如何修复：DOCX 到 HTML 的 DOCX4J 错误 (java.lang.NullPointerException)答案

【问题标题】：How to fix: DOCX to HTML with DOCX4J error (java.lang.NullPointerException)如何修复：DOCX 到 HTML 的 DOCX4J 错误 (java.lang.NullPointerException)
【发布时间】：2020-12-04 10:34:07
【问题描述】：

我正在尝试使用 DOCX4j、Java 11、Spring boot 2.3.5、Ubuntu 18.04.5 将 DOCX 转换为 HTML，并且我正在 tomcat 9 上运行我的 .WAR 文件。

当我运行代码时，我得到了这个错误。我该如何解决这个问题？

我的代码

参考：

export HTML to DOCX with Docx4j

https://github.com/plutext/docx4j-ImportXHTML/blob/master/src/samples/java/org/docx4j/samples/DocxToXhtmlAndBack.java

 WordprocessingMLPackage wordMLPackage = WordprocessingMLPackage.load(new File(source));

 HTMLSettings htmlSettings = Docx4J.createHTMLSettings();
 htmlSettings.setWmlPackage(wordMLPackage);
 htmlSettings.setImageDirPath("temp_images");
 htmlSettings.setImageTargetUri("temp_images");
 htmlSettings.setImageIncludeUUID(false);

 boolean nestLists = false;
 if (nestLists) {
     SdtWriter.registerTagHandler("HTML_ELEMENT", new SdtToListSdtTagHandler());
 } else {
     // convert numberings to plain text
     htmlSettings.getFeatures().remove(ConversionFeatures.PP_HTML_COLLECT_LISTS);
 } 

 OutputStream os = new java.io.FileOutputStream(dest);
 Docx4J.toHTML(htmlSettings, os, Docx4J.FLAG_EXPORT_PREFER_XSL);

Pom.xml：

   <dependency>
        <groupId>org.docx4j</groupId>
        <artifactId>docx4j</artifactId>
        <version>6.1.2</version>
    </dependency>

    <dependency>
        <groupId>org.docx4j</groupId>
        <artifactId>docx4j-JAXB-ReferenceImpl</artifactId>
        <version>11.2.5</version>
    </dependency> 

    <dependency>
        <groupId>org.docx4j</groupId>
        <artifactId>docx4j-MOXy-JAXBContext</artifactId>
        <version>6.0.0</version>
    </dependency>
    <dependency>
        <groupId>org.eclipse.persistence</groupId>
        <artifactId>org.eclipse.persistence.moxy</artifactId>
        <version>2.7.7</version>
    </dependency>
    <dependency>
        <groupId>org.eclipse.persistence</groupId>
        <artifactId>eclipselink</artifactId>
        <version>2.7.7</version>
    </dependency>
    <dependency>
        <groupId>fr.opensagres.xdocreport</groupId>
        <artifactId>fr.opensagres.xdocreport.document.docx</artifactId>
        <version>2.0.2</version>
    </dependency>
    <dependency>
        <groupId>fr.opensagres.xdocreport</groupId>
        <artifactId>fr.opensagres.xdocreport.template.freemarker</artifactId>
        <version>2.0.2</version>
    </dependency>
    <dependency>
        <groupId>fr.opensagres.xdocreport</groupId>
        <artifactId>fr.opensagres.xdocreport.converter.docx.xwpf</artifactId>
        <version>2.0.2</version>
    </dependency>

日志文件：

org.docx4j.openpackaging.exceptions.Docx4JException: Exception exporting package
org.docx4j.openpackaging.exceptions.Docx4JException: Exception exporting package
        at org.docx4j.convert.out.common.AbstractExporter.export(AbstractExporter.java:106)
        at org.docx4j.Docx4J.toHTML(Docx4J.java:830)
        at com.home.converter.Xhtmlconv.startConveter(Xhtmlconv.java:141)
        at com.home.controller.myproject.shephard.GetController.getStartGenerateXhtml(GetController.java:1377)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:566)
        at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
        at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:878)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:792)
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
        at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:126)
        at org.springframework.boot.web.servlet.support.ErrorPageFilter.access$000(ErrorPageFilter.java:64)
        at org.springframework.boot.web.servlet.support.ErrorPageFilter$1.doFilterInternal(ErrorPageFilter.java:101)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
        at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:119)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
        at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373)
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590)
        at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
        at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: java.lang.NullPointerException
        at org.docx4j.openpackaging.parts.WordprocessingML.ObfuscatedFontPart.deleteEmbeddedFontTempFiles(ObfuscatedFontPart.java:263)
        at org.docx4j.openpackaging.parts.WordprocessingML.FontTablePart.deleteEmbeddedFontTempFiles(FontTablePart.java:161)
        at org.docx4j.convert.out.common.AbstractExporter.export(AbstractExporter.java:90)
        ... 61 more

编辑：我尝试在 tomcat 9、Windows 10 上运行相同的 WAR，一切正常。有趣...但是如何在 linux-tomcat 上解决这个问题？（检查了tomcat / linux，没问题，没有损坏）

【问题讨论】：

请尝试更新的 docx4j，例如 8.2.4。
NPE 至少应该位于不同的行号。
所以请告知，使用 8.2.6
看起来您的 tmpFontDir 为空。 github.com/plutext/docx4j/blob/master/docx4j-core/src/main/java/… 设置它。考虑设置属性'docx4j.openpackaging.parts.WordprocessingML.ObfuscatedFontPart.tmpFontDir'？
尝试 TOMCAT_HOME/temp （替换其中的实际路径）

标签： java spring xhtml docx docx4j

【解决方案1】：

看起来您的 tmpFontDir 为空。

https://github.com/plutext/docx4j/blob/master/docx4j-core/src/main/java/org/docx4j/openpackaging/parts/AbstractFontPart.java#L66 设置它。

考虑设置属性docx4j.openpackaging.parts.WordprocessingML.ObfuscatedFontPart.tmpFontDir

由于您使用的是 Tomcat，请将其设置为 TOMCAT_HOME/temp（替换其中的实际路径）。

【讨论】：