JSP, Tomcat, JDBC, Projects, Example, Program » Calendar

Java Calendar – How to get Month Name

admin — Wed, 20 May 2009 07:19:31 +0000

Java Calendar returns month in numeric integer format. To get month name in string (Jan, Feb, Mar, …), we have to use SimpleDateFormat class. First calendar date should convert into millisecond to parse into date object. SimpleDateFormat returns this date in month name string.

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

public class MonthName {

    public static void main(String[] args) {
        Calendar ca1 = Calendar.getInstance();

        // set(year, month, date) month 0-11
        ca1.set(2009, 05, 25);

        // int iMonth=ca1.get(Calendar.MONTH);

        java.util.Date d = new java.util.Date(ca1.getTimeInMillis());

        System.out.println("Month Name :"+new SimpleDateFormat("MMMM").format(d));
        System.out.println("Month Name :"+new SimpleDateFormat("MMM").format(d));
    }
}

Output

Month Name in String:June

Month Name in String :Jun

Java Calendar – How to find Week of Year

admin — Mon, 18 May 2009 09:02:32 +0000

In java calendar we can get week of year in Calendar.WEEK_OF_YEAR field.

Example will show to how to get week of year

import java.util.Calendar;

public class WeekOfYear {

    public static void main(String[] args) {

        Calendar ca1 = Calendar.getInstance();

        /*
        set(int year, int month, int date)
        Jan=0,Feb=1,Mar=2...
        */
        ca1.set(2009,4,22);

        int WEEK_OF_YEAR=ca1.get(Calendar.WEEK_OF_YEAR);

        System.out.println("WEEK OF YEAR :"+WEEK_OF_YEAR);
    }
}

Output

WEEK OF YEAR :21

Java Calendar – How to find Week of Month

admin — Mon, 18 May 2009 08:44:31 +0000

In java calendar we can get week of month in Calendar.WEEK_OF_MONTH field.

Example will show to how to get week of month

import java.util.Calendar;

public class WeekOfMonth {

    public static void main(String[] args) {
        Calendar ca1 = Calendar.getInstance();

        /*
        set(int year, int month, int date)
        Jan=0,Feb=1,Mar=2...
        */
        ca1.set(2009,4,22);

        int WEEK_OF_MONTH=ca1.get(Calendar.WEEK_OF_MONTH);
        System.out.println("Week of Month :"+WEEK_OF_MONTH);

        // More Calendar Date option can check
        /*
        int DAY_OF_MONTH=ca1.get(Calendar.DAY_OF_MONTH);
        int DAY_OF_WEEK=ca1.get(Calendar.DAY_OF_WEEK);
        int DAY_OF_YEAR=ca1.get(Calendar.DAY_OF_YEAR);
        int WEEK_OF_YEAR=ca1.get(Calendar.WEEK_OF_YEAR);
        */
    }
}

Output

Week of Month :4

Java Calendar – How to find Day of Year

admin — Mon, 18 May 2009 08:13:10 +0000

In java calendar we can get day of Year in Calendar.DAY_OF_YEAR field.

Example will show to how to get day of year

import java.util.Calendar;

public class DayOfYear {

    public static void main(String[] args) {
        Calendar ca1 = Calendar.getInstance();

        /*
        set(int year, int month, int date)
        Jan=0,Feb=1,Mar=2...
        */
        ca1.set(2009,4,22);

        /*
        2 Feb 2009, Day of Year, Jan 31 + 2 Feb =33 day of year
        */

        int DAY_OF_YEAR=ca1.get(Calendar.DAY_OF_YEAR);
        System.out.println("Day of Year :"+DAY_OF_YEAR);

        // More Calendar Date option can check
        /*
        int DAY_OF_MONTH=ca1.get(Calendar.DAY_OF_MONTH);
        int DAY_OF_WEEK=ca1.get(Calendar.DAY_OF_WEEK);
        int WEEK_OF_MONTH=ca1.get(Calendar.WEEK_OF_MONTH);
        int WEEK_OF_YEAR=ca1.get(Calendar.WEEK_OF_YEAR);
         */
    }
}

Output

Day of Year :142

Java Calendar – How to find Day of Week

admin — Mon, 18 May 2009 08:07:48 +0000

In java calendar we can get day of Week in Calendar.DAY_OF_WEEK field.

