some helpers for java.util.Date

DateHelp.java

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * some helpers for java.util.Date
 * @author keating_andy_given
 *
 */
public class DateHelp {
	
	public static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");

	/**
	 * 获取某日期后之后几天的日期
	 * @param someDate	某日期
	 * @param daysAfterSomeDate	天数
	 */
	public static Date dateAfterSomeDay(Date someDate, int daysAfterSomeDate){
		long time=(someDate.getTime()/1000)+60L*60*24*daysAfterSomeDate;
		Date newDate = new Date();
		newDate.setTime(time*1000);
		return newDate;
	}
	
	/**
	 * 日期明天,省略时间
	 */
	public static Date tomorrowWithoutTime(Date date) {
		return dateWithoutTime(dateAfterSomeDay(date, 1));
	}
	
	/**
	 * 获取一个与时间无关的日期,即时间为零点的日期
	 */
	public static Date dateWithoutTime(Date date) {
		try {
			return DateFormat.getDateInstance().parse(
					DateFormat.getDateInstance().format(date));
		} catch (ParseException e) {
			return null;
		}
	}

}