how to upload a file - upload

Question

i try to upload a file from client to server
on the client side, i have a file input
on server side i have
private void uploadFile(final FileTransfer fileTransfer) {
String destinationFile = "/home/nat/test.xls";
InputStream fis = null;
FileOutputStream out = null;
byte buf[] = new byte[1024];
int len;
try {
fis = fileTransfer.getInputStream();
out = new FileOutputStream(new File(destinationFile));
while ((len = fis.read(buf)) > 0) {
out.write(buf, 0, len);
}
}
}
a file is created on the server, but it's empty
when i debug, i can see then fis is not null
any idea?

Answer 1

Here is a code extract of mine:
try {
File fileData = new File(fileTransfer.getFilename());
// Write the content (data) in the file
// Apache Commons IO: (FileUtils)
FileOutputStream fos = FileUtils.openOutputStream(fileData);
// Spring Utils: FileCopyUtils
FileCopyUtils.copy(fileTransfer.getInputStream(), fos);
// Alternative with Apache Commons IO
// FileUtils.copyInputStreamToFile(fileTransfer.getInputStream(), fileData);
// Send the file to a back-end service
myService.persistFile( fileData );
} catch (IOException ioex) {
log.error("Error with io")
}
return fileTransfer.getFilename(); // this is for my javascript callback fn
Apache Commons IO is a good library to use for such manipulations (I use Spring Utils as well). If you do not have a Spring context, use the commented alternative with Apache (check the syntax, it is not verified).