Example will show to how to get day of week

import java.util.Calendar;
import java.util.GregorianCalendar;

public class DayOfWeek {

    public static void main(String[] args) {
        Calendar ca1 = new GregorianCalendar();

        /*
        set(int year, int month, int date)
        Jan=0,Feb=1,Mar=2...
        */
        ca1.set(2009,04,22);

        /*
        Sunday Day of Week 1
        Monday Day of Week 2
        Tuesday Day of Week 3
        Wednesday Day of Week 4
        Thrusday Day of Week 5
        Friday Day of Week 6
        Saturday Day of Week 7
        */

        int DAY_OF_WEEK=ca1.get(Calendar.DAY_OF_WEEK);

        System.out.println("DAY OF WEEK :"+DAY_OF_WEEK);
    }
}

Java Calendar – How to get Day of Week in Month

admin — Sun, 17 May 2009 10:04:37 +0000

import java.util.Calendar;

public class DayOfWeekInMonth {

    public static void main(String[] args) {

        Calendar ca1 = Calendar.getInstance();

        ca1.set(2009, 6, 22);

        int DAY_OF_WEEK_IN_MONTH=ca1.get(Calendar.DAY_OF_WEEK_IN_MONTH);

        // More Calendar Date option can check
        /*
        int DAY_OF_MONTH=ca1.get(Calendar.DAY_OF_MONTH);
        int DAY_OF_WEEK=ca1.get(Calendar.DAY_OF_WEEK);
        int DAY_OF_YEAR=ca1.get(Calendar.DAY_OF_YEAR);
        int WEEK_OF_MONTH=ca1.get(Calendar.WEEK_OF_MONTH);
        int WEEK_OF_YEAR=ca1.get(Calendar.WEEK_OF_YEAR);
         */

        System.out.println("DAY OF WEEK IN MONTH :"+DAY_OF_WEEK_IN_MONTH);
    }
}

Java Calendar – How to get day month year in date

admin — Sun, 17 May 2009 10:02:02 +0000

We can get day, month and year from date object in Calendar. Calendar class gives us option to get day, month, and year separately in integer value. We have to use get() method of the calendar and pass value according to what we required in day, month or year from date.

Example of getting day, month and year in date

import java.util.Calendar;

public class GetDate {
    public static void main(String[] args) {

        Calendar ca1 = Calendar.getInstance();

        /// get day month year from set date
        ca1.set(2009, 05, 15); // dont set this date if current date is required

        int iDay=ca1.get(Calendar.DATE);
        int iMonth=ca1.get(Calendar.MONTH); // In Current date Add 1 in month
        int iYear=ca1.get(Calendar.YEAR);

        System.out.println("Day :"+iDay);
        System.out.println("Month :"+iMonth);
        System.out.println("Year :"+iYear);
    }
}

Output shown

Day :15
Month :5
Year :2009

Java – How to find date difference

admin — Sun, 17 May 2009 09:59:33 +0000

We can find date difference between two dates with converting dates into milliseconds by getTimeInMillis() method of java. To find date we have to calculate date difference in milliseconds.

If we minus two dates in millisecond, we will get date difference in milliseconds.

