使用poi做Excel导出功能时，本地服务器正常，服务器下载为空白文档。检查服务器日志时报错：java.lang.NoSuchMethodError: org.apache.poi.util.POILogger.log(I[Ljava/lang/Object;)V工具/原料morepoi jar包maven项目方法/步骤1/8分步阅读

检查报错日志如下

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定位错误

1、可能是编码出问题，检查编码

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生成EXCEL文件类是否有如下编码：

response.setContentType(application/x-msdownload);

response.setCharacterEncoding(utf-8);

response.setHeader(Content-Disposition, attachment;filename= + new String( fileName.getBytes(gb2312), ISO8859-1 ));

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2、检查导入poi的包是否存在多个版本，删除多余版本。

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dependency

groupIdorg.apache.poi/groupId

artifactIdpoi-ooxml/artifactId

version3.17/version

/dependency

dependency

groupIdorg.apache.poi/groupId

artifactIdpoi-ooxml-schemas/artifactId

version3.17/version

/dependency

dependency

groupIdorg.apache.poi/groupId

artifactIdpoi/artifactId

version3.17/version

/dependency

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如果不确定自己引用的是哪个包，可以用一下代码检测class文件走哪个jar包

7/8

检测class文件代码：

ClassLoader classloader =

org.apache.poi.poifs.filesystem.POIFSFileSystem.class.getClassLoader();

URL res = classloader.getResource(

org/apache/poi/poifs/filesystem/POIFSFileSystem.class);

String path = res.getPath();

System.out.println(POI Core came from + path);

classloader = org.apache.poi.POIXMLDocument.class.getClassLoader();

res = classloader.getResource(org/apache/poi/POIXMLDocument.class);

path = res.getPath();

System.out.println(POI OOXML came from + path);

classloader = org.apache.poi.hslf.HSLFSlideShow.class.getClassLoader();

res = classloader.getResource(org/apache/poi/hslf/HSLFSlideShow.class);

path = res.getPath();

System.out.println(POI Scratchpad came from + path);

8/8

将旧的jar从Java build path中删除掉，把workspace里面的包删了再把project clean一下，然后重新部署。