java获取本月第一天和最后一天

public class CalendarTest {
public static void main(String[] args) {
// 获取当前年份、月份、日期
Calendar cale = null;
cale = Calendar.getInstance();
int year = cale.get(Calendar.YEAR);
int month = cale.get(Calendar.MONTH) + 1;
int day = cale.get(Calendar.DATE);
int hour = cale.get(Calendar.HOUR_OF_DAY);
int minute = cale.get(Calendar.MINUTE);
int second = cale.get(Calendar.SECOND);
int dow = cale.get(Calendar.DAY_OF_WEEK);
int dom = cale.get(Calendar.DAY_OF_MONTH);
int doy = cale.get(Calendar.DAY_OF_YEAR);

System.out.println("Current Date: " + cale.getTime());
System.out.println("Year: " + year);
System.out.println("Month: " + month);
System.out.println("Day: " + day);
System.out.println("Hour: " + hour);
System.out.println("Minute: " + minute);
System.out.println("Second: " + second);
System.out.println("Day of Week: " + dow);
System.out.println("Day of Month: " + dom);
System.out.println("Day of Year: " + doy);

// 获取当月第一天和最后一天
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
String firstday, lastday;
// 获取前月的第一天
cale = Calendar.getInstance();
cale.add(Calendar.MONTH, 0);
cale.set(Calendar.DAY_OF_MONTH, 1);
firstday = format.format(cale.getTime());
// 获取前月的最后一天
cale = Calendar.getInstance();
cale.add(Calendar.MONTH, 1);
cale.set(Calendar.DAY_OF_MONTH, 0);
lastday = format.format(cale.getTime());
System.out.println("本月第一天和最后一天分别是 ： " + firstday + " and " + lastday);

// 获取当前日期字符串
Date d = new Date();
System.out.println("当前日期字符串1：" + format.format(d));
System.out.println("当前日期字符串2：" + year + "/" + month + "/" + day + " "
+ hour + ":" + minute + ":" + second);
}

}

运行效果图如下：