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/**
 * All copyright reserved by NewHeight LTD.
 * 
 */
package com.yihaodian.gos.create.utils;

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

import org.apache.commons.lang.StringUtils;
import org.apache.log4j.Logger;

/**
 * DateTime 工具类
 * 
 * @version 0.1, 2012-7-24
 * @since   JDK1.6
 */
public class DateUtils
{
	
	private static final Logger log = Logger.getLogger(DateUtils.class);
	
	public static final int NEXT_DAY = 5; //added by bill 2010-07-20,@see #getNextDay,取代硬编码5天
	
	public static final String DEFAULT_DATE_FORMAT = "yyyy-MM-dd";
	
	public static final String PERIOD_DATE_FORMAT = "yyyyMMddHHmm";
	
	public static final String DO_DATE_FORMAT = "yyyyMMdd";

	
	/**
	 * 获取InvokeTimePeriod
	 * @return
	 */
	public static Long getInvokeTimePeriod(Date date){
		return Long.parseLong(new SimpleDateFormat(PERIOD_DATE_FORMAT).format(date));
	}

	/**
	 * 
	* @Title: subDays
	* @Description: 返回date1和date2之间相差的天数
	* @param date1
	* @param date2
	* @return int 返回类型
	 */
    public static int subDays(Date date1, Date date2){
        long d1 = DateUtils.toDate(DateUtils.getStringDate(date1), DEFAULT_DATE_FORMAT).getTime();
        long d2 = DateUtils.toDate(DateUtils.getStringDate(date2), DEFAULT_DATE_FORMAT).getTime();
        return (int) (d1 - d2) / (1000 * 60 * 60 * 24);

    }
    
    /**
     * 
    * @Title: getDateByDateString
    * @Description: 将dateString型的字符串转换为date类型对象
    * @param dateString
    * @return Date 返回类型
     */
    public static Date getDateByDateString(String dateString){
        SimpleDateFormat df = new SimpleDateFormat(DEFAULT_DATE_FORMAT);
        try {
        	return df.parse(dateString);
        } catch (ParseException e) {
            return new Date();
        }
    }

    /**
     * 
    * @Title: getDateByDateString
    * @Description: 将dateString型的字符串转换为date类型对象
    * @param dateString
    * @return Date 返回类型
     * @throws ParseException 
     */
    public static Date getDateByDateStr(String dateString) throws ParseException{
        SimpleDateFormat df = new SimpleDateFormat(DEFAULT_DATE_FORMAT);
        return df.parse(dateString);
    }
    
    /**
     * 
    * @Title: addDays
    * @Description: 返回指定日期(date)加上指定天数(days)后的日期
    * @param date
    * @param days
    * @return Date 返回类型
     */
    public static Date addDays(Date date, int days){
        Calendar cal = Calendar.getInstance();

        try {
            cal.setTime(date);
            cal.add(Calendar.DATE, days);

        } catch (Exception e) {
        	log.error("addDays error" , e);
        }
        return cal.getTime();

    }
    
    /**
     * @Title: addHour
     * @author guoyang
     * @Description: 返回指定日期(date)加上指定小时数(hours)后的日期
     * @param date
     * @param hour
     * @return
     */
    public static Date addHour(Date date, int hours){
        Calendar cal = Calendar.getInstance();

        try {
            cal.setTime(date);
            cal.add(Calendar.HOUR, hours);

        } catch (Exception e) {
        	log.error(e.getMessage(), e);
        }
        return cal.getTime();

    }
    
    /**
     * 
    * @Title: getStringDate
    * @Description: 以“yyyy-MM-dd”形式返回当前的年、月、日
    * @param d
    * @return String 返回类型
     */
    public static String getStringDate(Date d){
        Date date = d;
        SimpleDateFormat df = new SimpleDateFormat(DEFAULT_DATE_FORMAT);
        return df.format(date);
    }
    
    /**
     * @Title: getDoStringDate
     * @param  d 日期时间对象
     * @return 格式化的时间日期字符串
     */
    public static String getDoStringDate(Date d) {
        SimpleDateFormat simpledateformat = new SimpleDateFormat(DO_DATE_FORMAT);   
        return simpledateformat.format(d);   
    }
    
