优化Docker部署：解决Java应用ExcelGenerateException并提速镜像构建

在开发和部署应用时，经常会遇到在本地环境运行正常，但迁移到Docker容器后出现特定错误的情况。本篇博客将聚焦于解决一个具体问题：当使用Docker部署包含Excel生成功能的Java应用程序时，遇到ExcelGenerateException的排查与解决方法。

1. 问题现象

• 本地环境：应用程序能够顺利生成Excel文件，无任何异常。
• Docker环境：部署相同的应用程序后，在执行Excel生成操作时，系统抛出ExcelGenerateException。

例如：

Dockerfile文件：

FROM java:8-alpine
COPY ./docker-demo.jar /tmp/demo-0.0.1-SNAPSHOT.jar
EXPOSE 8090
ENTRYPOINT java -jar /tmp/demo-0.0.1-SNAPSHOT.jar

部署后报错： 

com.alibaba.excel.exception.ExcelGenerateException: Create workbook failureat com.alibaba.excel.context.WriteContextImpl.<init>(WriteContextImpl.java:88) ~[easyexcel-3.0.0-beta1.jar!/:na]at com.alibaba.excel.write.ExcelBuilderImpl.<init>(ExcelBuilderImpl.java:36) ~[easyexcel-3.0.0-beta1.jar!/:na]at com.alibaba.excel.ExcelWriter.<init>(ExcelWriter.java:39) ~[easyexcel-3.0.0-beta1.jar!/:na]at com.alibaba.excel.write.builder.ExcelWriterBuilder.build(ExcelWriterBuilder.java:104) ~[easyexcel-3.0.0-beta1.jar!/:na]at com.zjp.demo.service.impl.ExportImpl.export(ExportImpl.java:632) ~[classes!/:na]at com.zjp.demo.service.impl.ExportImpl$$FastClassBySpringCGLIB$$93118298.invoke(<generated>) ~[classes!/:na]at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.CglibAopProxy.invokeMethod(CglibAopProxy.java:386) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.CglibAopProxy.access$000(CglibAopProxy.java:85) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:704) ~[spring-aop-5.3.23.jar!/:5.3.23]at com.zjp.demo.service.impl.ExportImpl$$EnhancerBySpringCGLIB$$df7a6b3d.riskSurveyExport(<generated>) ~[classes!/:na]at com.zjp.demo.controller.StatisController.riskSurveyExport(StatisController.java:97) ~[classes!/:na]at com.zjp.demo.controller.StatisController$$FastClassBySpringCGLIB$$3f0e2a16.invoke(<generated>) ~[classes!/:na]at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:89) ~[spring-aop-5.3.23.jar!/:5.3.23]at com.zjp.demo.aop.LogRecordAspect.doAround(LogRecordAspect.java:65) ~[classes!/:na]at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_212]at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_212]at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_212]at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_212]at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:634) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:624) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:72) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.23.jar!/:5.3.23]at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708) ~[spring-aop-5.3.23.jar!/:5.3.23]at com.zjp.demo.controller.StatisController$$EnhancerBySpringCGLIB$$bebb4c75.riskSurveyExport(<generated>) ~[classes!/:na]at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_212]at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_212]at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_212]at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_212]at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-5.3.23.jar!/:5.3.23]at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150) ~[spring-web-5.3.23.jar!/:5.3.23]at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-5.3.23.jar!/:5.3.23]at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.3.23.jar!/:5.3.23]at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) ~[spring-webmvc-5.3.23.jar!/:5.3.23]at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.3.23.jar!/:5.3.23]at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1071) ~[spring-webmvc-5.3.23.jar!/:5.3.23]at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:964) ~[spring-webmvc-5.3.23.jar!/:5.3.23]at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.23.jar!/:5.3.23]at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) ~[spring-webmvc-5.3.23.jar!/:5.3.23]at javax.servlet.http.HttpServlet.service(HttpServlet.java:668) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at javax.servlet.http.HttpServlet.service(HttpServlet.java:655) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.23.jar!/:5.3.23]at javax.servlet.http.HttpServlet.service(HttpServlet.java:772) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:211) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.inforsuite.websocket.server.WsFilter.doFilter(WsFilter.java:53) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:180) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:91) [spring-web-5.3.23.jar!/:5.3.23]at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.23.jar!/:5.3.23]at com.cvicse.bixi.kernel.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:180) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:96) [spring-boot-actuator-2.6.13.jar!/:2.6.13]at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.23.jar!/:5.3.23]at com.cvicse.bixi.kernel.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:180) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) [spring-web-5.3.23.jar!/:5.3.23]at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.23.jar!/:5.3.23]at com.cvicse.bixi.kernel.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:180) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.StandardWrapperValve.invoke(StandardWrapperValve.java:178) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.StandardContextValve.invoke(StandardContextValve.java:92) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:527) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.StandardHostValve.invoke(StandardHostValve.java:133) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.kernel.StandardEngineValve.invoke(StandardEngineValve.java:77) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.connector.BixiConnectorAdapter.service(BixiConnectorAdapter.java:341) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.http11.Http11Processor.service(Http11Processor.java:363) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.AbstractProcessorLight.process(AbstractProcessorLight.java:64) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.bixi.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:958) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.inforsuite.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1757) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.inforsuite.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.inforsuite.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1196) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.inforsuite.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:664) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at com.cvicse.inforsuite.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [spring-boot-starter-inforsuite-10.0.2.4.jar!/:na]at java.lang.Thread.run(Thread.java:748) [na:1.8.0_212]
Caused by: java.lang.NullPointerException: nullat sun.awt.FontConfiguration.getVersion(FontConfiguration.java:1264) ~[na:1.8.0_212]at sun.awt.FontConfiguration.readFontConfigFile(FontConfiguration.java:219) ~[na:1.8.0_212]at sun.awt.FontConfiguration.init(FontConfiguration.java:107) ~[na:1.8.0_212]at sun.awt.X11FontManager.createFontConfiguration(X11FontManager.java:774) ~[na:1.8.0_212]at sun.font.SunFontManager$2.run(SunFontManager.java:431) ~[na:1.8.0_212]at java.security.AccessController.doPrivileged(Native Method) ~[na:1.8.0_212]at sun.font.SunFontManager.<init>(SunFontManager.java:376) ~[na:1.8.0_212]at sun.awt.FcFontManager.<init>(FcFontManager.java:35) ~[na:1.8.0_212]at sun.awt.X11FontManager.<init>(X11FontManager.java:57) ~[na:1.8.0_212]at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_212]at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_212]at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_212]at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_212]at java.lang.Class.newInstance(Class.java:442) ~[na:1.8.0_212]at sun.font.FontManagerFactory$1.run(FontManagerFactory.java:83) ~[na:1.8.0_212]at java.security.AccessController.doPrivileged(Native Method) ~[na:1.8.0_212]at sun.font.FontManagerFactory.getInstance(FontManagerFactory.java:74) ~[na:1.8.0_212]at java.awt.Font.getFont2D(Font.java:491) ~[na:1.8.0_212]at java.awt.Font.canDisplayUpTo(Font.java:2060) ~[na:1.8.0_212]at java.awt.font.TextLayout.singleFont(TextLayout.java:470) ~[na:1.8.0_212]at java.awt.font.TextLayout.<init>(TextLayout.java:531) ~[na:1.8.0_212]at org.apache.poi.ss.util.SheetUtil.getDefaultCharWidth(SheetUtil.java:273) ~[poi-4.1.2.jar!/:4.1.2]at org.apache.poi.xssf.streaming.AutoSizeColumnTracker.<init>(AutoSizeColumnTracker.java:117) ~[poi-ooxml-4.1.2.jar!/:4.1.2]at org.apache.poi.xssf.streaming.SXSSFSheet.<init>(SXSSFSheet.java:82) ~[poi-ooxml-4.1.2.jar!/:4.1.2]at org.apache.poi.xssf.streaming.SXSSFWorkbook.createAndRegisterSXSSFSheet(SXSSFWorkbook.java:684) ~[poi-ooxml-4.1.2.jar!/:4.1.2]at org.apache.poi.xssf.streaming.SXSSFWorkbook.<init>(SXSSFWorkbook.java:247) ~[poi-ooxml-4.1.2.jar!/:4.1.2]at org.apache.poi.xssf.streaming.SXSSFWorkbook.<init>(SXSSFWorkbook.java:211) ~[poi-ooxml-4.1.2.jar!/:4.1.2]at org.apache.poi.xssf.streaming.SXSSFWorkbook.<init>(SXSSFWorkbook.java:186) ~[poi-ooxml-4.1.2.jar!/:4.1.2]at com.alibaba.excel.util.WorkBookUtil.createWorkBook(WorkBookUtil.java:42) ~[easyexcel-3.0.0-beta1.jar!/:na]at com.alibaba.excel.context.WriteContextImpl.<init>(WriteContextImpl.java:86) ~[easyexcel-3.0.0-beta1.jar!/:na]... 83 common frames omitted

