Normalization of platform specific line terminator characters

Line terminator character is platform specific. 

You can find the line termination character for your platform using System.lineSeparator()API call

On my windows machine, I get "\r\n" as the line termination character. 

jshell> System.lineSeparator()
$1 ==> "\r\n"

Unix & Linux uses "\n" as line termination character & some older versions of Mac OS uses "\r" as line termination character.

This poses a few issues with handling multi-line string literals represented by text blocks

• Some editor used may automatically change the line termination character
• When the source file gets edited on different platforms, there is a chance of getting different line termination characters getting used within the same text block. 

To avoid these issues, Java compiler normalizes line termination character inside the multi-line string literal in text blocks to '\n' while processing. So, all the different line termination characters "\r", "\r\n" and "\n" becomes "\n" after processing a text block.

Let us check this with the below program:

Code is shown as an image to make the line termination characters visible. Here the line termination character is "\r\n" represented by CR|LF

This produces the following output

Comparing with \n:true
Comparing with \r\n:false

indicating that \r\n line termination character in the source code is converted to \n after the text block is processed.

Below is the version of the code for copy/pasting if needed. 

public class Main {

    public static void main(String[] args) {

        String poemTextBlock = """
                 And miles to go before I sleep.
                 """;
 
        System.out.println("Comparing with \\n:" + "And miles to go before I sleep.\n".equals(poemTextBlock));
        System.out.println("Comparing with \\r\\n:" + "And miles to go before I sleep.\r\n".equals(poemTextBlock));
    }
}

In the next post, we will see if and how of using escape sequences within text blocks

Sample code used in this post can be downloaded from https://github.com/ashokkumarta/awesomely-java/tree/main/2021/03/Language-Features/Text-blocks/Normalization-of-platform-specific-line-terminator-characters