POI操作Excel报错java.lang.NoSuchMethodError

1、检查报错日志如下

2、定位错误1、可能是编码出问题，检查编码

3、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" ));

4、检查导入poi的包是否存在多个版本，删除多余版本。

5、<dependency> <groupId>org.apache.poi</groupId> <artifactId>poi-ooxml</artifactId> <version>3.17</version> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi-ooxml-schemas</artifactId> <version>3.17</version> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi</artifactId> <version>3.17</version> </dependency>

6、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、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、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。