question: public static Date convertDate ( Value value , Calendar calendar ) { if ( value == ValueNull . INSTANCE ) { return null ; } ValueDate d = ( ValueDate ) value . convertTo ( Value . DATE ) ; Calendar cal = ( Calendar ) calendar . clone ( ) ; cal . clear ( ) ; cal . setLenient ( true ) ; long dateValue = d . getDateValue ( ) ; setCalendarFields ( cal , yearFromDateValue ( dateValue ) , monthFromDateValue ( dateValue ) , dayFromDateValue ( dateValue ) , 0 , 0 , 0 , 0 ) ; long ms = cal . getTimeInMillis ( ) ; return new Date ( ms ) ; }
target:  Convert the date to the specified time zone.