公历 "cal.add" 方法问题

Question

我目前正在尝试编写一个程序，其中 returns 从今天的当前日期算起 100 天。这是代码：

public class gregorianCalendar {
    public static void main(String[] args){
        Calendar cal = new GregorianCalendar();
        int year = cal.get(Calendar.YEAR);
        int month = cal.get(Calendar.MONTH);
        int dayOfMonth = cal.get(Calendar.DAY_OF_MONTH);
        int weekday = cal.get(Calendar.DAY_OF_WEEK);

        cal.add(Calendar.DAY_OF_MONTH, 100);
        System.out.print("100 days from today, the date will be: " + month);
        System.out.print("/" + dayOfMonth);
        System.out.println("/" + year);
    }
}

代码的输出给出当前日期，而不是当前日期后 100 天的日期。任何帮助将不胜感激。

Answer 1

public class gregorianCalendar {
    public static void main(String[] args){
        Calendar cal = new GregorianCalendar();
        cal.add(Calendar.DAY_OF_MONTH, 100); // <------- add should be here
        int year = cal.get(Calendar.YEAR);
        int month = cal.get(Calendar.MONTH);
        int dayOfMonth = cal.get(Calendar.DAY_OF_MONTH);
        int weekday = cal.get(Calendar.DAY_OF_WEEK);

        System.out.print("100 days from today, the date will be: " + month);
        System.out.print("/" + dayOfMonth);
        System.out.println("/" + year);
    }
}

或

public class gregorianCalendar {
    public static void main(String[] args){
        Calendar cal = new GregorianCalendar();
        // --------------- Current Date ------------
        int year = cal.get(Calendar.YEAR);
        int month = cal.get(Calendar.MONTH);
        int dayOfMonth = cal.get(Calendar.DAY_OF_MONTH);
        int weekday = cal.get(Calendar.DAY_OF_WEEK);
        System.out.print("today, the date is: " + month);
        System.out.print("/" + dayOfMonth);
        System.out.println("/" + year);    


        // ---------- Current date + 100------------
        cal.add(Calendar.DAY_OF_MONTH, 100);
        System.out.print("100 days from today, the date will be: " + cal.get(Calendar.MONTH));
        System.out.print("/" + cal.get(Calendar.DAY_OF_WEEK));
        System.out.println("/" + cal.get(Calendar.YEAR));
    }
}

公历 "cal.add" 方法问题

Gregorian Calendar "cal.add" Method Issues

java

gregorian-calendar