날짜 양력 <-> 음력 상호변환.

라이브러리: icu4j 다운로드 : http://site.icu-project.org/download/48#ICU4J-Download
icu4j-4_8_1_1.jar

 
package com.tistory.yysvip.calendar;
 import java.util.Calendar;
 import org.apache.log4j.Logger;
 import com.ibm.icu.util.ChineseCalendar;
 
/**
 * 
 * com.tistory.petulantman.calendar
 *    |_ LunarCalendar.java
 *
 * 
 * @date : 2012. 4. 25. 오전 9:52:35
 * @version :
 * @author : 까칠한쑤
 */
public class LunarCalendar {
 
        private Logger log = Logger.getLogger(this.getClass());
 
        private Calendar cal ;
        private ChineseCalendar cc ;
 
 
        public LunarCalendar() {
                // default TimeZone, Locale 을 사용..
                cal = Calendar.getInstance() ;
                cc = new ChineseCalendar();
        }
 
        /**
         * 
         
         * 1. 개요 : 양력(yyyyMMdd) -> 음력(yyyyMMdd)
         * 2. 처리내용 : 양력을 음력으로 변환처리한다.
         * 
         * @Method Name : toLunar
         * @date : 2012. 4. 25.
         * @author : 까칠한쑤
         * @history :
         *      -----------------------------------------------------------------------
         *      변경일                          작성자                                          변경내용
         *      ----------- ------------------- ---------------------------------------
         *      2012. 4. 25.            까칠한쑤                                최초 작성
         *      -----------------------------------------------------------------------
         *
         * @param yyyymmdd
         * @return
         */
        public synchronized String toLunar( String yyyymmdd ) {
                if(    yyyymmdd == null )
                        return "" ;
 
                String date = yyyymmdd.trim() ;
                if( date.length() != 8 ) {
                        if( date.length() == 4 )
                                date = date + "0101" ;
                        else if( date.length() == 6 )
                                date = date + "01" ;
                        else if( date.length() > 8 )
                                date = date.substring(0,8) ;
                        else
                                return "" ;
                }
 
                cal.set( Calendar.YEAR, Integer.parseInt(date.substring(0,4)) ) ;
                cal.set( Calendar.MONTH, Integer.parseInt(date.substring(4,6))-1 ) ;
                cal.set( Calendar.DAY_OF_MONTH, Integer.parseInt(date.substring(6)) ) ;
 
                cc.setTimeInMillis( cal.getTimeInMillis() ) ;
 
                // ChinessCalendar.YEAR 는 1~60 까지의 값만 가지고 ,
 
                // ChinessCalendar.EXTENDED_YEAR 는 Calendar.YEAR 값과 2637 만큼의 차이를 가집니다.
                int y = cc.get(ChineseCalendar.EXTENDED_YEAR)-2637 ;
                int m = cc.get(ChineseCalendar.MONTH)+1 ;
                int d = cc.get(ChineseCalendar.DAY_OF_MONTH) ;
 
                StringBuffer ret = new StringBuffer() ;
                if( y < 1000 )          ret.append( "0" ) ;
                else if( y < 100 )      ret.append( "00" ) ;
                else if( y < 10 )       ret.append( "000" ) ;
                ret.append( y ) ;
 
                if( m < 10 ) ret.append( "0" ) ;
                ret.append( m ) ;
 
                if( d < 10 ) ret.append( "0" ) ;
                ret.append( d ) ;
 
                return ret.toString() ;
        }
 
        /**
         * 
         
         * 1. 개요 : 음력(yyyyMMdd) -> 양력(yyyyMMdd)
         * 2. 처리내용 : 음력을 양력으로 변환처리한다.
         * 
         * @Method Name : fromLunar
         * @date : 2012. 4. 25.
         * @author : 까칠한쑤
         * @history :
         *      -----------------------------------------------------------------------
         *      변경일                          작성자                                          변경내용
         *      ----------- ------------------- ---------------------------------------
         *      2012. 4. 25.            까칠한쑤                                최초 작성
         *      -----------------------------------------------------------------------
         *
         * @param yyyymmdd
         * @return
         */
        public synchronized String fromLunar( String yyyymmdd )
        {
                if (yyyymmdd == null ) return "" ;
 
                String date = yyyymmdd.trim() ;
 
                if( date.length() != 8 ) {
                        if( date.length() == 4 )
                                date = date + "0101" ;
                        else if( date.length() == 6 )
                                date = date + "01" ;
                        else if( date.length() > 8 )
                                date = date.substring(0,8) ;
                        else
                                return "" ;
                }
 
                cc.set( ChineseCalendar.EXTENDED_YEAR, Integer.parseInt(date.substring(0,4))+2637 ) ;
                cc.set( ChineseCalendar.MONTH, Integer.parseInt(date.substring(4,6))-1 ) ;
                cc.set( ChineseCalendar.DAY_OF_MONTH, Integer.parseInt(date.substring(6)) ) ;
 
                cal.setTimeInMillis( cc.getTimeInMillis() ) ;
 
                int y = cal.get(Calendar.YEAR) ;
                int m = cal.get(Calendar.MONTH)+1 ;
                int d = cal.get(Calendar.DAY_OF_MONTH) ;
 
                StringBuffer ret = new StringBuffer() ;
                if( y < 1000 )          ret.append( "0" ) ;
                else if( y < 100 )      ret.append( "00" ) ;
                else if( y < 10 )       ret.append( "000" ) ;
                ret.append( y ) ;
 
                if( m < 10 ) ret.append( "0" );
                ret.append( m ) ;
 
                if( d < 10 ) ret.append( "0" );
                ret.append( d ) ;
 
                return ret.toString() ;
        }
 
        public static void main(String args[])
        {
                LunarCalendar lc = new LunarCalendar() ;
 
                System.out.println("2012년 4월 25일에 대한 음력날짜는 아래와 같습니다.");
                System.out.println( lc.toLunar("20120425") ) ; // 양력을 음력으로 바꾸기
 
                System.out.println("2012년 4월 05일에 대한 양력날짜는 아래와 같습니다.");
                System.out.println( lc.fromLunar("20120405") ) ; // 2012년 4월 25일에 대한 음력날짜를 집어넣는다.
        } // end class
}

출처 : http://yysvip.tistory.com/159