Example will help us to find days difference in two dates

import java.util.Calendar;

public class DateDiff {

    public static void main(String[] args) {

        Calendar ca1 = Calendar.getInstance();
        Calendar ca2 = Calendar.getInstance();

        // Set the date for both of the calendar to get difference
        ca1.set(2008, 07, 27);
        ca2.set(2009, 05, 15);

        // Get date in milliseconds
        long milisecond1 = ca1.getTimeInMillis();
        long milisecond2 = ca2.getTimeInMillis();

        // Find date difference in milliseconds
        long diffInMSec = milisecond2 - milisecond1;

        // Find date difference in days 
        // (24 hours 60 minutes 60 seconds 1000 millisecond)
        long diffOfDays = diffInMSec / (24 * 60 * 60 * 1000);

        System.out.println("Date Difference in : " + diffOfDays + " days.");

    }
}

JAVA – How to Add or Subtract Date

admin — Sun, 17 May 2009 09:56:30 +0000

In calendar, date can add and subtract with add method of Calendar in java. Java.util.Calendar class has a method to set date in object and after that we can add or subtract date according to requirement. We can add or subtract month, year and date with date option.

To subtract date, value should be passed with negative (-). This will reduce date from date.
To add date, value should be passed in positive. This will increase date from date.

In java program, we are adding 23 days in date. Month and Year is kept commented, will show that how to use add month and add year in date. To use this just do comment year and month.

First we are setting date in Calendar.

ca1.set(Year,Month,Date)

Adding & Subtracting Date

ca1.add(field, Value)

field = Calendar.DATE
field = Calendar.MONTH
field = Calendar.YEAR
value = any numeric value

import java.util.Calendar;

public class AddDate {

    public static void main(String[] args) {

    Calendar ca1 = Calendar.getInstance();
    ca1.set(2009,05,25);

    // Addition of date in java        
    ca1.add(Calendar.DATE, 23); // Add 23 days in Dates in Calendar
    //ca1.add(Calendar.MONTH, 2); // Add 2 Month in Date in Calendar
    //ca1.add(Calendar.YEAR, 4); // Add 4 Year in Date in Calendar

    /*
     *  Subtracting Date in Calendar
     *  
     *  ca1.add(Calendar.DATE, -23); // Subtracting 23 days from date
     *  //ca1.add(Calendar.MONTH, -2); // Subtracting 2 Month in Date in Calendar
     *  //ca1.add(Calendar.YEAR, -4); // Subtracting 4 Year in Date in Calendar
     */

    System.out.println("Date :"+ca1.get(Calendar.DATE));
    System.out.println("Month :"+ca1.get(Calendar.MONTH));
    System.out.println("Year :"+ca1.get(Calendar.YEAR));
    }
}

Output

Date :18

Month :6

Year :2009

JSP Calendar

admin — Sun, 17 May 2009 09:53:34 +0000

This JSP calendar can easily work with any java web application. This is free JSP calendar software for download and use. If you want to use calendar in your application you can use this calendar in JSP application. In this calendar, we can change year and month to go back and forward to option of calendar. Value of year and month in calendar can be changed by in combo box code.

<%@ page  language="java" import="java.util.*,java.text.*"%>
<%!
public int nullIntconv(String inv)
{   
    int conv=0;
        
    try{
        conv=Integer.parseInt(inv);
    }
    catch(Exception e)
    {}
    return conv;
}
%>
<%
 int iYear=nullIntconv(request.getParameter("iYear"));
 int iMonth=nullIntconv(request.getParameter("iMonth"));

 Calendar ca = new GregorianCalendar();
 int iTDay=ca.get(Calendar.DATE);
 int iTYear=ca.get(Calendar.YEAR);
 int iTMonth=ca.get(Calendar.MONTH);

 if(iYear==0)
 {
      iYear=iTYear;
      iMonth=iTMonth;
 }

 GregorianCalendar cal = new GregorianCalendar (iYear, iMonth, 1); 

 int days=cal.getActualMaximum(Calendar.DAY_OF_MONTH);
 int weekStartDay=cal.get(Calendar.DAY_OF_WEEK);
 
 cal = new GregorianCalendar (iYear, iMonth, days); 
 int iTotalweeks=cal.get(Calendar.WEEK_OF_MONTH);
  