2. 原因分析

该异常通常源于容器环境中缺少必要的字体配置和支持库，影响了如Apache POI等Excel处理库的正常运作。

3. 解决策略：修改Dockerfile

1. 选做：通过添加 RUN sed -i 's/dl-cdn.alpinelinux.org/mirrors.aliyun.com/g' /etc/apk/repositories 命令替换默认的Alpine Linux软件包源为阿里云镜像站，显著提升软件包下载速度。
2. 选做：更新软件包索引：RUN apk update
3. 核心：在Dockerfile中，通过添加 RUN apk add --no-cache fontconfig ttf-dejavu 命令找到或添加一个合适的环节来安装fontconfig和ttf-dejavu包。这些包提供了必要的字体支持，有助于避免Excel生成时的异常。

最终修改方案为：

FROM java:8-alpine# 更换默认软件源为阿里云镜像站
RUN sed -i 's/dl-cdn.alpinelinux.org/mirrors.aliyun.com/g' /etc/apk/repositories# 更新软件包索引
RUN apk update# 安装字体和配置库
RUN apk add --no-cache fontconfig ttf-dejavuCOPY ./docker-demo.jar /tmp/demo-0.0.1-SNAPSHOT.jar
EXPOSE 8090
ENTRYPOINT java -jar /tmp/demo-0.0.1-SNAPSHOT.jar