“\\ n”在使用PrintWriter将字符串保存到文本时不添加新行

Question

I want to print a string to a text using out.print but the \\n in the string are not working.

Here is the code:

import java.io.PrintWriter;

public class LetterRevisited{
    public static void main(String[] args)throws Exception
    {
        PrintWriter out = new PrintWriter("Test.txt");
        out.println("This is the first line\n" +
        "This is the second line" );
    out.close();
    }
}

But in the saved file no new line is created, all the lines are after each other. Any idea how to fix this? (beside adding out.println to all lines.)

Edit: I compile and run the code with windows command prompt and open the file with notepad.

Answer 1

Different platforms use different line separators.

• Windows use \\r\\n
• Unix-like platforms use \\n
• Mac now uses \\n too, but it used to use \\r .

(You can see more information and variants here )

You can get your "local" line separator by using

System.getProperty("line.separator")

eg

out.println("Hello" + System.getProperty("line.separator") + "World");

However, it is easier to use %n in a string formatter:

out.printf("Hello%nWorld%n");

If you are targeting a particular platform, you can just use the literal.

Answer 2

If you are using Java 7 then you can use System.lineSeparator()..see if this helps. For older versions of Java you can use - System.getProperty("line.separator")

Example : System.out.println(System.lineSeparator()+"This is the second line");