java日期处理工具类

本文针对日期处理进行学习使用，主要分为两部分，下面为大家具体介绍一下

第一部分：日期处理基础知识

Date 类
作用：最主要的作用就是获得当前时间
将日期转换为标准格式

Date date = new Date();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String str = sdf.format(date);
System.out.println(“2015-10-16 14:59:52”);

将String转换为Date类型

String day = "2014-6-5 10:30:30";
SimpleDateFormat d2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date date2 = d2.parse(day);
System.out.println(“Thu Jun 05 10:30:30 CST 2014”);

Calendar 类的应用

java.util.Calendar 类是一个抽象类，可以通过调用 getInstance() 静态方法获取一个 Calendar 对象，此对象已由当前日期时间初始化，即默认代表当前时间

Calendar c = Calendar.getInstance();
int year = c.get(Calender.YEAR);
int month= c.get(Calender.MONTH)+1; //获取月份，0表示1月份
int day = c.get(Calender.DAY_OF_MONTH);
int hour= c.get(Calender.HOUR_OF_DAY);
int minute= c.get(Calender.MINUTE);
int second = c.get(Calender.SECOND);

比较2个时间相差的月份

SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
DateTime d1 = new DateTime(format.parse("2016-10-31 00:00:00"));
DateTime d2 = new DateTime(format.parse("2015-1-31 00:00:00"));
System.out.println(Math.abs(Months.monthsBetween(d1,d2).getMonths()));

第二部分：日期处理工具类

package com.analysys.website.control;

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

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

/**
 * 日期处理工具类
 * @author dylan_xu
 * @date Mar 11, 2012
 * @modified by
 * @modified date
 * @since JDK1.6
 * @see com.util.DateUtil
 */

public class DateUtil {
  // ~ Static fields/initializers
  // =============================================

  private static Logger logger = Logger.getLogger(DateUtil.class);
  private static String defaultDatePattern = null;
  private static String timePattern = "HH:mm";
  private static Calendar cale = Calendar.getInstance();
  public static final String TS_FORMAT = DateUtil.getDatePattern() + " HH:mm:ss.S";
  /** 日期格式yyyy-MM字符串常量 */
  private static final String MONTH_FORMAT = "yyyy-MM";
  /** 日期格式yyyy-MM-dd字符串常量 */
  private static final String DATE_FORMAT = "yyyy-MM-dd";
  /** 日期格式HH:mm:ss字符串常量 */
  private static final String HOUR_FORMAT = "HH:mm:ss";
  /** 日期格式yyyy-MM-dd HH:mm:ss字符串常量 */
  private static final String DATETIME_FORMAT = "yyyy-MM-dd HH:mm:ss";
  /** 某天开始时分秒字符串常量 00:00:00 */
  private static final String DAY_BEGIN_STRING_HHMMSS = " 00:00:00";
  /** 某天结束时分秒字符串常量 23:59:59 */
  public static final String DAY_END_STRING_HHMMSS = " 23:59:59";
  private static SimpleDateFormat sdf_date_format = new SimpleDateFormat(DATE_FORMAT);
  private static SimpleDateFormat sdf_hour_format = new SimpleDateFormat(HOUR_FORMAT);
  private static SimpleDateFormat sdf_datetime_format = new SimpleDateFormat(DATETIME_FORMAT);


  // ~ Methods
  // ================================================================

  public DateUtil() {
  }

  /**
   * 获得服务器当前日期及时间，以格式为：yyyy-MM-dd HH:mm:ss的日期字符串形式返回
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static String getDateTime() {
    try {
      return sdf_datetime_format.format(cale.getTime());
    } catch (Exception e) {
      logger.debug("DateUtil.getDateTime():" + e.getMessage());
      return "";
    }
  }

  /**
   * 获得服务器当前日期，以格式为：yyyy-MM-dd的日期字符串形式返回
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static String getDate() {
    try {
      return sdf_date_format.format(cale.getTime());
    } catch (Exception e) {
      logger.debug("DateUtil.getDate():" + e.getMessage());
      return "";
    }
  }

