之异常排错记

时间 2019-11-06

标签 spring cloud2 cloud zipkin 集成异常排错栏目 Spring 繁體版

原文原文链接

前言

此文只是记录在实践 Spring Cloud构建微服务架构：分布式服务跟踪（整合zipkin）【Dalston版】过程当中遇到问题的解决过程，因为文章是1.x版本，我使用的为最新2.1.7.RELEASE版本，在后续解决问题查资料过程当中了解到，关于 Zipkin 的服务端，在使用 Spring Boot 2.x 版本后，官方就不推荐自行定制编译了，反而是直接提供了编译好的 jar 包来给咱们使用，详情请看 upgrade to Spring Boot 2.0 NoClassDefFoundError UndertowEmbeddedServletContainerFactory · Issue #1962 · openzipkin/zipkin · GitHub。因此若是是实践Spring Cloud2 Zipkin集成的话，可参考以下资料：html

spring boot 2.0.3+spring cloud （Finchley）七、服务链路追踪Spring Cloud Sleuthjava

springboot新版本(2.1.0)、springcloud新版本(Greenwich.M1)实现链路追踪的一些坑mysql

以下内容做为记录，你们若是碰上相关异常，能参考一二即好git

1、组件引入配置

Spring Cloud2 Zipkin集成实践Spring Cloud构建微服务架构：分布式服务跟踪（整合zipkin）【Dalston版】，ｐｏｍ．ｘｍｌ配置以下：github

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  
  	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.1.7.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	
  <groupId>com.dreamer.demo.springcloud</groupId>
  <artifactId>zipkin-server</artifactId>
  <packaging>jar</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>zipkin-server Maven Webapp</name>
  <url>http://maven.apache.org</url>
  
  	<properties>
	    <maven.compiler.source>11</maven.compiler.source>
		<maven.compiler.target>11</maven.compiler.target>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>11</java.version>
		<spring-cloud.version>Greenwich.SR2</spring-cloud.version>
		<zipkin.version>2.12.9</zipkin.version>
	</properties>
	
  <dependencies>
	  <dependency>
	  	<groupId>io.zipkin.java</groupId>
	  	<artifactId>zipkin-server</artifactId>
	  	<version>${zipkin.version}</version>
	  </dependency>
	  
	  <dependency>
	  	<groupId>io.zipkin.java</groupId>
	  	<artifactId>zipkin-autoconfigure-ui</artifactId>
	  	<version>${zipkin.version}</version>
	  </dependency>
  </dependencies>

  <build>
    <finalName>zipkin-server</finalName>
  </build>
</project>

2、web应用服务未集成异常

启动报以下异常：web

org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:156) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:743) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:390) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:312) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1214) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1203) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at com.dreamer.Application.main(Application.java:13) [classes/:?]
Caused by: org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.getWebServerFactory(ServletWebServerApplicationContext.java:203) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:179) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	... 8 more

查看异常信息 Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean spring

【因为缺乏ServletWebServerFactory bean，没法启动ServletWebServerApplicationContext】sql

咱们知道spring boot默认应用服务器是ｔｏｍｃａｔ，这里说缺乏，查找包依赖，确实是没有引入ｔｏｍｃａｔ，把spring-boot-starter-tomcat引入，从新启动，上面异常解决。apache

