[JAVA]How can I add here this array code?

Question

I'd like to print out that I can't find the books that are not in the array, although I want just one sentence "no data".

Please give me some advice.

Answer 1

You can add a boolean that gets updated once the book is found, and once you are done from the loop, it will print 'no data' if the book wasn't found, something like this:

 public static void main(String[] args)
    {
        Book[] book = {new Book("java", 150, 2016), new Book("python", 100, 2019), new Book("javascript", 200, 2018)};
        Scanner in = new Scanner(System.in);
        System.out.print("insert book title >> ");
        String title = in.nextLine();
        boolean found = false;

        for (Book b : book)
        {
            if (title.equals(b.getTitle()))
            {
                System.out.println(b.toString());
                found = true;
                break;
            }
        }
       if (!found) System.out.println("no data");
    }

Answer 2

You could do it java 8 way as well:

public static void main(String[] args) {
    Book[] book = {new Book("java", 150, 2016), new Book("python", 100, 2019), new Book("javascript", 200, 2018)};
    Scanner in = new Scanner(System.in);
    System.out.print("insert book title >> ");
    String title = in.nextLine();
    Book b = Arrays.stream(book).filter(book1 -> book1.getTitle().equals(title)).findAny().orElse(null);
    if (null == b) {
        System.out.println("no data");
    } else {
        System.out.println(b);
    }
}

Answer 3

I'd like to print out that I can't find the books that are not in the array, although I want just one sentence "no data".

Please give me some advice.