Java 获取指定日期的方法汇总

import java.text.DateFormat;
import java.text.ParsePosition;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

import org.junit.Test;

public class TimeUtil {
    // 用来全局控制 上一周，本周，下一周的周数变化
    private int weeks = 0;
    // 一月最大天数
    private int MaxDate;
    // 一年最大天数
    private int MaxYear;/**
     * 得到指定月后（前）的日期 参数传负数即可
     * 
     */
    public static String getAfterMonth(int month) {
        Calendar c = Calendar.getInstance();// 获得一个日历的实例
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Date date = null;
        try {
            date = sdf.parse("2009-11-04");// 初始日期
        } catch (Exception e) {

        }
        c.setTime(date);// 设置日历时间
        c.add(Calendar.MONTH, month);// 在日历的月份上增加6个月
        String strDate = sdf.format(c.getTime());// 的到你想要得6个月后的日期
        return strDate;

    }

    /**
     * 得到二个日期间的间隔天数
     */
    public static String getTwoDay(String sj1, String sj2) {
        SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
        long day = 0;
        try {
            java.util.Date date = myFormatter.parse(sj1);
            java.util.Date mydate = myFormatter.parse(sj2);
            day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);
        } catch (Exception e) {
            return "";
        }
        return day + "";
    }

    /**
     * 根据一个日期，返回是星期几的字符串
     */
    public static String getWeek(String sdate) {
        // 再转换为时间
        Date date = TimeUtil.strToDate(sdate);
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        // int hour=c.get(Calendar.DAY_OF_WEEK);
        // hour 中存的就是星期几了，其范围 1~7
        // 1=星期日 7=星期六，其他类推
        return new SimpleDateFormat("EEEE").format(c.getTime());
    }

    /**
     * 将短时间格式字符串转换为时间 yyyy-MM-dd
     */
    public static Date strToDate(String strDate) {
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
        ParsePosition pos = new ParsePosition(0);
        Date strtodate = formatter.parse(strDate, pos);
        return strtodate;
    }

    /**
     * 两个时间之间的天数
     *
     * @param date1
     * @param date2
     * @return
     */
    public static long getDays(String date1, String date2) {
        if (date1 == null || date1.equals(""))
            return 0;
        if (date2 == null || date2.equals(""))
            return 0;
        // 转换为标准时间
        SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
        java.util.Date date = null;
        java.util.Date mydate = null;
        try {
            date = myFormatter.parse(date1);
            mydate = myFormatter.parse(date2);
        } catch (Exception e) {
        }
        long day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);
        return day;
    }

    /**
     * 计算当月最后一天,返回字符串
     */
    public String getDefaultDay() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar lastDate = Calendar.getInstance();
        lastDate.set(Calendar.DATE, 1);// 设为当前月的1 号
        lastDate.add(Calendar.MONTH, 1);// 加一个月，变为下月的1 号
        lastDate.add(Calendar.DATE, -1);// 减去一天，变为当月最后一天
        str = sdf.format(lastDate.getTime());
        return str;
    }

    /**
     * 上月第一天
     */
    public String getPreviousMonthFirst() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar lastDate = Calendar.getInstance();
        lastDate.set(Calendar.DATE, 1);// 设为当前月的1 号
        lastDate.add(Calendar.MONTH, -1);// 减一个月，变为下月的1 号
        // lastDate.add(Calendar.DATE,-1);//减去一天，变为当月最后一天
        str = sdf.format(lastDate.getTime());
        return str;
    }

    /**
     * 获取当月第一天
     */
    public String getFirstDayOfMonth() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar lastDate = Calendar.getInstance();
        lastDate.set(Calendar.DATE, 1);// 设为当前月的1 号
        str = sdf.format(lastDate.getTime());
        return str;
    }

    /**
     * 获得本周星期日的日期
     */
    public String getCurrentWeekday() {
        weeks = 0;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 6);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    /**
     * 获取当天时间
     */
    public String getNowTime(String dateformat) {
        Date now = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat(dateformat);// 可以方便地修改日期格式
        String hehe = dateFormat.format(now);
        return hehe;
    }

    /**
     * 获得当前日期与本周日相差的天数
     */
    private int getMondayPlus() {
        Calendar cd = Calendar.getInstance();
        // 获得今天是一周的第几天，星期日是第一天，星期二是第二天......
        int dayOfWeek = cd.get(Calendar.DAY_OF_WEEK) - 1; // 因为按中国礼拜一作为第一天所以这里减1
        if (dayOfWeek == 1) {
            return 0;
        } else {
            return 1 - dayOfWeek;
        }
    }

    /**
     * 获得本周一的日期
     */
    public String getMondayOFWeek() {
        weeks = 0;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    /**
     * 获得相应周的周六的日期
     */
    public String getSaturday() {
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 * weeks + 6);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    /**
     * 获得上周星期日的日期
     */
    public String getPreviousWeekSunday() {
        weeks = 0;
        weeks--;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + weeks);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    /**
     * 获得上周星期一的日期
     */
    public String getPreviousWeekday() {
        weeks--;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 * weeks);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    /**
     * 获得下周星期一的日期
     */
    public String getNextMonday() {
        weeks++;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    /**
     * 获得下周星期日的日期
     */
    public String getNextSunday() {
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 + 6);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    private int getMonthPlus() {
        Calendar cd = Calendar.getInstance();
        int monthOfNumber = cd.get(Calendar.DAY_OF_MONTH);
        cd.set(Calendar.DATE, 1);// 把日期设置为当月第一天
        cd.roll(Calendar.DATE, -1);// 日期回滚一天，也就是最后一天
        MaxDate = cd.get(Calendar.DATE);
        if (monthOfNumber == 1) {
            return -MaxDate;
        } else {
            return 1 - monthOfNumber;
        }
    }

