获取周数，周数开始日期、结束日期

package com.admin.util;

import java.text.SimpleDateFormat;import java.util.Calendar;import java.util.Date;import java.util.GregorianCalendar;

public class YwdTest { // 获取当前时间所在年的周数 public static int getWeekOfYear(Date date) { Calendar c = new GregorianCalendar(); c.setFirstDayOfWeek(Calendar.MONDAY); c.setMinimalDaysInFirstWeek(7); c.setTime(date);

return c.get(Calendar.WEEK_OF_YEAR); }

// 获取当前时间所在年的最大周数 public static int getMaxWeekNumOfYear(int year) { Calendar c = new GregorianCalendar(); c.set(year, Calendar.DECEMBER, 31, 23, 59, 59);

return getWeekOfYear(c.getTime()); }

// 获取某年的第几周的开始日期 public static Date getFirstDayOfWeek(int year, int week) { Calendar c = new GregorianCalendar(); c.set(Calendar.YEAR, year); c.set(Calendar.MONTH, Calendar.JANUARY); c.set(Calendar.DATE, 1);

Calendar cal = (GregorianCalendar) c.clone(); cal.add(Calendar.DATE, week * 7);

return getFirstDayOfWeek(cal.getTime()); }

// 获取某年的第几周的结束日期 public static Date getLastDayOfWeek(int year, int week) { Calendar c = new GregorianCalendar(); c.set(Calendar.YEAR, year); c.set(Calendar.MONTH, Calendar.JANUARY); c.set(Calendar.DATE, 1);

Calendar cal = (GregorianCalendar) c.clone(); cal.add(Calendar.DATE, week * 7);

return getLastDayOfWeek(cal.getTime()); }

// 获取当前时间所在周的开始日期 public static Date getFirstDayOfWeek(Date date) { Calendar c = new GregorianCalendar(); c.setFirstDayOfWeek(Calendar.MONDAY); c.setTime(date); c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek()); // Monday return c.getTime(); }

// 获取当前时间所在周的结束日期 public static Date getLastDayOfWeek(Date date) { Calendar c = new GregorianCalendar(); c.setFirstDayOfWeek(Calendar.MONDAY); c.setTime(date); c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek() + 6); // Sunday return c.getTime(); }

public static void main(String[] args) { int year = 2017; int week = 52;

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); Date today = new Date(); Calendar c = new GregorianCalendar(); c.setTime(today);

System.out.println("当前时间:current date = " + sdf.format(today)); System.out.println("当前第几周:getWeekOfYear = " + getWeekOfYear(today)); System.out.println("年度总周数:getMaxWeekNumOfYear = " + getMaxWeekNumOfYear(year)); System.out.println("本周第一天:getFirstDayOfWeek = " + sdf.format(getFirstDayOfWeek(year, week))); System.out.println("本周最后一天:getLastDayOfWeek = " + sdf.format(getLastDayOfWeek(year, week))); System.out.println("本周第一天:getFirstDayOfWeek = " + sdf.format(getFirstDayOfWeek(today))); System.out.println("本周最后一天:getLastDayOfWeek = " + sdf.format(getLastDayOfWeek(today))); }}

 

转载于:https://www.cnblogs.com/szh12345/p/8182411.html