spring boot 项目打成jar包后读取文件问题

￡神魔★判官ぃ 2022-10-08 00:55 179阅读 0赞

> java.io.FileNotFoundException: class path resource \[xxx.xls\]  
> cannot be resolved to absolute file path because it does not reside in the file system: jar:file:/D:/新建文件夹/xxx.jar!/BOOT-INF/classes!/export/xxx.xls  
> at org.springframework.util.ResourceUtils.getFile(ResourceUtils.java:217)

> 在war包运行情况下是没问题的，路径其实是对的，spring是不允许直接访问jar包内的文件的，所以会报错，然后改写下读取文件的方式

*  精简的老代码方式
    
        ClassPathResource resource = new ClassPathResource("XXX.xls");
          File file = resource.getFile();
 *  修改后的精简代码
    
        ClassPathResource resource = new ClassPathResource("application.yml");
          InputStream inputStream = resource.getInputStream();
 *  笔者老代码
    
        public String generateExcel(String sourceFileName, String destFileName, Map<String, Object> params) throws Exception{ 
                  XLSTransformer transformer = new XLSTransformer();
          
          // URL url = this.getClass().getClassLoader().getResource("");
          //
          // assert url != null;
                  ClassPathResource resource = new ClassPathResource(EXPORT_RESOURCE_PATH + sourceFileName);
          
                  transformer.transformXLS( resource.getFile().getPath(), params, TMP_DIR + destFileName);
                  return TMP_DIR + destFileName;
              }
 *  笔者新代码
    
        public String generateExcel(String sourceFileName, String destFileName, Map<String, Object> params) throws Exception{ 
          // XLSTransformer transformer = new XLSTransformer();
          
          // URL url = this.getClass().getClassLoader().getResource("");
          //
          // assert url != null;
                  ClassPathResource resource = new ClassPathResource(EXPORT_RESOURCE_PATH + sourceFileName);
          
                  InputStream inputStream = resource.getInputStream();
          
          
          // transformer.transformXLS( resource.getFile().getPath(), params, TMP_DIR + destFileName);
                  transformXLS4Jar( inputStream, params, TMP_DIR + destFileName);
                  return TMP_DIR + destFileName;
              }
        
            public  void transformXLS4Jar(InputStream is, Map beanParams, String destFilePath) throws ParsePropertyException, IOException, InvalidFormatException { 
              XLSTransformer xlsTransformer = new XLSTransformer();
              org.apache.poi.ss.usermodel.Workbook workbook = xlsTransformer.transformXLS(is, beanParams);
              OutputStream os = new BufferedOutputStream(new FileOutputStream(destFilePath));
              workbook.write(os);
              is.close();
              os.flush();
              os.close();
          }