i need help with some code modification
This is a book class
Code:
  // The fields.
    private String author;
    private String title;
    private int pages;
    private String refNumber;
    private int borrowed;
constructors and some methods omitted

basically the integer field borrowed is meant to keep a count of the number of times has been borrowed, what i need help with is adding a mutator borrow, and this should update the field by 1 each time it is called, include an accessor getBorrowed, that returns a value of this new field as its result.


The main code is below it self, if anyone has time to look at it please help,


and this runs in a normal jdk environment but we use an interface called blue j to view things(as a terminal window)
Code:
/**
  * @author (Aisha Aliyu)
  * @version (28/10/2003)
  */
class Book
{
    // The fields.
    private String author;
    private String title;
    private int pages;
    private String refNumber;
    private int borrowed;

    /**
     * Set the author and title fields when this object
     * is constructed.
     */
    public Book(String bookAuthor, String bookTitle, int bookPages, String ref, int borrow)
    {
        author = bookAuthor;
        title = bookTitle;
        pages = bookPages;
        refNumber = ref;
        borrowed = borrow;

    }

   // The number of pages. 
    public int getPages()
    {
    return pages;
    }

    // return the refrence number of the book
    public String getRefNumber()
    {
        return refNumber;
    }

  // Simulate the printing of the author's name.
   public void printAuthor()
    {
     System.out.println("*Book Author*= " + author); 
    }

  // Simulate the printing of the book's title.  
   public void printTitle()
   {
     System.out.println("*Book Title* = " + title);
   }

  // Simulate the printing of the book details.
   public void printDetails()
{
       if(refNumber == "") {
    System.out.println("*Book Author*      = " + author);
    System.out.println("*Book Title*       = " + title);
    System.out.println("*Pages*            = " + pages);
    System.out.println("*Reference Number* = " + refNumber); 
}
    else {

        System.out.println("*Reference Number* = zzz");
    }
}

  // The refrence mutator.
    public void setRefNumber(String ref)
   {
   if(ref.length() < 3) {
            System.out.println("The reference number must be at least 3 characters");
       }
       else {
       refNumber = ref;
       }
}

// The Borrowed mutator.
public int borrowed()
{
return borrowed;
}
}
[ArchAngel added CODE tags]