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。