Java Date processing Tool class _java

This article aims at the date processing to study uses, mainly divides into two parts, below for everybody specific introduction

The first part: The basics of date processing

Date class
Role: The main function is to obtain the current time
Convert a date to a standard format

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");

Converts a string to a date type

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 June 10:30:30 CST 2014");

The application of the Calendar class

The Java.util.Calendar class is an abstract class that can get a Calendar object by calling the GetInstance () static method, which is initialized by the current date time, which is the default representing the current time

 Calendar C = calendar.getinstance ();
int year = C.get (calender.year);
int month= c.get (calender.month) +1; Gets the month, 0 means January
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);

Compare 2 month of time difference

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 ()));

Part II: Date Processing tool class

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;  /** * Date processing tool class * @author Dylan_xu * @date, * @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 "; 
  /** date format YYYY-MM string constant */private static final String Month_format = "yyyy-mm"; /** date format YYYY-MM-DD string constant */PRivate static final String date_format = "YYYY-MM-DD"; 
  /** date format HH:mm:ss string constant */private static final String Hour_format = "HH:mm:ss"; 
  /** Date format YYYY-MM-DD HH:MM:SS string constant */private static final String Datetime_format = "Yyyy-mm-dd HH:mm:ss"; 
  /** one day at the beginning of the minute string constant 00:00:00/private static final String Day_begin_string_hhmmss = "00:00:00"; 
  /** the end of the day, the seconds string constant 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 () {}/ 
   * * * Get the server's current date and time, in the format of: Yyyy-mm-dd HH:mm:ss Date String form return * @author Dylan_xu * @date * @return * * public staticString GetDateTime () {try {return Sdf_datetime_format.format (Cale.gettime ()); 
      catch (Exception e) {logger.debug ("Dateutil.getdatetime ():" + e.getmessage ()); 
    Return ""; 
   /** * Gets the server's current date in the format of: yyyy-mm-dd date string return * @author Dylan_xu * @date * @return 
    */public static String GetDate () {try {return Sdf_date_format.format (Cale.gettime ()); 
      catch (Exception e) {logger.debug ("dateutil.getdate ():" + e.getmessage ()); 
    Return ""; 
   /** * Gets the server's current time and returns it in the form of a date string of HH:mm:ss * @author Dylan_xu * @date * @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 ""; }}/** * Statistics The default value of the start date * @author Dylan_xu *@date Mar * @return/public static String Getstartdate () {try {return getyear () + "-01 
    -01 "; 
      catch (Exception e) {logger.debug ("dateutil.getstartdate ():" + e.getmessage ()); 
    Return ""; }/** * Statistics The default value of the end date * @author Dylan_xu * @date, * @return/public static S 
    Tring Getenddate () {try {return getDate (); 
      catch (Exception e) {logger.debug ("dateutil.getenddate ():" + e.getmessage ()); 
    Return ""; /** * Get the year of the server's current date * @author Dylan_xu * @date-@return * * * public static 
    String getyear () {try {return string.valueof (Cale.get (calendar.year)); 
      catch (Exception e) {logger.debug ("dateutil.getyear ():" + e.getmessage ()); 
    Return ""; /** * Get the month of the server's current date * @author Dylan_xu * @date-@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 ""; }/** * Get server days in the current month * @author Dylan_xu * @date (*) @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 ""; 
   }/** * Compare two days of difference * @author Dylan_xu * @date Mar, * @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; 
   }/** * Compare two days of difference * @author Dylan_xu * @date Mar, * @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; }/** * Compares the number of months that differ by two dates 
   * @date @author Dylan_xu * @param date1 * @param date2 * @return * * Public stat 
    IC 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; }/** * Return date plus x Day * @author Dylan_xu * @date Mar, * @param date * @param i * @return */public static string Addday (String date, int i) {try {GregorianCalendar gCal = new Gregori  
          Ancalendar (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 (); }/** * Return date plus x-month date * @author Dylan_xu * @date Mar, * @param date * @param i * @return */public static string Addmonth (String date, int i) {try {GregorianCalendar gCal = new Grego  
          Riancalendar (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 (); */** * return date plus x year date * @author Dylan_xu * @date Mar, * @param date * @param i * 
 @return  */public static string Addyear (String date, int i) {try {GregorianCalendar gCal = new Gregoriancalenda  
          R (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 ""; 
   }/** * Returns the maximum day of the month of the year * @author Dylan_xu * @date Mar, * @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 = 
      nth = = 31; 
      else if (Imonth = 4 | | imonth = 6 | | | imonth = 9 | | imonth = one) {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; }/** * Format date * @author Dylan_xu * @date (*) @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 > One) {imonth = 0; 
      } iday = Integer.parseint (temp); 
  
