File Handling in Web Applications

[Dilip H Pashupathi]

Hi,

I have requirement where the application provides the user the fecility of downloading an xml file in the format of ".tar.gz" format. This should be done such a way that the xml being downloaded should be placed in a temporary dierectory and then this direcoty should be added to the ".tar.gz" file. Once the file is created, the temporary directory should be deleted. I have tried using "org.apache.commons.io.FileUtils.deleteDirectory()" and also File - "delete()" method. But the problem I am encountering here is that once the folder is created and archive is also flushed through the output stream the folder is not getting deleted.

here is the peice of code that i have written for the above.

   ValueObject sendRecvVo = comsrv.getUDISenderReceiverIds(fldsVo);
                            	StringBuilder str = new StringBuilder(formVo.getSfield(RSMConstants.CONST_messageNumber));
                 				str.append("_");
                 				str.append(sendRecvVo.getSfield("SENDER_IID"));
                 				str.append("_");
                 				str.append(sendRecvVo.getSfield("RECEIVER_IID"));
                 				str.append("_");
                 				str.append("submission");
                 				fileName = str.toString();
                 				ValueObject tempVo = VoFactory.createVo();
                 				String destPath = fldsVo.getSfield(RSMConstants.CONST_messageNumber)+"/"+"spl"; 
                 				
                 				File f = new File(destPath);
                 				if(!f.exists()) {
                 					f.mkdirs();
                 				}
                 				
                 				FileOutputStream fos = new FileOutputStream(f.getAbsolutePath()+"/"+"submission.xml");
                 				fos.write(file);
                 				fos.flush();
                 				fos.close();
                 				tempVo.setSfield("destPath",fldsVo.getSfield(RSMConstants.CONST_messageNumber));
                 				tempVo.setSfield("fileName", fileName);
                 				
                                                createTarGZ(tempVo);
                                                 org.apache.commons.io.FileUtils.deleteDirectory(f);
                 				
                 				
                 				fileName = fileName +".tar.gz";
                 				
                 				FileInputStream fis = new FileInputStream(fileName);
                 				file = new byte[fis.available()];
                 				fis.read(file);
                 				fis.close();
                 				
                 				
                 				f = new File(fileName);
                 				if(f.exists()) {f.delete();};

                             -----------some more code
                                          if (headinfo.indexOf("MSIE") != -1){
                 			httpResponse.setContentType("application/*");
                	    }else{
                	        httpResponse.setContentType("application/x-filler");
                	    }
                 		httpResponse.setContentLength(file.length);
         	            httpResponse.setHeader("Content-Disposition", "attachment; filename=\"" + fileName +"\";");
         	            httpResponse.getOutputStream().write(file, 0, file.length);
         	            httpResponse.getOutputStream().flush();
         	            httpResponse.getOutputStream().close();
         	            File f = new File(fldsVo.getSfield(RSMConstants.CONST_messageNumber));
         	            org.apache.commons.io.FileUtils.deleteDirectory(f);
         	            
         	      		forward = null;

"createTarGz()" method

   public void createTarGZ(ValueObject criteriaVo) throws Exception {
		BufferedOutputStream outputBufferedStream = null;
		TarArchiveOutputStream tarOutputStream = null;
		String destPath = criteriaVo.getSfield("destPath");
		String destZipFilePath = criteriaVo.getSfield("fileName")+".tar.gz";
		FileOutputStream fos = null;
		try{
            
			fos = new FileOutputStream(new File(destZipFilePath));
            outputBufferedStream = new BufferedOutputStream(fos);
            tarOutputStream = new TarArchiveOutputStream(new GzipCompressorOutputStream(outputBufferedStream));
            tarOutputStream.setLongFileMode(tarOutputStream.LONGFILE_GNU);
            addFileToTarGz(tarOutputStream, destPath, "");
           
        } finally {
            tarOutputStream.finish();
            tarOutputStream.close();
            outputBufferedStream.close();
            fos.close();
        }

    }

    private void addFileToTarGz(TarArchiveOutputStream tarOutputStream, String path, String base) throws IOException {
        File file = new File(path);
        String fileName = base + file.getName();
        TarArchiveEntry tarEntry = new TarArchiveEntry(file, fileName);
        tarOutputStream.putArchiveEntry(tarEntry);
        
        if (file.isFile()) {
        	FileInputStream fis = new FileInputStream(file);
            IOUtils.copy(fis, tarOutputStream);
            tarOutputStream.closeArchiveEntry();
            fis.close();
        } else {
            tarOutputStream.closeArchiveEntry();
            File[] children = file.listFiles();
            if (children != null){
                for (File child : children) {
                    addFileToTarGz(tarOutputStream, child.getAbsolutePath(), fileName + "/");
                }
            }
        }
    }

And is it possible to create the tar.gz file without having to create a physical directories?



Please Help

Regards
Dilip H P