School Library [Java]

import java.util.*;

public class SchoolLibrary {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String[] input = scanner.nextLine().split("&");

        List<String> shelfWithBooks = new ArrayList<>(Arrays.asList(input));

        String command;

        while (!"Done".equals(command = scanner.nextLine())) {
            String[] tokens = command.split(" \\| ");

            if ("Add Book".equals(tokens[0])) {
                String bookName = tokens[1];

                if (shelfWithBooks.contains(bookName)) {
                    continue;
                } else {
                    shelfWithBooks.add(0, bookName);
                }
            }

            if ("Take Book".equals(tokens[0])) {
                String bookName = tokens[1];

                if (!shelfWithBooks.contains(bookName)) {
                    continue;
                } else {
                    shelfWithBooks.remove(bookName);
                }
            }

            if ("Swap Books".equals(tokens[0])) {
                String firstBook = tokens[1];
                String secondBook = tokens[2];
                int indexOfTheFirstBook = shelfWithBooks.indexOf(tokens[1]);
                int indexOfTheSecondBook = shelfWithBooks.indexOf(tokens[2]);

                if (shelfWithBooks.contains(firstBook) && shelfWithBooks.contains(secondBook)) {
                    Collections.swap(shelfWithBooks, indexOfTheFirstBook, indexOfTheSecondBook);
                }
            }

            if ("Insert Book".equals(tokens[0])) {
                String bookName = tokens[1];
                shelfWithBooks.add(bookName);
            }

            if ("Check Book".equals(tokens[0])) {
                int index = Integer.parseInt(tokens[1]);

                if (index < 0 || index > shelfWithBooks.size()) {
                    continue;
                } else {
                    String bookName = shelfWithBooks.get(index);
                    System.out.println(bookName);
                }
            }
        }

        String completedBookshelf = String.join(", ", shelfWithBooks);
        System.out.println(completedBookshelf);
    }
}