[Java] 문자열->정수 형변환

String -> Int

String from = "123";
int to = Integer.parseInt(from);
int to2 = Integer.valueOf(from)

Int -> String

int from = 123;
String to = Integer.toString(from);

Char -> Int

char from = '9';
int to = from - '0';

Int -> Char

int from = 9;
char to = (char)(from + '0');