年和周

import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public class DateUtil {
	
	/*根据年份和星期的序号，获取该星期从哪一天到哪一天*/
	public static String getWeekGap(int year, int weekNum) {
		Calendar c = Calendar.getInstance();
		c.set(year, 0, 01); // 月份是从零开始
		int weekDay = c.get(Calendar.DAY_OF_WEEK) == 1 ? 8 : c
				.get(Calendar.DAY_OF_WEEK);
		c.add(Calendar.DATE, 7 * weekNum);

		c.add(Calendar.DATE, Calendar.MONDAY - weekDay);
		Date start = c.getTime();
		c.add(Calendar.DATE, 6);
		Date end = c.getTime();

		String datestr = String.format("%1$tY-%1$tm-%1$td", start) + "至"
				+ String.format("%1$tY-%1$tm-%1$td", end);
		return datestr;
	}
	/*获取当前星期从哪一天到哪一天*/
	public static String getWeekGap_Default() {
		Calendar c = Calendar.getInstance();
		c.getTime();
		int weekDay = c.get(Calendar.DAY_OF_WEEK) == 1 ? 8 : c
				.get(Calendar.DAY_OF_WEEK);
		c.add(Calendar.DATE, Calendar.MONDAY - weekDay);
		Date start = c.getTime();
		c.add(Calendar.DATE, 6);
		Date end = c.getTime();

		String datestr = String.format("%1$tY-%1$tm-%1$td", start) + "至"
				+ String.format("%1$tY-%1$tm-%1$td", end);
		return datestr;
	}
	/*获取当前星期是一年中第几个星期*/
	public static int getWeekNumOfYear(){
		TimeZone zone=TimeZone.getTimeZone("Asia/Shanghai");
		Calendar cal = Calendar.getInstance(zone);
		int c = cal.get(Calendar.WEEK_OF_YEAR);
		System.out.println(c);
		return c-1;
	}
	
	public static int getYear(){
		Calendar ca = Calendar.getInstance();
	    ca.setTime(new java.util.Date());
		return ca.get(Calendar.YEAR);
	}
	
}