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/** * 日期操作类 * 开发公司:北京东达悦科技有限公司 * 开发人:宋海鹏 * 最后更新日期:2013-09-10 */package com.imstudio.common;import java.text.ParseException;import java.text.SimpleDateFormat;import java.util.Date;public class DatetimeHelper {    private static String datePattern = "yyyy-MM-dd";    private static String timePattern = datePattern + " HH:mm:ss";    private static String minDate = "1900-01-01";    public static String getDatePattern() {        return datePattern;    }    public static String getTimePattern() {        return timePattern;    }    public static final String DatetimeToString(Date date, String pattern) {        SimpleDateFormat df = null;        String dateString = "";        if (date != null) {            df = new SimpleDateFormat(pattern);            dateString = df.format(date);        }        return dateString;    }    public static final String DateToString(Date date) {        return DatetimeToString(date, datePattern);    }    public static final String DatetimeToString(Date date) {        return DatetimeToString(date, timePattern);    }    public static final Date StringToDatetime(String date, String pattern) {        SimpleDateFormat df = null;        Date dateValue = null;        df = new SimpleDateFormat(pattern);        try {            dateValue = (Date) df.parse(date);        } catch (ParseException pre) {            return null;        }        return dateValue;    }    public static final Date StringToDate(String date) {        return StringToDatetime(date, datePattern);    }    public static final Date StringToDatetime(String date) {        return StringToDatetime(date, timePattern);    }    public static final String Now(String pattern) {        Date dt = new Date();        SimpleDateFormat df = new SimpleDateFormat(pattern);        return df.format(dt);    }    public static final String Now() {        return Now(timePattern);    }    public static final String Today() {        return Now(datePattern);    }    public static final String Today(String pattern) {        return Now(pattern);    }    public static final Date MinDate() {        return StringToDate(minDate);    }    public static final Long DateDiff(Date start, Date end) {        long days = 0;        days = (start.getTime() - end.getTime()) / (60 * 60 * 24 * 1000);        return days;    }    public static final Long DateDiff(String start, String end) {        return DateDiff(StringToDatetime(start), StringToDatetime(end));    }    public static final Long DateDiff(String end) {        return DateDiff(StringToDatetime(Today()), StringToDatetime(end));    }    @SuppressWarnings("deprecation")    public static final Long Age(Date today, Date birthday) {        long age = 0;        age = today.getYear() - birthday.getYear();        if (today.getMonth() == birthday.getMonth()) {            age = (today.getDay() < birthday.getDay()) ? age - 1 : age;        } else {            age = (today.getMonth() > birthday.getMonth()) ? age : age - 1;        }        return age;    }}