You can try something like this:
Collection<Integer> id = Arrays.asList(2316, 2317, 2318);
Collection<Integer> existingId = Arrays.asList(1004, 1762, 1892, 1342, 1942, 2316);
Collection<Integer> similar = new HashSet<Integer>( id );
similar.removeAll( existingId );
System.out.println("Different:"+similar);
System.out.println("#of items that are differnt:"+similar.size());
1
solved How to compare List of Long and return the number of matches [closed]