Develop Reference

Jar executable of spring app file upload failed?

This spring app performs simple file upload,
here's the controller class
#Override
public String fileUpload(MultipartFile file) {
try{
// save uploaded image to images folder in root dir
Files.write(Paths.get("images/"+ file.getOriginalFilename()), file.getBytes());
// perform some tasks on image
return "";
} catch (IOException ioException) {
return "File upload has failed.";
} finally {
Files.delete(Paths.get("images/" + file.getOriginalFilename()));
}
}
but when i build jar and runs, it throws IOException saying,
java.nio.file.NoSuchFileException: images\8c9.jpeg.
So my question is how can i add the images folder inside the jar executable itself.
Thanks.

You should provide a full path for the images folder, or save in java.io.tmpdir creating the image folder first.
But, in my opinion you should configure your upload folder from a config file for flexibility. Take a look at this.
app:
profile-image:
upload-dir: C:\\projs\\web\\profile_image
file-types: jpg, JPG, png, PNG
width-height: 360, 360
max-size: 5242880
In your service or controller, do whatever you like, may be validate image type, size etc and process it as you like. For instance, if you want thumbnails(or avatar..).
In your controller or service class, get the directory:
#Value("${app.image-upload-dir:../images}")
private String imageUploadDir;
Finally,
public static Path uploadFileToPath(String fullFileName, String uploadDir, byte[] filecontent) throws IOException {
Path fileOut = null;
try{
Path fileAbsolutePath = Paths.get(StringUtils.join(uploadDir, File.separatorChar, fullFileName));
fileOut = Files.write(fileAbsolutePath, filecontent);
}catch (Exception e) {
throw e;
}
return fileOut; //full path of the file
}
For your question in the comment: You can use java.io.File.deleteOnExit() method, which deletes the file or directory defined by the abstract path name when the virtual machine terminates. TAKE A GOOD CARE THOUGH, it might leave some files if not handled properly.
try (ByteArrayOutputStream output = new ByteArrayOutputStream();){
URL fileUrl = new URL(url);
String tempDir = System.getProperty("java.io.tmpdir");
String path = tempDir + new Date().getTime() + ".jpg"; // note file extension
java.io.File file = new java.io.File(path);
file.deleteOnExit();
inputStream = fileUrl.openStream();
ByteStreams.copy(inputStream, output); // ByteStreams - Guava
outputStream = new FileOutputStream(file);
output.writeTo(outputStream);
outputStream.flush();
return file;
} catch (Exception e) {
throw e;
} finally {
try {
if(inputStream != null) {
inputStream.close();
}
if(outputStream != null) {
outputStream.close();
}
} catch(Exception e){
//skip
}
}

Delete file after Dropbox transfer fails

I try to use the official Dropbox API for uploading a zip file to my account. My project is a desktop application (standard Java). My code looks like this:
public void uploadZipFile(File file) throws Exception {
FileInputStream fis = new FileInputStream(file);
try {
getClient(accessToken).uploadFile("/" + file.getName(), DbxWriteMode.add(), file.length(), fis);
} finally {
fis.close();
}
}
private DbxClient getClient(String accessToken) {
DbxRequestConfig dbxRequestConfig = new DbxRequestConfig(Constants.APP_NAME, Locale.getDefault().toString());
return new DbxClient(dbxRequestConfig, accessToken);
}
And I call it:
File zipFile = new File("C:\\Test\\MyFile.zip");
try {
uploadZipFile(zipFile);
} catch (Exception e) {
e.printStackTrace();
}
The file is transferred without any problems but then I want to delete the file after synchronization:
File zipFile = new File("C:\\Test\\MyFile.zip");
try {
uploadZipFile(zipFile);
System.out.println(zipFile.delete());
} catch (Exception e) {
e.printStackTrace();
}
The file is transferred successfully again, but the file still exists in the local file system and the delete method returns false.

File not found exception even after bufferedwriter close

New edit:
Now i found the cause, it is because there are two servers and it write into temp folder in 1st server and try to read from the 2nd one. But I still didn't find a solution for this unless write to Amazon S3 and read from there.
I tried to export csv with struts2 action. However if I tried to export 10 times i can only succeed once, all the others failed with File not found exception (if I refresh the link again, the file can be downloaded). Here is my code:
public String exportFile(String fileName) {
File exportFile = null;
try {
if (CollectionUtils.isEmpty(receipts)) {
return "";
}
exportFile = File.createTempFile(fileName, ".csv");
exportFile.deleteOnExit();
try (BufferedWriter fw = new BufferedWriter(new FileWriter(exportFile))) {
try {
fw.write("test");
} finally {
fw.close();
}
}
return exportFile.getPath();
} catch (Exception ex) {
logger.error("Error exporting report. ", ex.getMessage());
}
return "";
}
String getStreamFromPath(String filePath) {
try {
File downloadFile = new File(filePath);
fileInputStream = new FileInputStream(downloadFile);
return SUCCESS;
} catch (IOException e) {
log.error(e.getMessage(), e);
return ERROR;
}
}
This is really weird, when i test in another server it works totally fine. Any ideas?