      if (Iday < 1 | | | iday >) iday = 1; 
      Calendar Orgcale = Calendar.getinstance (); 
      Orgcale.set (Iyear, Imonth, iday); 
      temp = This.rolldate (Orgcale, Type, Span); 
    return temp; 
    catch (Exception e) {return ""; 
      The 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 ""; }/** * Returns the default date format * @author Dylan_xu * @date-@return */public static SYN 
    chronized String Getdatepattern () {Defaultdatepattern = "yyyy-mm-dd"; 
  return defaultdatepattern; 
   /** * To format the specified date in the default format into a string and output such as: YYYY-MM-DD * @author dylan_xu * @date * @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); /** * Gets the time string for the given date, in the current default time format * @author Dylan_xu * @date * @param thetime * @ret 
  URN */public static String Gettimenow (Date thetime) {return GetDateTime (Timepattern, thetime); /** * Get the Calendar Calendar object for the current time * @author Dylan_xu * @date Mar * @return * @throws parseexception/public Calendar Gettoday () throws ParseException {Dat 
    E today = new Date (); 
    SimpleDateFormat df = new SimpleDateFormat (Getdatepattern ()); 
    String todayasstring = Df.format (today); 
    Calendar cal = new GregorianCalendar (); 
    Cal.settime (Convertstringtodate (todayasstring)); 
  Return cal; 
   /** * Converts a date class to a string form of the specified format * @author Dylan_xu * @date-@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); 
   /** * Converts the specified date to a string form of the default format * @author Dylan_xu * @date-@param adate * @return * * public static finalString convertdatetostring (Date adate) {return GetDateTime (Getdatepattern (), adate); /** * Converts date strings to date types in the specified format * @author Dylan_xu * @date Mar, * @param amask specified date format, such as: yyyy-mm- DD * @param strdate Date string to be converted * @return * @throws parseexception * * public static final date Convertstr 
    Ingtodate (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); 
   /** * Converts a date string to the date type by default format * @author Dylan_xu * @date-@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;  /** * Returns a Java simple Type date string * @author Dylan_xu * @date-@return/public static 
    String Getsimpledateformat () {SimpleDateFormat formatter = new SimpleDateFormat (); 
    String ndatetime = Formatter.format (New Date ()); 
  return ndatetime; /** * Compares the date specified in the string format with the current time * @author DYLAN * @date Feb, * @param strdate need to compare time * @ret URN * <p> * int code * <ul> * <li>-1 Current time < comparison time </li> * <li> 0 Current time = comparison time </li> * <li>>=1 Current time > comparison time </li> * </ul> * </p>/public static int comparetocurtime (String strdate) {if stringutils.i 
    Sblank (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 +" ' t 
      o A date, throwing exception: "+ e.getlocalizedmessage () +"]); 
    } if (Stringutils.isnotblank (Strcurtime)) {return Strcurtime.compareto (strdate); 
  } return-1; /** * Add minimum time for query date * * @param target Type Date * @param conversion parameter Date * @return * * @SuppressWarning 
    S ("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; }/** * Add maximum time to query date * * @param target Type Date * @param conversion parameter date * @return/@SuppressWarn 
    Ings ("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; }/** * Returns the number of days of the specified month in the current year * * @param month month * @return Total days of the specified month * * * @SuppressWarnings ("Depr 
    Ecation ") 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, 3 
    1, 30, 31}}; 
    int year = Date.getyear () + 1900; if (year% 4 = 0 && Year%!= 0 | | [Year% = = 0) {return day[1][month] + ""; 
    else {return day[0][month] + ""; }/** * Returns the number of days specified in the specified year * * @param years Year * @param month month * @return The total number of days in a specified month * * * publi C Static String getmonthlastday (int month) {int[][] day = {0, 30, 28, 31, 30, 31, 30, 31, 31, 30, 31, 3 
    0, 31}, {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}}; 
    if (year% 4 = 0 && Year%!= 0 | |-year% = = 0) {return day[1][month] + ""; 
    else {return day[0][month] + ""; 
  }/** * Judgment is excepting or leap year * @author Dylan_xu * @date-@param year * @return * * public static Boolean isleapyear (int year) {if (year% 4 = 0 && Year% 100!= 0) | | 
    (year%) = = 0) {return true; 
    else {return false; }/** * Postmarks * @author dylan_xu * @date * @return * * @SuppressWarnings ("deprecation") public static STRing Gettimestamp () {Date date = Cale.gettime (); String timestamp = "" + (Date.getyear () + 1900) + date.getmonth () + date.getdate () + date.getminutes () + Date.get 
    Seconds () + date.gettime (); 
  return timestamp; /** * postmarks * * * @return * * * @SuppressWarnings ("deprecation") public static String for the specified time GetTime Stamp (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 ());  } 
}

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