Vaadin 7: File Upload - vaadin7

Question

I have a Upload component in which I´m supposed to import a xml file in order to parse it.
I´m trying to use the File.createTempFile method to create the file phisically,but something weird is going on.
For example,if I take the file named "test.xml" and use the createTempFile method to create it on the disk,the name of the generate file becomes something like 'test.xml13234xml'.How can I create the file the correct way?

Answer 1

This is expected when using i.e. createTempFile method as it implicitly creates a file with random prefix:
// a part of createTempFile method
private static final SecureRandom random = new SecureRandom();
static File generateFile(String prefix, String suffix, File dir) {
long n = random.nextLong();
if (n == Long.MIN_VALUE) {
n = 0; // corner case
} else {
n = Math.abs(n);
}
return new File(dir, prefix + Long.toString(n) + suffix);
}
which should give something like 'test.xml13234xml'.
If you want to create a file with the correct name and keep it for later use you can rename/move it within uploadSucceeded method.
public class ExampleUpload implements Upload.Receiver, Upload.SucceededListener {
private Upload xmlUpload;
private File tempFile;
public ExampleUpload() {
this.xmlUpload = new Upload("Upload:", this);
this.xmlUpload.addSucceededListener(this);
}
#Override
public OutputStream receiveUpload(String filename, String mimeType) {
try {
tempFile = File.createTempFile(filename, "xml");
tempFile.deleteOnExit();
return new FileOutputStream(tempFile);
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
public void uploadSucceeded(SucceededEvent event) {
try {
File destinationFile = new File("c:\\" + event.getFilename());
FileUtils.moveFile(tempFile, destinationFile));
// TODO read and parse destinationFile
} catch (IOException e) {
e.printStackTrace();
}
}
}