package com.xjzd.common.util;
/**
* @ClassNameDateUtils
* @Description
* @Author liu pei
* @Date2020/9/15 13:45
* @Version V1.0
**/
public class DateUtils {
/**
* 获取指定年月的第一天
* @param year
* @param month
* @return
*/
public static String getFirstDayOfMonth1(int year, int month) {
Calendar cal = Calendar.getInstance();
//设置年份
cal.set(Calendar.YEAR, year);
//设置月份
cal.set(Calendar.MONTH, month-1);
//获取某月最小天数
int firstDay = cal.getMinimum(Calendar.DATE);
//设置日历中月份的最小天数
cal.set(Calendar.DAY_OF_MONTH,firstDay);
//格式化日期
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
return sdf.format(cal.getTime());
}
/**
* 获取指定年月的最后一天
* @param year
* @param month
* @return
*/
public static String getLastDayOfMonth1(int year, int month) {
Calendar cal = Calendar.getInstance();
//设置年份
cal.set(Calendar.YEAR, year);
//设置月份
cal.set(Calendar.MONTH, month-1);
//获取某月最大天数
int lastDay = cal.getActualMaximum(Calendar.DATE);
//设置日历中月份的最大天数
cal.set(Calendar.DAY_OF_MONTH, lastDay);
//格式化日期
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
return sdf.format(cal.getTime());
}
/**
* 获取当前月第一天
* @param month
* @return
*/
public static String getFirstDayOfMonth(int month) {
Calendar calendar = Calendar.getInstance();
// 设置月份
calendar.set(Calendar.MONTH, month - 1);
// 获取某月最小天数
int firstDay = calendar.getActualMinimum(Calendar.DAY_OF_MONTH);
// 设置日历中月份的最小天数
calendar.set(Calendar.DAY_OF_MONTH, firstDay);
// 格式化日期
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String firstDay = sdf.format(calendar.getTime())+" 00:00:00";
return firstDay;
}
public static String getLastDayOfMonth(int month) {
Calendar calendar = Calendar.getInstance();
// 设置月份
calendar.set(Calendar.MONTH, month - 1);
// 获取某月最大天数
int lastDay=0;
//2月的平年瑞年天数
if(month==2) {
lastDay = calendar.getLeastMaximum(Calendar.DAY_OF_MONTH);
}else {
lastDay = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
}
// 设置日历中月份的最大天数
calendar.set(Calendar.DAY_OF_MONTH, lastDay);
// 格式化日期
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String lastDay = sdf.format(calendar.getTime())+" 23:59:59";
return lastDay;
}
}
