If we're told to use the system property line.separator instead of hard-coding \n, why does my code work on Windows?

Question

We all read something like this:

use the System.getProperty(String) method to refer to items which depend on the system, such as line terminators and path separators.

The quote is copied from this web site.

I hard-coded an \n, and the code below works on my Windows machine as expected.

package sample;

public class Main {

    public static void main(String[] args) {
        System.out.println("hello\nworld");
    };

}

The output is:

hello
world

I thought the Java compiler replaced \n with \r\n silently. So I downloaded JD GUI, opened the JAR file, and saw Hello\nworld. Can anybody give me an example where \n doesn't work and System.getProperty("line.separator") does?

Write your Sting into a file with the Java program, open it with Notepad and you will see what the Problem is — Jens, May 09 '17 at 08:41
@Jens, you're right. It looks like Command Prompt substitutes the correct line endings, and Notepad doesn't. So if you convert your comment to an answer, I'll accept it — Maksim Dmitriev, May 09 '17 at 08:55

score 0 · Answer 1 · edited May 23 '17 at 11:54

0

There are different line separators, depends on the OS. Read this thread: What is the difference between \r and \n?

Excerpt of if:

More importantly, Unix tends to use \n as a line separator; Windows tends to use \r\n as a line separator and Macs (up to OS 9) used to use \r as the line separator. (Mac OS X is Unix-y, so uses \n instead; there may be some compatibility situations where \r is used instead though.)

edited May 23 '17 at 11:54

Community

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answered May 09 '17 at 08:43

urgas9

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This is a possible duplicate question: http://stackoverflow.com/questions/36796136/difference-between-system-getpropertyline-separator-and-n – urgas9 May 09 '17 at 08:44

score 0 · Accepted Answer · answered Feb 28 '23 at 02:51

0

From the comment: It looks like Command Prompt substitutes the correct line endings, and Notepad doesn't.

answered Feb 28 '23 at 02:51

Maksim Dmitriev

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If we're told to use the system property line.separator instead of hard-coding \n, why does my code work on Windows?

2 Answers2