小编use*_*915的帖子

public String getTypeOfDayWithSwitchStatement(int dayOfWeekArg) {
     String typeOfDay;
     switch (dayOfWeekArg) {
         case "Monday":
             typeOfDay = "Start of work week";
             break;
         case "Tuesday":
         case "Wednesday":
         case "Thursday":
             typeOfDay = "Midweek";
             break;
         case "Friday":
             typeOfDay = "End of work week";
             break;
         case "Saturday":
         case "Sunday":
             typeOfDay = "Weekend";
             break;
         default:
             throw new IllegalArgumentException("Invalid day of the week: " + dayOfWeekArg);
     }
     return typeOfDay;
}

注释以下行,抛出编译错误:

throw new IllegalArgumentException("Invalid day of the week: " + dayOfWeekArg);

也typeOfDay被视为未初始化的变量.

但为什么它之前不被视为未初始化的变量.