java类库中的LocalDate类
package com.company;
import java.time.*;
//实现输出当前月份的日历,并且标出今天的日期和星期
public class study {
public static void main(String[] args) {
//构造对象,表示构造这个对象时的时间,
//从默认时区的系统时钟获取当前日期。
LocalDate date = LocalDate.now();
int year = date.getYear();
int month = date.getMonthValue();
int today = date.getDayOfMonth();
//LocalDate类的minusDays()方法
//基于当前获得的系统日期根据时间规则减1天
date = date.minusDays(today - 1);
//DayOfWeek类的getDayOfWeek()方法
/*javaAPI关于dayofweek
*https://blog.youkuaiyun.com/weixin_36470210/article/details/114186274
* */
//返回指定日期的英文星期字段
DayOfWeek weekday = date.getDayOfWeek();
int value = weekday.getValue();
System.out.println(year + "年," + month + "月份");
System.out.println(" 一 二 三 四 五 六 日");
for (int i = 1; i < value; i++)
System.out.print(" ");
while (date.getMonthValue() == month) {
System.out.printf("%3d", date.getDayOfMonth());
if (date.getDayOfMonth() == today)
System.out.print("*");
else
System.out.print(" ");
date = date.plusDays(1);
if (date.getDayOfWeek().getValue() == 1) System.out.println();
}
if (date.getDayOfWeek().getValue() != 1) System.out.println();
}
}