Question regarding property files

Question

I am new to java and I wrote a class that creates a property file.
But when i read it i also get a timestamp.

Where does this timestamp come from?

Here the code for reference

import java.io.*;
import java.util.*;

public class WritePropertiesFile {
public static void main(String[] args){
try{
Properties properties = new Properties();
properties.setProperty("username", "abcdef");
properties.setProperty("password", "012345");

File file = new File("c://........");

if(file.createNewFile()){
System.out.println("File is created!");
}
else{
System.out.println("File already exists");
}

FileOutputStream fileOut = new FileOutputStream(file);
properties.store(fileOut, "User");
fileOut.close();

}
catch(FileNotFoundException e){
e.printStackTrace();
}
catch(IOException e){
e.printStackTrace();
}
}
}

Output:

#User
#Thu Mar 09 14:06:25 CET 2017
password=012345
username=abcdef

Answer 1

By output you mean the content of the output file?

By the way, it seems clear that the Properties class have a method which uses the given OutputStream to write its data into it. That method contains the format of the file output generating, so in a nutshell, Properties does save itself into file this way. May you could check if there is a flag on the object like .setUseTimestamp(false) or there is an overload of thr method which accepts a boolean parameter for that. Anyways, Properties structure is like any config file, tags and values, this plus information does not influence the stored data, that's like a comment. Reason? Why not. Sometimes it can be useful to check who was the last modifier.