時間相關的工具類

package com.gameqp.common;

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

/**
 * @ClassName: DateUtils
 * @Description: 日期工具類
 * @author duhai
 * @date 2017年10月26日 上午11:24:37
 */
public class MyDateUtils {

    /**
     * 獲取上週一
     *
     * @param date
     * @return
     */
    public static Date geLastWeekMonday(Date date) {
        Calendar cal = Calendar.getInstance();
        cal.setTime(getThisWeekMonday(date));
        cal.add(Calendar.DATE, -7);
        return cal.getTime();
    }

    /**
     * 獲取本週一
     *
     * @param date
     * @return
     */
    public static Date getThisWeekMonday(Date date) {
        Calendar cal = Calendar.getInstance();
        cal.setTime(date);
        // 獲得當前日期是一個星期的第幾天
        int dayWeek = cal.get(Calendar.DAY_OF_WEEK);
        if (1 == dayWeek) {
            cal.add(Calendar.DAY_OF_MONTH, -1);
        }
        // 設定一個星期的第一天，按中國的習慣一個星期的第一天是星期一
        cal.setFirstDayOfWeek(Calendar.MONDAY);
        // 獲得當前日期是一個星期的第幾天
        int day = cal.get(Calendar.DAY_OF_WEEK);
        // 根據日曆的規則，給當前日期減去星期幾與一個星期第一天的差值
        cal.add(Calendar.DATE, cal.getFirstDayOfWeek() - day);
        return cal.getTime();
    }

    /**
     * 獲取下週一
     *
     * @param date
     * @return
     */
    public static Date getNextWeekMonday(Date date) {
        Calendar cal = Calendar.getInstance();
        cal.setTime(getThisWeekMonday(date));
        cal.add(Calendar.DATE, 7);
        return cal.getTime();
    }

    /**
     * 獲取上週一
     *
     * @param dateString
     *            日期字串 比如：2017-10-26
     * @return
     * @throws ParseException
     */
    public static Date geLastWeekMonday(String dateString) throws ParseException {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = sdf.parse(dateString + " 00:00:00");
        Calendar cal = Calendar.getInstance();
        cal.setTime(getThisWeekMonday(date));
        cal.add(Calendar.DATE, -7);
        return cal.getTime();
    }

    /**
     * 獲取本週一
     *
     * @param dateString
     *            日期字串 比如：2017-10-26
     * @return
     * @throws ParseException
     */
    public static Date getThisWeekMonday(String dateString) throws ParseException {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = sdf.parse(dateString + " 00:00:00");
        Calendar cal = Calendar.getInstance();
        cal.setTime(date);
        // 獲得當前日期是一個星期的第幾天
        int dayWeek = cal.get(Calendar.DAY_OF_WEEK);
        if (1 == dayWeek) {
            cal.add(Calendar.DAY_OF_MONTH, -1);
        }
        // 設定一個星期的第一天，按中國的習慣一個星期的第一天是星期一
        cal.setFirstDayOfWeek(Calendar.MONDAY);
        // 獲得當前日期是一個星期的第幾天
        int day = cal.get(Calendar.DAY_OF_WEEK);
        // 根據日曆的規則，給當前日期減去星期幾與一個星期第一天的差值
        cal.add(Calendar.DATE, cal.getFirstDayOfWeek() - day);
        return cal.getTime();
    }

    /**
     * 獲取下週一
     *
     * @param dateString
     *            日期字串 比如：2017-10-26
     * @return
     */
    public static Date getNextWeekMonday(String dateString) throws ParseException {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = sdf.parse(dateString + " 00:00:00");
        Calendar cal = Calendar.getInstance();
        cal.setTime(getThisWeekMonday(date));
        cal.add(Calendar.DATE, 7);
        return cal.getTime();
    }

    /**
     * 按照型別獲取時間
     *
     * @param type
     *            0：上週一 1：本週一 2：下週一
     * @return
     * @throws ParseException
     */
    public static Date getWeekMondayByType(Integer type) throws ParseException {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String dateString = sdf.format(new Date()).substring(0, 10);
        Date date = null;
        if (type.equals(0)) {
            date = geLastWeekMonday(dateString);
        } else if (type.equals(1)) {
            date = getThisWeekMonday(dateString);
        } else if (type.equals(2)) {
            date = getNextWeekMonday(dateString);
        }
        return date;
    }

    public static void main(String[] args) {
        try {
            System.out.println("上週一" + getWeekMondayByType(0));
            System.out.println("本週一" + getWeekMondayByType(1));
            System.out.println("下週一" + getWeekMondayByType(2));
        } catch (ParseException e) {
            e.printStackTrace();
        }

    }

    public static void main2(String[] args) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        try {
            String dateString = "2017-10-26";
            System.out.println("今天是" + dateString);
            System.out.println("上週一" + sdf.format(geLastWeekMonday(dateString)));
            System.out.println("本週一" + sdf.format(getThisWeekMonday(dateString)));
            System.out.println("下週一" + sdf.format(getNextWeekMonday(dateString)));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void main1(String[] args) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        try {
            Date date = sdf.parse("2017-10-26 00:00:00");
            System.out.println("今天是" + sdf.format(date));
            System.out.println("上週一" + sdf.format(geLastWeekMonday(date)));
            System.out.println("本週一" + sdf.format(getThisWeekMonday(date)));
            System.out.println("下週一" + sdf.format(getNextWeekMonday(date)));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}