Cartesian Product Exemple

public static void main(String[] args) {
        
    cartesianProduct ( Arrays.asList (
                         Arrays.asList( 1900, 1901, 1902 ) ,
                         Arrays.asList( Arrays.asList("R","Y") , Arrays.asList("RR","YY") ) ,
                         Arrays.asList(Arrays.asList("10") )
                     )
    ) ;
} ;
    
public static <T> void cartesianProduct ( List<List<T>> lists ) {
        
        int solutions = 1 ;
        for(int i = 0; i < lists.size(); i++ ) solutions *= lists.get(i).size() ;
        System.out.println(" Total combination : " + solutions  + "\n " ) ;
        for(int i = 0; i < solutions; i++) {
            int j = 1 ;
            List<T> combined = new ArrayList<>();
            for( List<T> list : lists) {
                if( list.get((i/j) % list.size() ) instanceof List) {
                  combined.addAll( (List) list.get( (i/j) % list.size() ) ) ;
                }
                else {
                    combined.add( list.get( (i/j) % list.size() ) ) ;
                }
                j *= list.size() ;
            }
            System.out.println(combined) ;
            System.out.println() ;
        }