java - 默认更改日历日期

Question

我在android项目中遇到了一个奇怪的问题。我正在尝试将日期转换为其他日期，为此，我正在计算两个日期之间的天数。所以，这就是我的实施方式。

Calendar baseEngDate = new GregorianCalendar();
Calendar currentEngDate= new GregorianCalendar();
baseEngDate.set(startingEngYearForSelection, startingEngMonthForSelection, startingEngDayForSelection);
currentEngDate.set(engYear, engMonth, engDay);
long totalEngDaysCount = daysBetween(baseEngDate, currentEngDate);

这是我的 baseEngDate 日历。set 方法有 3 个参数，它们具有以下参数，它们的默认值是：

int startingEngYearForSelection = 1944;
int startingEngMonthForSelection = 1;
int startingEngDayForSelection = 1;

但是，当我尝试在这个函数中检查它们的值时，

 private long daysBetween(Calendar startDate, Calendar endDate) {

        SimpleDateFormat myFormat = new SimpleDateFormat("dd MM yyyy");
        String inputString1 = null;
        String inputString2 = null;

        Date date1 = startDate.getTime();
        Date date2 = endDate.getTime();

        inputString1 = myFormat.format(date1);
        inputString2 = myFormat.format(date2);
        Log.e("String", inputString1); 
.
.
.

    }

我在日志中得到了这个值，这不是我所期望的：

2018-11-14 13:55:29.982 15712-15712/com.utilnepal E/String: 01 02 1944

它应该返回 01 01 1944 但它返回 01 02 1994。为什么？

Answer 1

应用它并以所需格式获取您的日期：

In Java Calender January is 0 and others so on increment 1  

startingEngMonthForSelection 将是 0 而不是 1；

 int startingEngYearForSelection = 1944;
 int startingEngMonthForSelection = 0;
 int startingEngDayForSelection = 1;

long diff = endDate.getTimeInMillis() - startDate.getTimeInMillis(); 

     SimpleDateFormat myFormat = new SimpleDateFormat("dd MM yyyy");
     Calendar calendar = Calendar.getInstance();
     calendar.setTimeInMillis(diff);
     String date=formatter.format(calendar.getTime());