  /**
   * 获得服务器当前时间，以格式为：HH:mm:ss的日期字符串形式返回
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static String getTime() {
    String temp = " ";
    try {
      temp += sdf_hour_format.format(cale.getTime());
      return temp;
    } catch (Exception e) {
      logger.debug("DateUtil.getTime():" + e.getMessage());
      return "";
    }
  }

  /**
   * 统计时开始日期的默认值
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static String getStartDate() {
    try {
      return getYear() + "-01-01";
    } catch (Exception e) {
      logger.debug("DateUtil.getStartDate():" + e.getMessage());
      return "";
    }
  }

  /**
   * 统计时结束日期的默认值
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static String getEndDate() {
    try {
      return getDate();
    } catch (Exception e) {
      logger.debug("DateUtil.getEndDate():" + e.getMessage());
      return "";
    }
  }

  /**
   * 获得服务器当前日期的年份
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static String getYear() {
    try {
      return String.valueOf(cale.get(Calendar.YEAR));
    } catch (Exception e) {
      logger.debug("DateUtil.getYear():" + e.getMessage());
      return "";
    }
  }

  /**
   * 获得服务器当前日期的月份
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static String getMonth() {
    try {
      java.text.DecimalFormat df = new java.text.DecimalFormat();
      df.applyPattern("00;00");
      return df.format((cale.get(Calendar.MONTH) + 1));
    } catch (Exception e) {
      logger.debug("DateUtil.getMonth():" + e.getMessage());
      return "";
    }
  }

  /**
   * 获得服务器在当前月中天数
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static String getDay() {
    try {
      return String.valueOf(cale.get(Calendar.DAY_OF_MONTH));
    } catch (Exception e) {
      logger.debug("DateUtil.getDay():" + e.getMessage());
      return "";
    }
  }

  /**
   * 比较两个日期相差的天数
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param date1
   * @param date2
   * @return
   */
  public static int getMargin(String date1, String date2) {
    int margin;
    try {
      ParsePosition pos = new ParsePosition(0);
      ParsePosition pos1 = new ParsePosition(0);
      Date dt1 = sdf_date_format.parse(date1, pos);
      Date dt2 = sdf_date_format.parse(date2, pos1);
      long l = dt1.getTime() - dt2.getTime();
      margin = (int) (l / (24 * 60 * 60 * 1000));
      return margin;
    } catch (Exception e) {
      logger.debug("DateUtil.getMargin():" + e.toString());
      return 0;
    }
  }

  /**
   * 比较两个日期相差的天数
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param date1
   * @param date2
   * @return
   */
  public static double getDoubleMargin(String date1, String date2) {
    double margin;
    try {
      ParsePosition pos = new ParsePosition(0);
      ParsePosition pos1 = new ParsePosition(0);
      Date dt1 = sdf_datetime_format.parse(date1, pos);
      Date dt2 = sdf_datetime_format.parse(date2, pos1);
      long l = dt1.getTime() - dt2.getTime();
      margin = (l / (24 * 60 * 60 * 1000.00));
      return margin;
    } catch (Exception e) {
      logger.debug("DateUtil.getMargin():" + e.toString());
      return 0;
    }
  }

  /**
   * 比较两个日期相差的月数
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param date1
   * @param date2
   * @return
   */
  public static int getMonthMargin(String date1, String date2) {
    int margin;
    try {
      margin = (Integer.parseInt(date2.substring(0, 4)) - Integer.parseInt(date1.substring(0, 4))) * 12;
      margin += (Integer.parseInt(date2.substring(4, 7).replaceAll("-0",
          "-")) - Integer.parseInt(date1.substring(4, 7).replaceAll("-0", "-")));
      return margin;
    } catch (Exception e) {
      logger.debug("DateUtil.getMargin():" + e.toString());
      return 0;
    }
  }

