Java Day in Month getNumberOfDaysInMonth(Integer year, Integer month)

Description

get Number Of Days In Month

License

Apache License

Declaration

public static Integer getNumberOfDaysInMonth(Integer year, Integer month) 

Method Source Code

//package com.java2s;
/*/*w  w w .  j av a2  s. co m*/
 * Copyright 2013 Cyber Eagle
 *
 *    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.
 */

public class Main {
    public static Integer getNumberOfDaysInMonth(Integer year, Integer month) {
        Integer result = null;
        if (year != null && month != null) {
            if (month == 1) {
                result = 31;
            } else if (month == 2) {
                result = isLeapYear(year) ? 29 : 28;
            } else if (month == 3) {
                result = 31;
            } else if (month == 4) {
                result = 30;
            } else if (month == 5) {
                result = 31;
            } else if (month == 6) {
                result = 30;
            } else if (month == 7) {
                result = 31;
            } else if (month == 8) {
                result = 31;
            } else if (month == 9) {
                result = 30;
            } else if (month == 10) {
                result = 31;
            } else if (month == 11) {
                result = 30;
            } else if (month == 12) {
                result = 31;
            } else {
                throw new AssertionError("Month is out of range 1..12:" + month);
            }
        }
        return result;
    }

    public static boolean isLeapYear(Integer year) {
        boolean result = false;
        if (year % 100 == 0) {
            // this is a century year
            if (year % 400 == 0) {
                result = true;
            }
        } else if (year % 4 == 0) {
            result = true;
        }
        return result;
    }
}

Related

1. getMonthDays(int year, int month)
2. getMonthDaysArray(int year)
3. getMonthDayString(long l, boolean timezone, boolean formated)
4. getMonthlyCronExpression(int minutes, int hours, int dayOfMonth)
5. getMonthOfDayMark(int day)
6. getNumberOfDaysInMonthes(int theyear)
7. getNumDaysInMonth(String monthID, String yearID)
8. getPreMonthDayStr(String curday)
9. getStartMonthDayOfDate(String yyyyMM)