Java Text Block

public class Test {
    public static void main(String[] args) {
        String message = """
                Hello world!
                    This line is started with indention     
                Reserved LE spaces    \s
                """;
        System.out.println(message.replaceAll("\s", "~"));
    }
}

Output:

Hello~world!
~~~~This~line~is~started~with~indention
Reserved~LE~spaces~~~~~