How, when serializing, not to write an object to a specific file, but to create a new file in the selected directory always with a new name?

I am trying to serialize an object in java and subtract the given object from that file. But what I need is that I do not select a file for serialization, but that during serialization this file is created in the selected directory. That is, serialization creates a new file with an always new name

In the code, I apply the code for the selected file, but I can’t figure out how to always create a new file in the selected directory when serializing an object

public static void main(String args[]) throws IOException {
  FileOutputStream fos = new FileOutputStream("messages/FirstMessages.txt");
  ObjectOutputStream oos = new ObjectOutputStream(fos);
  TestSerial ts = new TestSerial();
  oos.writeObject(ts);
  oos.flush();
  oos.close();
}

And also how to understand that the proofreading will be from a new file. Maybe somehow through a variable?

I am attaching the code to read from the file.

 public static void main(String args[]) throws IOException {
  FileInputStream fis = new FileInputStream("messages/FirstMessages.txt");
  ObjectInputStream oin = new ObjectInputStream(fis);
  TestSerial ts = (TestSerial) oin.readObject();
  System.out.println("version="+ts.version);
}

Solution

Have you checked File.createTempFile()?

createTempFile

public static File createTempFile(String prefix, String suffix, File directory) throws IOException

Creates a new empty file in the specified directory, using the given prefix and suffix strings to generate its name. If this method returns successfully then it is guaranteed that:

The file denoted by the returned abstract pathname did not exist before this method was invoked, and

Neither this method nor any of its variants will return the same abstract pathname again in the current invocation of the virtual machine.

This method provides only part of a temporary-file facility. To arrange for a file created by this method to be deleted automatically, use the deleteOnExit() method.