Java對日期Date類進行加減運算，年份加減，月份加減，時間差等等

在網上查閱資料，加上自己總結的一些關於Date類的工具類。

package com.data.utils;

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

public class DateFormat {

    /**
     * 日期減幾年
     */
    public static String dateMinusYear(String str) throws Exception {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMM");
        Date dt = sdf.parse(str);
        Calendar rightNow = Calendar.getInstance();
        rightNow.setTime(dt);
        rightNow.add(Calendar.YEAR, -1);// 日期減1年
        Date dt1 = rightNow.getTime();
        String reStr = sdf.format(dt1);
        return reStr;
    }

    /**
     * 日期加幾年
     */
    public static String dateAddYear(String str) throws Exception {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMM");
        Date dt = sdf.parse(str);
        Calendar rightNow = Calendar.getInstance();
        rightNow.setTime(dt);
        rightNow.add(Calendar.YEAR, 1);// 日期加1年
        Date dt1 = rightNow.getTime();
        String reStr = sdf.format(dt1);
        return reStr;
    }

    /**
     * 日期減幾月
     */
    public static String dateMinusMonth(String str) throws Exception {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMM");
        Date dt = sdf.parse(str);//將字符串生成Date
        Calendar rightNow = Calendar.getInstance();
        rightNow.setTime(dt);//使用給定的 Date 設置此 Calendar 的時間。 
        rightNow.add(Calendar.MONTH, -1);// 日期減1個月
        Date dt1 = rightNow.getTime();//返回一個表示此 Calendar 時間值的 Date 對象。
        String reStr = sdf.format(dt1);//將給定的 Date 格式化爲日期/時間字符串，並將結果添加到給定的 StringBuffer。
        return reStr;
    }

    /**
     * 日期加幾月
     */
    public static String dateAddMonth(String str) throws Exception {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMM");
        Date dt = sdf.parse(str);
        Calendar rightNow = Calendar.getInstance();
        rightNow.setTime(dt);
        rightNow.add(Calendar.MONTH, 1);// 日期加3個月
        // rightNow.add(Calendar.DAY_OF_YEAR,10);//日期加10天
        Date dt1 = rightNow.getTime();
        String reStr = sdf.format(dt1);
        return reStr;
    }

    /**
     * 獲取當前年月的第一個月的str
     * @param str
     *            201505
     * @return 201501
     * @throws Exception
     */
    public static String dateOneMonth(String str) {

        str = str.substring(0, str.length() - 2);
        str = str + "01";
        return str;
    }

    /**
     * 算出所選月份距離一月份有幾個月。
     * @param str 201509
     * @return 9
     */
    public static int dateDistanceMonth(String str) {

        int i = Integer.parseInt(str);
        int j = Integer.parseInt(DateFormat.dateOneMonth(str));
        System.out.println(i - j);
        return i - j + 1;
    }

    /**
     * 獲取兩個時間的時間差，精確到毫秒
     * @param str
     * @return
     */
    public static String TimeDifference(long start, long end) {

        long between = end - start;
        long day = between / (24 * 60 * 60 * 1000);
        long hour = (between / (60 * 60 * 1000) - day * 24);
        long min = ((between / (60 * 1000)) - day * 24 * 60 - hour * 60);
        long s = (between / 1000 - day * 24 * 60 * 60 - hour * 60 * 60 - min * 60);
        long ms = (between - day * 24 * 60 * 60 * 1000 - hour * 60 * 60 * 1000
                - min * 60 * 1000 - s * 1000);
        String timeDifference = day + "天" + hour + "小時" + min + "分" + s + "秒" + ms
                + "毫秒";
        return timeDifference;
    }
}

    /**
     * 獲取24小時、一週、一個月的起始時間
     * 
     * @param timeInterval
     *            : DAY_TIME_INTERVAL WEEK_TIME_INTERVAL MONTH_TIME_INTERVAL
     * @return "yyyy-mm-dd hh:mm:ss"
     */
    public static String getStartTime(int timeInterval) {
        Calendar cal = Calendar.getInstance();
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        if (DAY_TIME_INTERVAL == timeInterval) {// 獲取24小時的起始時間
            cal.set(Calendar.HOUR_OF_DAY, 0);
            cal.set(Calendar.MINUTE, 0);
            cal.set(Calendar.SECOND, 0);
            String startTime = sdf.format(cal.getTime());
            return startTime;
        } else if (WEEK_TIME_INTERVAL == timeInterval) {
            int weekday = cal.get(Calendar.DAY_OF_WEEK) - 1;
            cal.add(Calendar.DATE, -weekday);
            cal.set(Calendar.HOUR_OF_DAY, 0);
            cal.set(Calendar.MINUTE, 0);
            cal.set(Calendar.SECOND, 0);
            String startTime = sdf.format(cal.getTime());
            return startTime;
        } else if (MONTH_TIME_INTERVAL == timeInterval) {
            int dayofmonthMin = cal.getActualMinimum(Calendar.DAY_OF_MONTH);
            // c.add(Calendar.DATE, -dayofmonth);
            cal.set(Calendar.DATE, dayofmonthMin);
            cal.set(Calendar.HOUR_OF_DAY, 0);
            cal.set(Calendar.MINUTE, 0);
            cal.set(Calendar.SECOND, 0);
            String startTime = sdf.format(cal.getTime());
            return startTime;
        }
        return null;
    }

