Homework 11/16/2007: lab class definition 2

Study Display 4.4 (2nd ed. and 3rd ed.) or Display 4.2 & Display 4.3 (1st ed.) and then
1. Comment out date.setDate(6, 17, year); by // date.setDate(6, 17, year);
2. At the next line below, add date.readInput();
3. Run the program again. Fix any problems you may encouter along the way.
4. At the last line of your program, add System.out.println(date.month);
and see what happens. Why?

根據Display 4.4原始的程式碼:


















下圖紅色框起來的地方為關鍵點!!



































------------------------------------更改後----------------------------

加入 System.out.println(date.month);

我們可以發現到程式出現錯誤。因為在之前的程式碼(紅框的地方) month 被定義為private，所以date.month無法被叫出來。


















如果把 month 改為 public 則程式就可以執行。(如下圖)