在java控制台打印日历

public static void main(String[] args) {

Locale.setDefault(Locale.ENGLISH);
GregorianCalendar d = new GregorianCalendar();
//现在是当前月份的第几天
int today = d.get(Calendar.DAY_OF_MONTH);
//现在是几月份
int month = d.get(Calendar.MONTH);
//设置当前时间为这个月的第一天
d.set(Calendar.DAY_OF_MONTH, 1);
//月份第一天是星期几
int weekday = d.get(Calendar.DAY_OF_WEEK);
//获取一星期的第一天
int firstDayOfWeek = d.getFirstDayOfWeek();
int indent = 0;
//如果月份的第一个天不是一个星期的第一天，要知道空几个空格，并把当前时间设置到一星期的第一天
while (weekday != firstDayOfWeek) {
indent++;
d.add(Calendar.DAY_OF_MONTH, -1);
weekday = d.get(Calendar.DAY_OF_WEEK);
}

//打印星期头
String[] weekdayNames = new DateFormatSymbols().getShortWeekdays();
do {
System.out.printf("%4s", weekdayNames[weekday]);
d.add(Calendar.DAY_OF_MONTH, 1);
weekday = d.get(Calendar.DAY_OF_WEEK);
}
while (weekday != firstDayOfWeek);
System.out.println();
for (int i = 1; i <= indent; i++) {
System.out.print("    ");
}
//设置当前时间为月初
d.set(Calendar.DAY_OF_MONTH, 1);
do {
//打印天数
int day = d.get(Calendar.DAY_OF_MONTH);
System.out.printf("%3d", day);

//标准当前日期
if (day == today) {
System.out.print("*");
} else {
System.out.print(" ");
}
d.add(Calendar.DAY_OF_MONTH, 1);
weekday = d.get(Calendar.DAY_OF_WEEK);

//到日期第一天，换行
if (weekday == firstDayOfWeek){
System.out.println();
}
}
while (d.get(Calendar.MONTH) == month);
//最后是否需要换行
if (weekday != firstDayOfWeek){
System.out.println();
}
}