    /**
     * 
    * @Title: getStringDate
    * @Description: 以“yyyy-MM-dd HH:mm:ss”形式返回当前的年、月、日
    * @param d
    * @return String 返回类型
     */
    public static String getStringDateTime(Date d){
        Date date = d;
        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        return df.format(date);
    }
    
    /**
     * 
    * @Title: toDate
    * @Description: 将dateStr型的字符串转换为format格式的date类型对象
    * @param dateStr
    * @param format
    * @return Date 返回类型
     */
    public static Date toDate(String dateStr, String format){
        SimpleDateFormat df = new SimpleDateFormat(format);
        try {
            return df.parse(dateStr);
        } catch (ParseException e) {
            return new Date();
        }
    }
    
    /**
     * 
     * @Title: getFromatStringDateTime
     * @description 将String类型的时间转化为format格式的日期字符串
     * @param dateStr
     * @param format
     * @return String 转化后的时间
     */
    public static String getFromatStringDateTime(String dateStr, String format) {
		Date date = toDate(dateStr, format);
		return getStringDate(date);
	}

    /**
     * 
    * @Title: getStringTime
    * @Description: 以"HH:mm:ss"形式返回传入的时间
    * @param d
    * @return String 返回类型
     */
    public static String getStringTime(Date d){
        Date date = d;
        SimpleDateFormat df = new SimpleDateFormat("HH:mm:ss");
        return df.format(date);
    }
    
    /**
     * 
    * @Title: getNextDay
    * @Description: 得到日期后几天的日期时间
    * @param date
    * @return Date 返回类型
     */
    public static Date getNextDay(Date date){
    	if(date == null) {
    		date = new Date();
    	}
    	Calendar cal = Calendar.getInstance();
    	cal.setTime(date);
    	cal.add(Calendar.DATE,NEXT_DAY);
    	return cal.getTime();
    }
    
    /**
     * 设定比较日期的Calendar 时分秒
     * @param calendar
     * @param compareDateStr yyyy-MM-dd字符格式
     * @return Calendar 比较日期 （完整的年月日、时分秒）
     */
    public static Calendar getCompareCalendar(Calendar calendar,String compareDateStr){
    	if(StringUtils.isEmpty(compareDateStr) || calendar ==null){
			return null;
		}
		try{
			Calendar c = Calendar.getInstance();
			SimpleDateFormat sdf =  new SimpleDateFormat("yyyy-MM-dd");
			c.setTime(sdf.parse(compareDateStr));
			c.set(Calendar.HOUR_OF_DAY, calendar.get(Calendar.HOUR_OF_DAY));
			c.set(Calendar.MINUTE, calendar.get(Calendar.MINUTE));
			c.set(Calendar.SECOND, calendar.get(Calendar.SECOND));
			return c;
		}catch(Exception e){
			log.error(e);
			return null;
		}
    }
    
    /**
     * 取当前日期 
     * @return
     */
    public static Date getNowDate(){
    	String nowStr = getStringDate(new Date());
    	return getDateByDateString(nowStr);
    }
    
	public static String getDate8Str(Date date) {
		SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
		return format.format(date);
	}
	
	public static String getDate8Str() {
		SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
		return format.format(new Date());
	}

	public static Calendar getCalendar(Date date) {
		Calendar c = Calendar.getInstance();
		c.setTime(date);
		return c;
	}
	
	public static Date add(Date date, int field, int diff) {
		Calendar c = getCalendar(date);
		c.add(field, diff);
		return c.getTime();
	}
	
	/**
	 * 得到与当前时间相差 diff 天的时间
	 */
	public static Date nextDays(Date date, int diff) {
		return add(date, Calendar.DATE, diff);
	}
	
	/**
	 * 计算 d1 - d2 的毫秒差
	 */
	public static long diffMillis(Date d1, Date d2) {
		return d1.getTime() - d2.getTime();
	}
	
}