3、'armeriaServer' 初始实例化空指针

但有新的异常，以下：json

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'armeriaServer' defined in class path resource [com/linecorp/armeria/spring/ArmeriaAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.linecorp.armeria.server.Server]: Factory method 'armeriaServer' threw exception; nested exception is java.lang.NullPointerException
	at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:627) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:607) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1321) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1160) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:845) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:877) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:743) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:390) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:312) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1214) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1203) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
	at com.dreamer.Application.main(Application.java:13) [classes/:?]
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.linecorp.armeria.server.Server]: Factory method 'armeriaServer' threw exception; nested exception is java.lang.NullPointerException
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:622) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	... 19 more
Caused by: java.lang.NullPointerException
	at zipkin2.autoconfigure.ui.ZipkinUiAutoConfiguration.lambda$uiServerConfigurator$0(ZipkinUiAutoConfiguration.java:179) ~[zipkin-autoconfigure-ui-2.12.9.jar:?]
	at com.linecorp.armeria.spring.ArmeriaAutoConfiguration.lambda$armeriaServer$0(ArmeriaAutoConfiguration.java:111) ~[armeria-spring-boot-autoconfigure-0.83.0.jar:?]
	at java.util.ArrayList.forEach(ArrayList.java:1540) ~[?:?]
	at com.linecorp.armeria.spring.ArmeriaAutoConfiguration.lambda$armeriaServer$1(ArmeriaAutoConfiguration.java:110) ~[armeria-spring-boot-autoconfigure-0.83.0.jar:?]
	at java.util.Optional.ifPresent(Optional.java:183) ~[?:?]
	at com.linecorp.armeria.spring.ArmeriaAutoConfiguration.armeriaServer(ArmeriaAutoConfiguration.java:109) ~[armeria-spring-boot-autoconfigure-0.83.0.jar:?]
	at com.linecorp.armeria.spring.ArmeriaAutoConfiguration$$EnhancerBySpringCGLIB$$7013b1d3.CGLIB$armeriaServer$0(<generated>) ~[armeria-spring-boot-autoconfigure-0.83.0.jar:?]
	at com.linecorp.armeria.spring.ArmeriaAutoConfiguration$$EnhancerBySpringCGLIB$$7013b1d3$$FastClassBySpringCGLIB$$893247fb.invoke(<generated>) ~[armeria-spring-boot-autoconfigure-0.83.0.jar:?]
	at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:244) ~[spring-core-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:363) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at com.linecorp.armeria.spring.ArmeriaAutoConfiguration$$EnhancerBySpringCGLIB$$7013b1d3.armeriaServer(<generated>) ~[armeria-spring-boot-autoconfigure-0.83.0.jar:?]
	at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?]
	at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:?]
	at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]
	at java.lang.reflect.Method.invoke(Method.java:566) ~[?:?]
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:622) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
	... 19 more

此处异常信息为：Error creating bean with name 'armeriaServer' defined in class path resource [com/linecorp/armeria/spring/ArmeriaAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.linecorp.armeria.server.Server]: Factory method 'armeriaServer' threw exception; nested exception is java.lang.NullPointerException

从异常信息能够看出建立　armeriaServer　失败，有　java.lang.NullPointerException，但具体是哪里致使NullPointerException，在异常信息上看不出来，因而想到把日志设置为ＤＥＢＵＧ，打印详细日志，看可否查看到具体java.lang.NullPointerException缘由。

4、添加logback配置

添加logback-spring.xml文件至项目resources中，配置内容以下：

<?xml version="1.0" encoding="UTF-8"?>
<configuration  scan="true" scanPeriod="60 seconds" debug="false">
    <contextName>logback</contextName>
    <property name="log.path" value="H:\\project-log\\springcloud\\logback.log" />
    <!--输出到控制台-->
    <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
       <!-- <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>ERROR</level>
        </filter>-->
        <encoder>
            <pattern>%d{HH:mm:ss.SSS} %contextName [%thread] %-5level %logger{36} - %msg%n</pattern>
        </encoder>
    </appender>

    <!--输出到文件-->
    <appender name="file" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${log.path}</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <fileNamePattern>logback.%d{yyyy-MM-dd}.log</fileNamePattern>
        </rollingPolicy>
        <encoder>
            <pattern>%d{HH:mm:ss.SSS} %contextName [%thread] %-5level %logger{36} - %msg%n</pattern>
        </encoder>
    </appender>

    <root level="DEBUG">
        <appender-ref ref="console" />
        <appender-ref ref="file" />
    </root>
</configuration>

从新启动项目，未见打印DEBUG信息。因而想到是否未引入/集成logback组件，但spring boot web默认日志组件为logback，经查引入依赖，确实是未有logback的jar。也想到上面咱们未引入spring-boot-starter-web。

5、引入logback组件

因而我把spring-boot-starter-tomcat去掉【这个是spring-boot-starter-web默认引入】，引入spring-boot-starter-web，pom.xml配置以下：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  
  	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.1.7.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	
  <groupId>com.dreamer.demo.springcloud</groupId>
  <artifactId>zipkin-server</artifactId>
  <packaging>jar</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>zipkin-server Maven Webapp</name>
  <url>http://maven.apache.org</url>
  
  	<properties>
	    <maven.compiler.source>11</maven.compiler.source>
		<maven.compiler.target>11</maven.compiler.target>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>11</java.version>
		<spring-cloud.version>Greenwich.SR2</spring-cloud.version>
		<zipkin.version>2.12.9</zipkin.version>
	</properties>
	
