Java Utililty Methods Temp File Create

File createTempFile(@Nonnull String prefix, @Nonnull String suffix, @Nullable File parentDir)
Creates a temporary file

Random rand = new Random();
String parent = parentDir == null ? System.getProperty("java.io.tmpdir") : parentDir.getPath();
DecimalFormat fmt = new DecimalFormat("#####");
File result;
do {
 result = new File(parent, prefix + fmt.format(Math.abs(rand.nextInt())) + suffix);
} while (result.exists());
return result;
...

File createTempFile(final String file, final String ext)
create Temp File

File f = new File(file);
String filename = f.getName();
if (filename == null) {
 filename = "export";
SimpleDateFormat formatter = new SimpleDateFormat("yyyyMMddhhmm");
String date = formatter.format(new Date());
filename = filename + "_" + date + "_";
...

File createTempFile(String oriFileName)
create Temp File

return new File(System.getProperty("java.io.tmpdir"),
 new SimpleDateFormat("yyyyMMddHHmmssSSS").format(new Date()) + "_" + new Random().nextInt(99999)
 + "_" + oriFileName);

File getTempFile()
get Temp File

File f = File.createTempFile("tmp", ".html", null);
tempFiles.add(f);
return f;

File getTempFile()
get Temp File

return File.createTempFile("temp", Long.toString(System.nanoTime()));

File getTempFile(File file)
create a empty temp file at file's directory, temp file's name is based on file's name, i.e.

File tempFile;
while (true) {
 tempFile = new File(file.getParent(), file.getName() + ".tmp." + FILENAME_RANDOM.nextInt());
 if (!tempFile.exists()) {
 if (!tempFile.createNewFile()) {
 throw new IOException(String.format("create %s failed", tempFile));
 return tempFile;
...

File getTempFile(File parent, String fileName)
Getting a temp file object in the directory in temporal directory which is referrenced by System.getProperty("java.io.tmpdir") .

return new File(new File(getTempDirectory(), parent.getPath()), fileName);

File getTempFile(final File stackFile)
get Temp File

return new File("/tmp/" + stackFile.getName() + ".tmp");

File getTempFile(final String directory, final String suffix, boolean autodelete)
Creates a temporary file in the given directory, with the given suffix.

int num = randomNumberGenerator.nextInt(Integer.MAX_VALUE);
File file = new File(directory + File.separator + String.format("%06d.%s", num, suffix));
while (file.exists()) {
 num = randomNumberGenerator.nextInt(Integer.MAX_VALUE);
 file = new File(directory + File.separator + String.format("%06d.%s", num, suffix));
if (!file.createNewFile()) {
 throw new IOException("Failed to create file " + file.getAbsolutePath());
...

File getTempFile(final String name)
get Temp File

return new File("temp" + File.separator + "test", name).getCanonicalFile();