How to access /data folder of another application through your application?

there is a text file that an application produces, I would like to take that file and read it as strings in my application. How can I achieve that, any help would be grateful. Both applications are my applications so I can get the permissions.
Thank you!

This is possible using the standard android-storage, where all the user's files are stored too:
All you need to do is to access the same file and the same path in both applications, so e.g.:
String fileName = Environment.getExternalStorageDirectory().getPath() + "myFolderForBothApplications/myFileNameForBothApplications.txt";
Where myFolderForBothApplications and myFileNameForBothApplications can be replaced by your folder/filename, but this needs to be the same name in both applications.
Environment.getExternalStorageDirectory() returns a File-Object to the common, usable file-directory of the device, the same folder the user can see too.
By calling the getPath() method, a String representing the path to this storage is returned, so you can add your folder/filenames afterwards.
So a full code example would be:
String path = Environment.getExternalStorageDirectory().getPath() + "myFolderForBothApplications/";
String pathWithFile = path + "myFileNameForBothApplications.txt";
File dir = new File(path);
if(!dir.exists()) { //If the directory is not created yet
if(!dir.mkdirs()) { //try to create the directories to the given path, the method returns false if the directories could not be created
//Make some error-output here
return;
}
}
File file = new File(pathWithFile);
try {
f.createNewFile();
} catch (IOException e) {
e.printStackTrace();
//File couldn't be created
return;
}
Afterwards, you can write in the file or read from the file as provided e.g. in this answer.
Note that the file stored like this is visible for the user and my be edited / deleted by the user.
Also note what the JavaDoc for the getExternalStorageDirectory() says:
Return the primary external storage directory. This directory may not currently be accessible if it has been mounted by the user on their computer, has been removed from the device, or some other problem has happened. You can determine its current state with getExternalStorageState().
I do not know if this is the best/safest way to fix your problem, but it should work.

You can save the text file from your assets folder to anywhere in the sdcard, then you can read the file from the other application.
This method uses the getExternalFilesDir, that returns the absolute path to the directory on the primary shared/external storage device where the application can place persistent files it owns. These files are internal to the applications, and not typically visible to the user as media.
private void copyAssets() {
AssetManager assetManager = getAssets();
String[] files = null;
try {
files = assetManager.list("");
} catch (IOException e) {
Log.e("tag", "Failed to get asset file list.", e);
}
if (files != null) for (String filename : files) {
InputStream in = null;
OutputStream out = null;
try {
in = assetManager.open(filename);
File outFile = new File(Environment.getExternalStorageDirectory(), filename);
out = new FileOutputStream(outFile);
copyFile(in, out);
} catch(IOException e) {
Log.e("tag", "Failed to copy asset file: " + filename, e);
}
finally {
if (in != null) {
try {
in.close();
} catch (IOException e) {
// NOOP
}
}
if (out != null) {
try {
out.close();
} catch (IOException e) {
// NOOP
}
}
}
}
}
private void copyFile(InputStream in, OutputStream out) throws IOException {
byte[] buffer = new byte[1024];
int read;
while((read = in.read(buffer)) != -1){
out.write(buffer, 0, read);
}
}
And to read:
File dir = Environment.getExternalStorageDirectory();
File yourFile = new File(dir, "path/to/the/file/inside/the/sdcard.ext");

Missing bytes when calling HttpServletRequest.getInputSteam() method

I am creating Restful web service that accepts any file and saves it into filesystem. I am using Dropwizard to implement the service and Postman/RestClient to hit the request with data. I am not creating multipart (form-data) request.
Every thing is working fine except the file saved has first character missing. Here is my code for calling the service method and saving it into file system:
Input Request:
http://localhost:8080/test/request/Sample.txt
Sample.txt
Test Content
Rest Controller
#PUT
#Consumes(value = MediaType.WILDCARD)
#Path("/test/request/{fileName}")
public Response authenticateDevice(#PathParam("fileName") String fileName, #Context HttpServletRequest request) throws IOException {
.......
InputStream inputStream = request.getInputStream();
writeFile(inputStream, fileName);
......
}
private void writeFile(InputStream inputStream, String fileName) {
OutputStream os = null;
try {
File file = new File(this.directory);
file.mkdirs();
if (file.exists()) {
os = new FileOutputStream(this.directory + fileName);
logger.info("File Written Successfully.");
} else {
logger.info("Problem Creating directory. File can not be saved!");
}
byte[] buffer = new byte[inputStream.available()];
int n;
while ((n = inputStream.read(buffer)) != -1) {
os.write(buffer, 0, n);
}
} catch (Exception e) {
logger.error("Error in writing to File::" + e);
} finally {
try {
os.close();
inputStream.close();
} catch (IOException e) {
logger.error("Error in closing input/output stream::" + e);
}
}
}
In output, file is saved but first character from the content is missing.
Output:
Sample.txt:
est Content
In above output file, character T is missing and this happens for all the file formats.
I don't know what point I am missing here.
Please help me out on this.
Thank You.