  /**
   * 返回日期加X天后的日期
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param date
   * @param i
   * @return
   */
  public static String addDay(String date, int i) {
    try {
      GregorianCalendar gCal = new GregorianCalendar(
          Integer.parseInt(date.substring(0, 4)),
          Integer.parseInt(date.substring(5, 7)) - 1,
          Integer.parseInt(date.substring(8, 10)));
      gCal.add(GregorianCalendar.DATE, i);
      return sdf_date_format.format(gCal.getTime());
    } catch (Exception e) {
      logger.debug("DateUtil.addDay():" + e.toString());
      return getDate();
    }
  }

  /**
   * 返回日期加X月后的日期
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param date
   * @param i
   * @return
   */
  public static String addMonth(String date, int i) {
    try {
      GregorianCalendar gCal = new GregorianCalendar(
          Integer.parseInt(date.substring(0, 4)),
          Integer.parseInt(date.substring(5, 7)) - 1,
          Integer.parseInt(date.substring(8, 10)));
      gCal.add(GregorianCalendar.MONTH, i);
      return sdf_date_format.format(gCal.getTime());
    } catch (Exception e) {
      logger.debug("DateUtil.addMonth():" + e.toString());
      return getDate();
    }
  }

  /**
   * 返回日期加X年后的日期
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param date
   * @param i
   * @return
   */
  public static String addYear(String date, int i) {
    try {
      GregorianCalendar gCal = new GregorianCalendar(
          Integer.parseInt(date.substring(0, 4)),
          Integer.parseInt(date.substring(5, 7)) - 1,
          Integer.parseInt(date.substring(8, 10)));
      gCal.add(GregorianCalendar.YEAR, i);
      return sdf_date_format.format(gCal.getTime());
    } catch (Exception e) {
      logger.debug("DateUtil.addYear():" + e.toString());
      return "";
    }
  }

  /**
   * 返回某年某月中的最大天
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param year
   * @param month
   * @return
   */
  public static int getMaxDay(int iyear, int imonth) {
    int day = 0;
    try {
      if (imonth == 1 || imonth == 3 || imonth == 5 || imonth == 7
          || imonth == 8 || imonth == 10 || imonth == 12) {
        day = 31;
      } else if (imonth == 4 || imonth == 6 || imonth == 9 || imonth == 11) {
        day = 30;
      } else if ((0 == (iyear % 4)) && (0 != (iyear % 100)) || (0 == (iyear % 400))) {
        day = 29;
      } else {
        day = 28;
      }
      return day;
    } catch (Exception e) {
      logger.debug("DateUtil.getMonthDay():" + e.toString());
      return 1;
    }
  }

  /**
   * 格式化日期
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param orgDate
   * @param Type
   * @param Span
   * @return
   */
  @SuppressWarnings("static-access")
  public String rollDate(String orgDate, int Type, int Span) {
    try {
      String temp = "";
      int iyear, imonth, iday;
      int iPos = 0;
      char seperater = '-';
      if (orgDate == null || orgDate.length() < 6) {
        return "";
      }

      iPos = orgDate.indexOf(seperater);
      if (iPos > 0) {
        iyear = Integer.parseInt(orgDate.substring(0, iPos));
        temp = orgDate.substring(iPos + 1);
      } else {
        iyear = Integer.parseInt(orgDate.substring(0, 4));
        temp = orgDate.substring(4);
      }

      iPos = temp.indexOf(seperater);
      if (iPos > 0) {
        imonth = Integer.parseInt(temp.substring(0, iPos));
        temp = temp.substring(iPos + 1);
      } else {
        imonth = Integer.parseInt(temp.substring(0, 2));
        temp = temp.substring(2);
      }

      imonth--;
      if (imonth < 0 || imonth > 11) {
        imonth = 0;
      }

      iday = Integer.parseInt(temp);
      if (iday < 1 || iday > 31)
        iday = 1;

