Unicode to string conversion in Java

Question

I am building a language, a toy language. The syntax \#0061 is supposed to convert the given Unicode to an character:

String temp = yytext().subtring(2);

Then after that try to append '\u' to the string, I noticed that generated an error.

I also tried to "\\" + "u" + temp; this way does not do any conversion.

I am basically trying to convert Unicode to a character by supplying only '0061' to a method, help.

Answer 1

Strip the '#' and use Integer.parseInt("0061", 16) to convert the hex digits to an int. Then cast to a char.

(If you had implemented the lexer by hand, an alternatively would be to do the conversion on the fly as your lexer matches the unicode literal. But on rereading the question, I see that you are using a lexer generator ... good move!)

Answer 2

i am basically trying to convert unicode to a character by supplying only '0061' to a method, help.

char fromUnicode(String codePoint) {
  return (char)  Integer.parseInt(codePoint, 16);
}

You need to handle bad inputs and such, but that will work otherwise.