  <dependencies>
	  <dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-web</artifactId>
	  </dependency>

	  <dependency>
	  	<groupId>io.zipkin.java</groupId>
	  	<artifactId>zipkin-server</artifactId>
	  	<version>${zipkin.version}</version>
	  </dependency>
	  
	  <dependency>
	  	<groupId>io.zipkin.java</groupId>
	  	<artifactId>zipkin-autoconfigure-ui</artifactId>
	  	<version>${zipkin.version}</version>
	  </dependency>
  </dependencies>
  <build>
    <finalName>zipkin-server</finalName>
  </build>
</project>

重启项目，DEBUG日志正常输出，并且有看到 java.lang.NullPointerException 缘由，详细异常以下：

16:19:45.452 logback [main] DEBUG o.s.b.diagnostics.FailureAnalyzers - FailureAnalyzer org.springframework.boot.autoconfigure.jdbc.HikariDriverConfigurationFailureAnalyzer@a826ff8 failed
java.lang.TypeNotPresentException: Type org.springframework.jdbc.CannotGetJdbcConnectionException not present
	at java.base/sun.reflect.generics.factory.CoreReflectionFactory.makeNamedType(CoreReflectionFactory.java:117)
	at java.base/sun.reflect.generics.visitor.Reifier.visitClassTypeSignature(Reifier.java:125)
	at java.base/sun.reflect.generics.tree.ClassTypeSignature.accept(ClassTypeSignature.java:49)
	at java.base/sun.reflect.generics.visitor.Reifier.reifyTypeArguments(Reifier.java:68)
	at java.base/sun.reflect.generics.visitor.Reifier.visitClassTypeSignature(Reifier.java:138)
	at java.base/sun.reflect.generics.tree.ClassTypeSignature.accept(ClassTypeSignature.java:49)
	at java.base/sun.reflect.generics.repository.ClassRepository.computeSuperclass(ClassRepository.java:104)
	at java.base/sun.reflect.generics.repository.ClassRepository.getSuperclass(ClassRepository.java:86)
	at java.base/java.lang.Class.getGenericSuperclass(Class.java:950)
	at org.springframework.core.ResolvableType.getSuperType(ResolvableType.java:466)
	at org.springframework.core.ResolvableType.as(ResolvableType.java:455)
	at org.springframework.core.ResolvableType.forClass(ResolvableType.java:1037)
	at org.springframework.boot.diagnostics.AbstractFailureAnalyzer.getCauseType(AbstractFailureAnalyzer.java:56)
	at org.springframework.boot.diagnostics.AbstractFailureAnalyzer.analyze(AbstractFailureAnalyzer.java:33)
	at org.springframework.boot.diagnostics.FailureAnalyzers.analyze(FailureAnalyzers.java:110)
	at org.springframework.boot.diagnostics.FailureAnalyzers.reportException(FailureAnalyzers.java:103)
	at org.springframework.boot.SpringApplication.reportFailure(SpringApplication.java:812)
	at org.springframework.boot.SpringApplication.handleRunFailure(SpringApplication.java:797)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:322)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1214)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1203)
	at com.dreamer.Application.main(Application.java:13)
Caused by: java.lang.ClassNotFoundException: org.springframework.jdbc.CannotGetJdbcConnectionException
	at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
	at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
	at java.base/java.lang.Class.forName0(Native Method)
	at java.base/java.lang.Class.forName(Class.java:398)
	at java.base/sun.reflect.generics.factory.CoreReflectionFactory.makeNamedType(CoreReflectionFactory.java:114)
	... 21 common frames omitted

6、添加mysql组件/配置

组件

<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>8.0.14</version>
		</dependency>


		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jdbc</artifactId>
		</dependency>

配置

spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://xxx.xxx.xxx.xxx:3306/test?autoReconnect=true&useUnicode=true&characterEncoding=utf-8&allowMultiQueries=true
spring.datasource.username=xxxxxx
spring.datasource.password=xxxxxx

从新启动服务，java.lang.TypeNotPresentException: Type org.springframework.jdbc.CannotGetJdbcConnectionException 消失，但org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'armeriaServer' 异常仍是存在，这就有点郁闷了，直接根据异常信息查询资料，未见相应的解决方案。哪就简单点，直接撸源代码查下缘由。根据如下异常信息：

Caused by: java.lang.NullPointerException
at zipkin2.autoconfigure.ui.ZipkinUiAutoConfiguration.lambda$uiServerConfigurator$0(ZipkinUiAutoConfiguration.java:179) ~[zipkin-autoconfigure-ui-2.12.9.jar:?]

at com.linecorp.armeria.spring.ArmeriaAutoConfiguration.lambda$armeriaServer$0(ArmeriaAutoConfiguration.java:111) ~[armeria-spring-boot-autoconfigure-0.83.0.jar:?]