      Calendar orgcale = Calendar.getInstance();
      orgcale.set(iyear, imonth, iday);
      temp = this.rollDate(orgcale, Type, Span);
      return temp;
    } catch (Exception e) {
      return "";
    }
  }

  public static String rollDate(Calendar cal, int Type, int Span) {
    try {
      String temp = "";
      Calendar rolcale;
      rolcale = cal;
      rolcale.add(Type, Span);
      temp = sdf_date_format.format(rolcale.getTime());
      return temp;
    } catch (Exception e) {
      return "";
    }
  }

  /**
   * 返回默认的日期格式
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static synchronized String getDatePattern() {
    defaultDatePattern = "yyyy-MM-dd";
    return defaultDatePattern;
  }

  /**
   * 将指定日期按默认格式进行格式代化成字符串后输出如：yyyy-MM-dd
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param aDate
   * @return
   */
  public static final String getDate(Date aDate) {
    SimpleDateFormat df = null;
    String returnValue = "";
    if (aDate != null) {
      df = new SimpleDateFormat(getDatePattern());
      returnValue = df.format(aDate);
    }
    return (returnValue);
  }

  /**
   * 取得给定日期的时间字符串，格式为当前默认时间格式
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param theTime
   * @return
   */
  public static String getTimeNow(Date theTime) {
    return getDateTime(timePattern, theTime);
  }

  /**
   * 取得当前时间的Calendar日历对象
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   * @throws ParseException
   */
  public Calendar getToday() throws ParseException {
    Date today = new Date();
    SimpleDateFormat df = new SimpleDateFormat(getDatePattern());
    String todayAsString = df.format(today);
    Calendar cal = new GregorianCalendar();
    cal.setTime(convertStringToDate(todayAsString));
    return cal;
  }

  /**
   * 将日期类转换成指定格式的字符串形式
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param aMask
   * @param aDate
   * @return
   */
  public static final String getDateTime(String aMask, Date aDate) {
    SimpleDateFormat df = null;
    String returnValue = "";

    if (aDate == null) {
      logger.error("aDate is null!");
    } else {
      df = new SimpleDateFormat(aMask);
      returnValue = df.format(aDate);
    }
    return (returnValue);
  }

  /**
   * 将指定的日期转换成默认格式的字符串形式
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param aDate
   * @return
   */
  public static final String convertDateToString(Date aDate) {
    return getDateTime(getDatePattern(), aDate);
  }

  /**
   * 将日期字符串按指定格式转换成日期类型
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param aMask 指定的日期格式，如:yyyy-MM-dd
   * @param strDate 待转换的日期字符串
   * @return
   * @throws ParseException
   */
  public static final Date convertStringToDate(String aMask, String strDate)
      throws ParseException {
    SimpleDateFormat df = null;
    Date date = null;
    df = new SimpleDateFormat(aMask);

    if (logger.isDebugEnabled()) {
      logger.debug("converting '" + strDate + "' to date with mask '" + aMask + "'");
    }
    try {
      date = df.parse(strDate);
    } catch (ParseException pe) {
      logger.error("ParseException: " + pe);
      throw pe;
    }
    return (date);
  }

  /**
   * 将日期字符串按默认格式转换成日期类型
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param strDate
   * @return
   * @throws ParseException
   */
  public static Date convertStringToDate(String strDate)
      throws ParseException {
    Date aDate = null;

    try {
      if (logger.isDebugEnabled()) {
        logger.debug("converting date with pattern: " + getDatePattern());
      }
      aDate = convertStringToDate(getDatePattern(), strDate);
    } catch (ParseException pe) {
      logger.error("Could not convert '" + strDate + "' to a date, throwing exception");
      throw new ParseException(pe.getMessage(), pe.getErrorOffset());
    }
    return aDate;
  }

  /**
   * 返回一个JAVA简单类型的日期字符串
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  public static String getSimpleDateFormat() {
    SimpleDateFormat formatter = new SimpleDateFormat();
    String NDateTime = formatter.format(new Date());
    return NDateTime;
  }

