How to convert any kind of white space to a char?

I use String.strip() (Java 11) to remove trailing & leading white spaces from a String. There are 25 different kinds of white spaces in a String. I want to test my code with some of these 25 types of white space.

I have a code example which converts a particular type of white space (ex. \u2002) into a char and then uses it in a String. When I try to convert another white space type like \u000A to char, I get a compiler error. Why does this happen and how to fix it ?

public static void main(String...args){
    char chr = '\u2002';//No problem.

    //Compiler error : 
    //Intellij IDEA compiler - Illegal escape character in character literal.
    //Java compiler - java: illegal line end in character literal.
    chr = '\u000a';

    String text = chr + "hello world" + chr;
    text = text.strip();
    System.out.println(text);
}

Are you sure you're not seeing this error instead?

> error: illegal line end in character literal

Escape sequences like \u000a are processed very early in the compilation process. The \u000a is being replaced with an actual line feed character (code point 10).

It's as if you wrote this:

    chr = '
';

which is why, when I try and compile your code using JDK 11.0.8, I get the "illegal line end" error.

This early conversion is described in the Java Language Specification:

> Because Unicode escapes are processed very early, it is not correct to write '\u000a' for a character literal whose value is linefeed (LF); the Unicode escape \u000a is transformed into an actual linefeed in translation step 1 (§3.3) and the linefeed becomes a LineTerminator in step 2 (§3.4), and so the character literal is not valid in step 3. Instead, one should use the escape sequence '\n' (§3.10.6). Similarly, it is not correct to write '\u000d' for a character literal whose value is carriage return (CR). Instead, use '\r'.