Add accessor and mutator methods to the Book class created in question #13.

Question

What will be an ideal response?

Answer 1

```
/** Class for a book with title, author, ISBN and year published.
Class invariant: A Book always has a title and author.
*/
public class Book
{
/** Instance variables */
private String title;
private String author;
private String ISBN;
private int yearPublished;

/** Accessor methods */
public String getTitle()
{
return title;
}
public String getAuthor()
{
return author;
}
public String getISBN()
{
return ISBN;
}
public int getYearPublished()
{
return yearPublished;
}
/** Mutator methods */
public void setISBN(String isbn)
{
ISBN = isbn;
}
public void setYearPublished(int y)
{
yearPublished = y;
}
/** Facilitator methods */
public String toString()
{
return (title + " " + author + " " + ISBN + " " + yearPublished);
}
public boolean equals(Book otherBook)
{
if(otherBook == null)
return false;
else
return (title.equals(otherBook.title) &&
author.equals(otherBook.author)
&& ISBN.equals(otherBook.ISBN) &&
yearPublished == otherBook.yearPublished);
}
}

```