  /**
   * 将指定字符串格式的日期与当前时间比较
   * @author DYLAN
   * @date Feb 17, 2012
   * @param strDate 需要比较时间
   * @return
   *   <p>
   *   int code
   *   <ul>
   *   <li>-1 当前时间 < 比较时间 </li>
   *   <li> 0 当前时间 = 比较时间 </li>
   *   <li>>=1当前时间 > 比较时间 </li>
   *   </ul>
   *   </p>
   */
  public static int compareToCurTime (String strDate) {
    if (StringUtils.isBlank(strDate)) {
      return -1;
    }
    Date curTime = cale.getTime();
    String strCurTime = null;
    try {
      strCurTime = sdf_datetime_format.format(curTime);
    } catch (Exception e) {
      if (logger.isDebugEnabled()) {
        logger.debug("[Could not format '" + strDate + "' to a date, throwing exception:" + e.getLocalizedMessage() + "]");
      }
    }
    if (StringUtils.isNotBlank(strCurTime)) {
      return strCurTime.compareTo(strDate);
    }
    return -1;
  }

  /**
   * 为查询日期添加最小时间
   *
   * @param 目标类型Date
   * @param 转换参数Date
   * @return
   */
  @SuppressWarnings("deprecation")
  public static Date addStartTime(Date param) {
    Date date = param;
    try {
      date.setHours(0);
      date.setMinutes(0);
      date.setSeconds(0);
      return date;
    } catch (Exception ex) {
      return date;
    }
  }

  /**
   * 为查询日期添加最大时间
   *
   * @param 目标类型Date
   * @param 转换参数Date
   * @return
   */
  @SuppressWarnings("deprecation")
  public static Date addEndTime(Date param) {
    Date date = param;
    try {
      date.setHours(23);
      date.setMinutes(59);
      date.setSeconds(0);
      return date;
    } catch (Exception ex) {
      return date;
    }
  }

  /**
   * 返回系统现在年份中指定月份的天数
   *
   * @param 月份month
   * @return 指定月的总天数
   */
  @SuppressWarnings("deprecation")
  public static String getMonthLastDay(int month) {
    Date date = new Date();
    int[][] day = { { 0, 30, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
        { 0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } };
    int year = date.getYear() + 1900;
    if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) {
      return day[1][month] + "";
    } else {
      return day[0][month] + "";
    }
  }

  /**
   * 返回指定年份中指定月份的天数
   *
   * @param 年份year
   * @param 月份month
   * @return 指定月的总天数
   */
  public static String getMonthLastDay(int year, int month) {
    int[][] day = { { 0, 30, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
        { 0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } };
    if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) {
      return day[1][month] + "";
    } else {
      return day[0][month] + "";
    }
  }

  /**
   * 判断是平年还是闰年
   * @author dylan_xu
   * @date Mar 11, 2012
   * @param year
   * @return
   */
  public static boolean isLeapyear(int year) {
    if ((year % 4 == 0 && year % 100 != 0) || (year % 400) == 0) {
      return true;
    } else {
      return false;
    }
  }

  /**
   * 取得当前时间的日戳
   * @author dylan_xu
   * @date Mar 11, 2012
   * @return
   */
  @SuppressWarnings("deprecation")
  public static String getTimestamp() {
    Date date = cale.getTime();
    String timestamp = "" + (date.getYear() + 1900) + date.getMonth()
        + date.getDate() + date.getMinutes() + date.getSeconds()
        + date.getTime();
    return timestamp;
  }

  /**
   * 取得指定时间的日戳
   *
   * @return
   */
  @SuppressWarnings("deprecation")
  public static String getTimestamp(Date date) {
    String timestamp = "" + (date.getYear() + 1900) + date.getMonth()
        + date.getDate() + date.getMinutes() + date.getSeconds()
        + date.getTime();
    return timestamp;
  }

  public static void main(String[] args) {
    System.out.println(getYear() + "|" + getMonth() + "|" + getDate());
  }
}

以上就是本文的全部内容，希望对大家的学习有所帮助。