import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.GregorianCalendar; public class Test { // 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 = 2015; int week = 27; 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))); } } //输出结果: // 当前时间:current date = 2015-07-07 16:35:07 // 当前第几周:getWeekOfYear = 27 // 年度总周数:getMaxWeekNumOfYear = 52 // getFirstDayOfWeek = 2015-07-06 16:35:07 // getLastDayOfWeek = 2015-07-12 16:35:07 // getFirstDayOfWeek = 2015-07-06 16:35:07 // getLastDayOfWeek = 2015-07-12 16:35:07