我想知道约会的日子。当我在 cal.set(year,month-1,day) 中设置日期时,设置日历字段YEAR、MONTH、DAY_OF_MONTH、HOUR_OF_DAY 和 MINUTE 的值。其他字段的先前值将被保留。因此,当我执行 cal.DAY_OF_WEEK 时,我将获得已经存在的值。
但是 cal.get(cal.DAY_OF_WEEK) 如何给出正确的值呢? (如java文档中所述,public int get(int field)返回给定日历字段的值。)我不明白如何在此函数中传递整数值(作为日历)字段也未修改) 给出了正确的输出。
public static String findDay() {
Calendar cal = Calendar.getInstance();
cal.set(2019,1,15);
System.out.println(cal.toString());
System.out.println(cal.DAY_OF_WEEK); //7 which is unchanged by cal.set
System.out.println(cal.get(cal.DAY_OF_WEEK)); //6
return "";
}
代码输出:
java.util.GregorianCalendar[time=?,areFieldsSet=false,areAllFieldsSet=true,lenient=true,zone=sun.util.calendar.ZoneInfo[id="Etc/UTC",offset=0,dstSavings=0,useDaylight=false,transi
tions=0,lastRule=null],firstDayOfWeek=1,minimalDaysInFirstWeek=1,ERA=1,YEAR=2019,MONTH=1,WEEK_OF_YEAR=7,WEEK_OF_MONTH=3,DAY_OF_MONTH=15,DAY_OF_YEAR=46,DAY_OF_WEEK=6,DAY_OF_WEEK_IN
_MONTH=3,AM_PM=0,HOUR=11,HOUR_OF_DAY=11,MINUTE=38,SECOND=14,MILLISECOND=374,ZONE_OFFSET=0,DST_OFFSET=0]
7
6