Java Data Type - 如何从字符串常量获取枚举值

enum Week {
  Monday, Tuesday, Wednesday, Thursday, Friday, Saturaday, Sunday
}

public class MainClass {
  public static void main(String args[]) {
    Week day;

    // 
    day = Week.valueOf("Monday");
    System.out.println("day contains " + day);
  }
}