mutators

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,
:confused:

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]

What problem are you having? How do you think it should be done?

You aren't by any chance using the book Fundamentals of Java by Martin Osborne, are you?