Java Day of Month getLastDayInMonth(int year, int month)

Description

get Last Day In Month

License

Apache License

Declaration

public static int getLastDayInMonth(int year, int month) 

Method Source Code

//package com.java2s;
/**/*from   w  w  w  .ja  v  a 2 s.com*/
Copyright 2014 Jens Glufke
    
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
    
http://www.apache.org/licenses/LICENSE-2.0
    
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
 * -----------------------------------------------------------------------
 *
 */

import java.util.Calendar;

import java.util.HashMap;

public class Main {
    /**
     * key   - year
     * value - day count
     */
    private static HashMap<Integer, Integer> daysOfFebruary = new HashMap<Integer, Integer>();

    public static int getLastDayInMonth(int year, int month) {

        int lLastDay = -1;
        switch (month) {
        case 0: // Jan
        case 2: // Mar
        case 4: // May
        case 6: // Jul
        case 7: // Aug
        case 9: // Oct
        case 11: // Dec
            lLastDay = 31;
            break;
        case 1: // Feb   
            Integer lDayCount = daysOfFebruary.get(year);
            if (lDayCount == null) {
                Calendar lCalendar = Calendar.getInstance();
                lCalendar.set(year, 2, 1);
                lCalendar.add(Calendar.DATE, -1);
                lDayCount = lCalendar.get(Calendar.DAY_OF_MONTH);
                daysOfFebruary.put(year, lDayCount);
            }
            lLastDay = lDayCount;
            break;
        case 3: // Apr
        case 5: // Jun
        case 8: // Sep
        case 10: // Nov
            lLastDay = 30;
            break;
        default:
            throw new IllegalArgumentException("month out of range:" + month);
        }
        return lLastDay;
    }
}

Related

1. getFistDayOfMonth(Date date)
2. getFromDate(boolean invoiceSearchFromFirstDayOfMonth)
3. getLastDateOfCurMonth()
4. getLastDay(int year, int month)
5. getLastDayByMonthWeek(int year, int month, int week)
6. getLastDayOfCurMonth()
7. getLastDayOfLastMonth()
8. getLastDayOfMonth()
9. getLastdayofMonth()