Why can some ASCII characters not be expressed in the form '\uXXXX' in Java source code?

Question

I stumbled over this (again) today:

class Test {
    char ok = \'\\n\';
    char okAsWell = \'\\u000B\';
    char error = \'\\u000A\';
}

It

Answer 1

I think the reason is that \uXXXX sequences are expanded when the code is being parsed, see JLS §3.2. Lexical Translations.