    /**
     * 获得上月最后一天的日期
     */
    public String getPreviousMonthEnd() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.MONTH, -1);// 减一个月
        lastDate.set(Calendar.DATE, 1);// 把日期设置为当月第一天
        lastDate.roll(Calendar.DATE, -1);// 日期回滚一天，也就是本月最后一天
        str = sdf.format(lastDate.getTime());
        return str;
    }

    /**
     * 获得下个月第一天的日期
     */
    public String getNextMonthFirst() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.MONTH, 1);// 减一个月
        lastDate.set(Calendar.DATE, 1);// 把日期设置为当月第一天
        str = sdf.format(lastDate.getTime());
        return str;
    }

    /**
     * 获得下个月最后一天的日期
     */
    public String getNextMonthEnd() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.MONTH, 1);// 加一个月
        lastDate.set(Calendar.DATE, 1);// 把日期设置为当月第一天
        lastDate.roll(Calendar.DATE, -1);// 日期回滚一天，也就是本月最后一天
        str = sdf.format(lastDate.getTime());
        return str;
    }

    /**
     * 获得明年最后一天的日期
     */
    public String getNextYearEnd() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.YEAR, 1);// 加一个年
        lastDate.set(Calendar.DAY_OF_YEAR, 1);
        lastDate.roll(Calendar.DAY_OF_YEAR, -1);
        str = sdf.format(lastDate.getTime());
        return str;
    }

    /**
     * 获得明年第一天的日期
     */
    public String getNextYearFirst() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.YEAR, 1);// 加一个年
        lastDate.set(Calendar.DAY_OF_YEAR, 1);
        str = sdf.format(lastDate.getTime());
        return str;
    }

    /**
     * 获得本年有多少天
     * 
     * @return
     */
    private int getMaxYear() {
        Calendar cd = Calendar.getInstance();
        cd.set(Calendar.DAY_OF_YEAR, 1);// 把日期设为当年第一天
        cd.roll(Calendar.DAY_OF_YEAR, -1);// 把日期回滚一天。
        int MaxYear = cd.get(Calendar.DAY_OF_YEAR);
        return MaxYear;
    }

    private int getYearPlus() {
        Calendar cd = Calendar.getInstance();
        int yearOfNumber = cd.get(Calendar.DAY_OF_YEAR);// 获得当天是一年中的第几天
        cd.set(Calendar.DAY_OF_YEAR, 1);// 把日期设为当年第一天
        cd.roll(Calendar.DAY_OF_YEAR, -1);// 把日期回滚一天。
        int MaxYear = cd.get(Calendar.DAY_OF_YEAR);
        if (yearOfNumber == 1) {
            return -MaxYear;
        } else {
            return 1 - yearOfNumber;
        }
    }

    /**
     * 获得本年第一天的日期
     * 
     * @return
     */
    public String getCurrentYearFirst() {
        int yearPlus = this.getYearPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, yearPlus);
        Date yearDay = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preYearDay = df.format(yearDay);
        return preYearDay;
    }

    /**
     * 获得本年最后一天的日期
     * 
     * @return
     */
    public String getCurrentYearEnd() {
        Date date = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
        String years = dateFormat.format(date);
        return years + "-12-31";
    }

    /**
     * 获得上年第一天的日期
     * 
     * @return
     */
    public String getPreviousYearFirst() {
        Date date = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
        String years = dateFormat.format(date);
        int years_value = Integer.parseInt(years);
        years_value--;
        return years_value + "-1-1";
    }

    /**
     * 获得上年最后一天的日期
     * 
     * @return
     */
    public String getPreviousYearEnd() {
        weeks--;
        int yearPlus = this.getYearPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, yearPlus + MaxYear * weeks + (MaxYear - 1));
        Date yearDay = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preYearDay = df.format(yearDay);
        getThisSeasonTime(11);
        return preYearDay;
    }

    /**
     * 获得本季度
     * 
     * @param month
     * @return
     */
    public String getThisSeasonTime(int month) {
        int array[][] = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 }, { 10, 11, 12 } };
        int season = 1;
        if (month >= 1 && month <= 3) {
            season = 1;
        }
        if (month >= 4 && month <= 6) {
            season = 2;
        }
        if (month >= 7 && month <= 9) {
            season = 3;
        }
        if (month >= 10 && month <= 12) {
            season = 4;
        }
        int start_month = array[season - 1][0];
        int end_month = array[season - 1][2];
        Date date = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
        String years = dateFormat.format(date);
        int years_value = Integer.parseInt(years);
        int start_days = 1;// years+"-"+String.valueOf(start_month)+"-1";//getLastDayOfMonth(years_value,start_month);
        int end_days = getLastDayOfMonth(years_value, end_month);
        String seasonDate = years_value + "-" + start_month + "-" + start_days + ";" + years_value + "-" + end_month + "-" + end_days;
        return seasonDate;
    }

    /**
     * 获取某年某月的最后一天
     * 
     * @param year
     *            年
     * @param month
     *            月
     * @return 最后一天
     */
    private int getLastDayOfMonth(int year, int month) {
        if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) {
            return 31;
        }
        if (month == 4 || month == 6 || month == 9 || month == 11) {
            return 30;
        }
        if (month == 2) {
            if (isLeapYear(year)) {
                return 29;
            } else {
                return 28;
            }
        }
        return 0;
    }

    /**
     * 是否闰年
     * 
     * @param year
     *            年
     * @return
     */
    public boolean isLeapYear(int year) {
        return (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
    }
}