Thread: Finding String in ArrayList

I am having some trouble searching an ArrayList to see if it contains a string.

public Book findByTitle(String title){
 
	    Book book = new Book();
 
	    int location;
		if(books.contains(title)){
		 location = books.indexOf(title);
		 book = books.get(location);
		 		}
		else{
			return null;
		}
		    return book;
			}

I am told to search for a book by its title, if it is found return the Book otherwise return null. This method is called from

   private void findBook(Library lib) {
      Scanner scn = new Scanner(System.in);
      String title;
      Book book;
 
      System.out.print("Title: ");
      title = scn.nextLine();
 
      book = lib.findByTitle(title);
 
      System.out.println("ISBN: " + book.getIsbn());
      System.out.println("Title: " + book.getTitle());
      System.out.println("Author: " + book.getAuthor());
      System.out.println("RRP: " + book.getRrp());
   }

However I get a null pointer exception

Thank you for any help

books.contains(title)

'title' is a String object. Look at the API doc for ArrayList.contains(Object) - it explains why your code isn't working.

I assume and Object is something that would be in another Array? such as Book is an object?

What do I use to see if the array contains a String then?

Thank you for your help