[JAVA] 날짜 비교

SimpleDateFormat을 이용한 날짜 비교하는 방법에 대해 알아보겠습니다.

소스코드

import java.text.SimpleDateFormat;
import java.util.Date;

public class SimpleDateFormatExample {

    public static long getDayCount( String start, String end ) {
        SimpleDateFormat format = new SimpleDateFormat( "yyyy-M-d" );

        long diff = -1;

        try {
            Date dateStart = format.parse( start );
            Date dateEnd = format.parse( end );

            // time is always 00:00:00 so rounding should help to ignore the
            // missing hour when going from winter to summer time as well as the
            // extra hour in the other direction
            diff = Math.round( ( dateEnd.getTime() - dateStart.getTime() ) / (double)( 60 * 60 * 24 * 1000 ) );
        }
        catch ( Exception e ) {
            e.printStackTrace();
        }

        return diff;
    }

    public static void main( String[] args ) {
        long diff = getDayCount( "2021-1-1", "2021-4-26" );
        System.out.println( "결과 : " + diff + " 일" );
    }
}

결과

결과 : 115 일