java code problem

[peterx peter]

hi!
1-I try to put 5 diffent books in my library object but toString() method dose not work if I write like this: bok[].gettitle() but what do I put in the bok array (bok[?]).
2- How do I test the program?

  
   class Book{

privateString title;
        privateString author;
private String isbn;
 
    public Book(String title, String author, String isbn)
   { 
      this.title=title;
      this.author=author;
      this.isbn=isbn;
 
   }
   
    public String gettitle()
   {
     return title;
   } 
    public String getauthor()
   {
       return author;
   }  
    public String getIsbn()
   {
       return isbn;
   } 
}
//------------------
 class Library{

  private Book[] bok;
  private int numberOfBook;      
  
  public Library(int size)
 {
   bok = new Book[size];    
   numberOfBook=0;
 
     }
        
     public void addBook(Book b)
    {     
      if ( numberOfBook < bok.length)
     {    
         bok[numberOfBook] = b;     
         numberOfBook += 1; 
     
           } else {   
         System.out.println("Catalogue is already full. "     
                       + "Unable to add new book."); 
         }
      } 
      
       public int size()
      {
        return numberOfBook;
      
      }
     
      public String toString()
   {
      return "numberOfBooks: "+numberOfBook+" title: "+bok.gettitle()+"author: "
      +bok.getauthor()+"isbn: "+bok.getIsbn();
   }  
}
 
 public static void main(String[]atgs)
 {
 
Library bibliotek = new Library(5); // Max 100 b�cker kan lagras
library.addBook(new Bok("book1", "Tom", "5452222"));
library.addBook(new Bok("book2", "De", "02220142"));
library.addBook(new Bok("book3", "Gr", "922227175"));
library.addBook(new Bok("book4", "En", "22223463"));
library.addBook(new Bok("book5", "Enl", "222963"));
 

[Ta Ri Ki Sun]

1. Your toString method should loop through all the books it has to get the information about book[0] through to the end.

2. What would you like to test? Your code has problems such as that Book[] never being initialised but essentially that main method at the end is creating a library and adding 5 books, to test further you can add the method getBook(int index OR String isbn etc).

[John Bartlett]

Problem you got is that you need to loop through your array of books.

Also why are you using arrays for such a thing as this, wouldnt it be better to have a dynamic list like an ArrayList? This would mean you would not have to specifiy a size you could jsut add as many books as you like.

O btw dont really think this is an Intermediate question?

John