直接点击进入ZipkinUiAutoConfiguration.java:179，看到代码以下：

Compression compression = compressionProperties.getCompression();
if (compression.getEnabled()) {
sb.decorator(contentEncodingDecorator(compression));
}

报错代码为：if (compression.getEnabled()) { 这一行。一看就能够明白，是 compression 对象为空致使。但为何会为空？怎么解决，就得看看代码上下文。当前方法完整代码以下：

@Bean @Lazy ArmeriaServerConfigurator uiServerConfigurator(
    CompressionProperties compressionProperties,
    IndexSwitchingService indexSwitchingService) throws IOException {
    ServerCacheControl maxAgeYear =
      new ServerCacheControlBuilder().maxAgeSeconds(TimeUnit.DAYS.toSeconds(365)).build();
    Service<HttpRequest, HttpResponse> uiFileService =
      HttpFileServiceBuilder.forClassPath("zipkin-ui").cacheControl(maxAgeYear).build()
        .orElse(
          HttpFileServiceBuilder.forClassPath("zipkin-lens").cacheControl(maxAgeYear).build());

    byte[] config = new ObjectMapper().writeValueAsBytes(ui);
    return sb -> {
      sb.service("/zipkin/config.json", HttpFileBuilder.of(HttpData.of(config))
        .cacheControl(new ServerCacheControlBuilder().maxAgeSeconds(600).build())
        .contentType(MediaType.JSON_UTF_8)
        .build()
        .asService());

      sb.serviceUnder("/zipkin/", uiFileService);

      // TODO This approach requires maintenance when new UI routes are added. Change to the following:
      // If the path is a a file w/an extension, treat normally.
      // Otherwise instead of returning 404, forward to the index.
      // See https://github.com/twitter/finatra/blob/458c6b639c3afb4e29873d123125eeeb2b02e2cd/http/src/main/scala/com/twitter/finatra/http/response/ResponseBuilder.scala#L321
      sb.service("/zipkin/", indexSwitchingService)
        .service("/zipkin/index.html", indexSwitchingService)
        .service("/zipkin/traces/{id}", indexSwitchingService)
        .service("/zipkin/dependency", indexSwitchingService)
        .service("/zipkin/traceViewer", indexSwitchingService);

      sb.service("/favicon.ico", new RedirectService(HttpStatus.FOUND, "/zipkin/favicon.ico"))
        .service("/", new RedirectService(HttpStatus.FOUND, "/zipkin/"))
        .service("/zipkin", new RedirectService(HttpStatus.FOUND, "/zipkin/"));

      Compression compression = compressionProperties.getCompression();
      if (compression.getEnabled()) {
        sb.decorator(contentEncodingDecorator(compression));
      }
    };
  }

经一步步代码查看，能够发现 Compression 对象中有一个属性默认值为false[ private boolean enabled = false;]，经查资料这个是配置应用服务器压缩的，详情配置说明可见：SpringBoot配置属性之Server，我试着把此属性值配置为打开，重启服务终于没见异常了，好J-DONG, 配置以下：

server.compression.enabled=true

不过在查资料过程当中，从github看到一个配置，我试着配置了下，是能够正常运行的。连接以下：

https://github.com/line/armeria-examples/blob/master/spring-boot-minimal/src/main/resources/config/application.yml

spring.main.web-application-type: none

此配置指定当前spring boot为非web应用，至于为什么这样配置？zipkin不就是web应用服务？这里就不讨论

服务启动正常，访问http://127.0.0.1:8080，会跳转至http://127.0.0.1:8080/zipkin/并看到管理界面，K.O

项目源代码详见：

https://gitee.com/showlike/springcloud2-demo/tree/master/zipkin-server

参考资料

SpringBoot 2.0.0新版和SpringBoot1.5.2版本中Tomcat配置的差异