Java Month Get getMonthCount(String from, String to)

Description

get Month Count

License

Open Source License

Declaration

public static int getMonthCount(String from, String to) throws Exception 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.text.ParseException;
import java.text.SimpleDateFormat;

import java.util.Date;

import java.util.Locale;

public class Main {
    private static final SimpleDateFormat FORMAT = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    private static final SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("yyyy-MM-dd");

    public static int getMonthCount(String from, String to) throws Exception {
        return getMonthCount(from, to, DATE_FORMAT.toPattern());
    }/*w  ww . j  a va2 s . c o m*/

    public static int getMonthCount(String from, String to, String format) throws Exception {
        Date fromDate = dateFormatCheck(from, format);
        Date toDate = dateFormatCheck(to, format);

        // if two date are same, return 0.
        if (fromDate.compareTo(toDate) == 0)
            return 0;

        SimpleDateFormat yearFormat = new java.text.SimpleDateFormat("yyyy", java.util.Locale.KOREA);
        SimpleDateFormat monthFormat = new java.text.SimpleDateFormat("MM", java.util.Locale.KOREA);

        int fromYear = Integer.parseInt(yearFormat.format(fromDate));
        int toYear = Integer.parseInt(yearFormat.format(toDate));
        int fromMonth = Integer.parseInt(monthFormat.format(fromDate));
        int toMonth = Integer.parseInt(monthFormat.format(toDate));

        int result = 0;
        result += ((toYear - fromYear) * 12);
        result += (toMonth - fromMonth);

        return result;
    }

    public static Date dateFormatCheck(String source, String format) throws ParseException {

        if (source == null) {
            throw new ParseException("date string to check is null", 0);
        }

        if (format == null) {
            throw new ParseException("format string to check date is null", 0);
        }

        SimpleDateFormat formatter = new SimpleDateFormat(format, Locale.KOREA);

        Date date = null;

        try {
            date = formatter.parse(source);
        } catch (ParseException e) {
            throw new ParseException(" wrong date:\"" + source + "\" with format \"" + format + "\"", 0);
        }

        if (!formatter.format(date).equals(source)) {
            throw new ParseException("Out of bound date:\"" + source + "\" with format \"" + format + "\"", 0);
        }

        return date;
    }

    public static String format(Date date) {
        return FORMAT.format(date);
    }

    public static Date parse(String datetime) {
        try {
            return FORMAT.parse(datetime);
        } catch (ParseException e) {
            return new Date();
        }
    }
}

Related

1. getMonthAndDate()
2. getMonthBefore(Date d, int number)
3. getMonthBegin(String strdate)
4. getMonthBegin(String strdate)
5. getMonthByNow(int month)
6. getMonthDesc(Date month)
7. getMonthEnd(Date date)
8. getMonthEnd(String strdate)
9. getMonthEnd(String strdate)