    /**
     * 獲取24小時、一週、一個月的結束時間
     * 
     * @param timeInterval
     *            : DAY_TIME_INTERVAL WEEK_TIME_INTERVAL MONTH_TIME_INTERVAL
     * @return "yyyy-mm-dd hh:mm:ss"
     */
    public static String getEndTime(int timeInterval) {
        Calendar cal = Calendar.getInstance();
        cal.setTimeZone(TimeZone.getTimeZone("GMT+8"));
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        if (DAY_TIME_INTERVAL == timeInterval) {
            cal.set(Calendar.HOUR_OF_DAY, 23);
            cal.set(12, 59);
            cal.set(13, 59);
            long date = cal.getTimeInMillis();
            String endTime = sdf.format(new Date(date));
            return endTime;
        } else if (WEEK_TIME_INTERVAL == timeInterval) {
            int weekday = cal.get(Calendar.DAY_OF_WEEK) - 1;
            cal.add(Calendar.DATE, -weekday);
            cal.add(Calendar.DATE, 6);
            cal.set(Calendar.HOUR_OF_DAY, 23);
            cal.set(12, 59);
            cal.set(13, 59);
            long date = cal.getTimeInMillis();
            String endTime = sdf.format(new Date(date));
            return endTime;
        } else if (MONTH_TIME_INTERVAL == timeInterval) {
            int dayOfMonthMax = cal.getActualMaximum(Calendar.DAY_OF_MONTH);
            cal.set(Calendar.DATE, dayOfMonthMax);
            cal.set(Calendar.HOUR_OF_DAY, 23);
            cal.set(Calendar.MINUTE, 59);
            cal.set(Calendar.SECOND, 59);
            String endTime = sdf.format(cal.getTime());
            return endTime;
        }
        return null;
    }
    /**
     * 判斷dateStr是否在start和end中間，start和end都可以爲null yyyyMMddHHmmss或者yyyyMMdd格式
     * 
     * @author you.xu
     * @date 2015年8月19日下午3:11:46
     * @param dateStr
     * @param start
     * @param end
     * @return
     */
    public static boolean checkDateVal(String dateStr, String start, String end) {
        boolean isDateRight = false;
        Date date = null;
        Date startDate = null;
        Date endDate = null;
        SimpleDateFormat sdf = null;
        // 判斷日期格式
        if (14 == dateStr.length()) {
            sdf = new SimpleDateFormat("yyyyMMddHHmmss");
        } else if (8 == dateStr.length()) {
            sdf = new SimpleDateFormat("yyyyMMdd");
        } else
            return false;

        try {
            // 更改判斷日期格式
            date = sdf.parse(dateStr);
        } catch (ParseException e) {
            log.error(e, e);
        }

        if ((start == null) && (end != null)) {
            try {
                endDate = sdf.parse(end);
            } catch (ParseException ex1) {
                log.error(ex1, ex1);
            }
            if ((date != null) && (endDate != null))// Check parameters for
            {
                if (date.compareTo(endDate) <= 0)
                    isDateRight = true;
            }
        } else if ((start != null) && (end == null)) {
            try {
                startDate = sdf.parse(start);
            } catch (ParseException ex1) {
                log.error(ex1, ex1);
            }
            if ((date != null) && (startDate != null)) {
                if (date.compareTo(startDate) >= 0)
                    isDateRight = true;
            }
        } else if ((start != null) && (end != null)) {
            try {
                startDate = sdf.parse(start);
                endDate = sdf.parse(end);
            } catch (ParseException ex2) {
                System.out.println(ex2.toString());
            }
            if ((startDate != null) && (date != null) && (endDate != null)) {
                if ((date.compareTo(startDate) >= 0)
                        && (date.compareTo(endDate) <= 0))
                    isDateRight = true;
            }
        }
        return isDateRight;
    }

    /**
     * 判斷dateStr是否在start和end中間，start和end都可以爲null long形格式
     * 
     * @author you.xu
     * @date 2015年8月19日下午3:12:35
     * @param dateStr
     * @param start
     * @param end
     * @return
     */
    public static boolean checkDateV(String dateStr, String start, String end) {
        boolean isDateRight = false;
        long date = -1;
        long fromDate = -1;
        long toDate = -1;

        date = java.lang.Long.parseLong(dateStr);

        if ((start == null) && (end == null)) {
            isDateRight = true;
        } else if ((start == null) && (end != null)) {
            try {
                toDate = java.lang.Long.parseLong(end);
            } catch (NumberFormatException nfe) {
                log.error(nfe, nfe);
            }
            if (date <= toDate) {
                isDateRight = true;
            }
        } else if ((start != null) && (end == null)) {
            try {
                fromDate = java.lang.Long.parseLong(start);
            } catch (NumberFormatException nfe) {
                log.error(nfe, nfe);
            }

            if (date >= fromDate) {
                isDateRight = true;
            }
        } else if ((start != null) && (end != null)) {
            try {
                toDate = java.lang.Long.parseLong(end);
                fromDate = java.lang.Long.parseLong(start);
            } catch (NumberFormatException nfe) {
                log.error(nfe, nfe);
            }

            if ((date <= toDate) && (date >= fromDate)) {
                isDateRight = true;
            }
        }
        return isDateRight;
    }

目前就用到了這些，隨時添加，有簡單方便的時間工具類，希望和大家一起學習，在評論中指出。thanks！！！