%>
<html>
<head>
<title>How to create Calendar in JSPtitle>
<script>
function goTo()
{
  document.frm.submit()
}
script>
<style>
body
{
 font-family:Verdana, Arial, Helvetica, sans-serif
}
.dsb
{
 background-color:#EEEEEE
}
style>
head>

<body>
<form name="frm" method="post">
<table width="100%" border="0" cellspacing="0" cellpadding="0">
  <tr>
    <td width="25%">&nbsp;td>
    <td width="45%">&nbsp;td>
    <td width="30%">&nbsp;td>
  tr>
  <tr>
    <td>&nbsp;td>
    <td><table width="100%" border="0" cellspacing="0" cellpadding="0">
  <tr>
    <td><table width="100%" border="0" cellspacing="0" cellpadding="0">
      <tr>
        <td width="6%">Yeartd>
        <td width="7%">
        <select name="iYear" onChange="goTo()">
        <%
        // start year and end year in combo box to change year in calendar
        for(int iy=iTYear-70;iy<=iTYear+70;iy++)
        {
          if(iy==iYear)
          {
            %>
          <option value="<%=iy%>" selected="selected"><%=iy%>option>
          <%
          }
          else
          {
            %>
          <option value="<%=iy%>"><%=iy%>option>
          <%
          }
        }
       %>
        select>td>
        <td width="73%" align="center" style="color:#4E96DE"><h3><%=new SimpleDateFormat("MMMM").format(new Date(2008,iMonth,01))%> <%=iYear%>h3>td>
        <td width="6%">Monthtd>
        <td width="8%">
        <select name="iMonth" onChange="goTo()">
        <%
        // print month in combo box to change month in calendar
        for(int im=0;im<=11;im++)
        {
          if(im==iMonth)
          {
         %>
          <option value="<%=im%>" selected="selected"><%=new SimpleDateFormat("MMMM").format(new Date(2008,im,01))%>option>
          <%
          }
          else
          {
            %>
          <option value="<%=im%>"><%=new SimpleDateFormat("MMMM").format(new Date(2008,im,01))%>option>
          <%
          }
        }
       %>
        select>td>
      tr>
    table>td>
  tr>
  <tr>
    <td><table align="center" border="1" cellpadding="3" cellspacing="0" width="100%">
      <tbody>
        <tr>
          <th>Sunth>
          <th>Month>
          <th>Tueth>
          <th>Wedth>
          <th>Thuth>
          <th>Frith>
          <th>Satth>
        tr>
        <%
        int cnt =1;
        for(int i=1;i<=iTotalweeks;i++)
        {
        %>
        <tr>
          <% 
            for(int j=1;j<=7;j++)
            {
                if(cnt<weekStartDay || (cnt-weekStartDay+1)>days)
                {
                 %>
                <td align="center" height="35" class="dsb">&nbsp;td>
               <% 
                }
                else
                {
                 %>
                <td align="center" height="35" id="day_<%=(cnt-weekStartDay+1)%>"><span><%=(cnt-weekStartDay+1)%>span>td>
               <% 
                }
                cnt++;
              }
            %>
        tr>
        <% 
        }
        %>
      tbody>
    table>td>
  tr>
table>td>
    <td>&nbsp;td>
  tr>
  <tr>
    <td>&nbsp;td>
    <td>&nbsp;td>
    <td>&nbsp;td>
  tr>
table>
form>
body>
html>

Download source code JSP Calendar

JSP, Tomcat, JDBC, Projects, Example, Program » Calendar

Java Calendar – How to get Month Name

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Java Calendar – How to find Week of Year

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Java Calendar – How to find Week of Month

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Java Calendar – How to find Day of Year

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Java Calendar – How to find Day of Week

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Java Calendar – How to get Day of Week in Month

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Java Calendar – How to get day month year in date

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Java – How to find date difference

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JAVA – How to Add or Subtract Date

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JSP Calendar

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