private static char unicodeToLowerCase(final char c){
  if (c < 128)   return c >= 'A' && c <= 'Z' ? (char)(c + 32) : c;
  return Character.toLowerCase(Character.toUpperCase(c));
}

private static char unicodeToLowerCase ( final char c ) { if ( c < 128 ) return c >= 'A' && c <= 'Z' ? ( char ) ( c + 32 ) : c ; return Character . toLowerCase ( Character . toUpperCase ( c ) ) ; }
a method to downcase correctly unicode characters optimised for ascii letters .
