book.java

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/**
 * This class models a book. It extends {@link CatalogItem} and
 * adds the following information:
 * <ol>
 * <li>the author of the book, a <code>String</code></li>
 * <li>the number of pages in the book, an <code>int</code></li>
 * </ol>
 *
 * @author author name
 * @version  1.0.0
 * @see CatalogItem
 */
public class Book extends CatalogItem  {

    /* Author of the book.*/
    private String  author;

    /* Number of pages in the book.*/
    private int  numberOfPages;

    /**
     * Constructs a <code>Book</code> object.
     *
     * @param initialCode  the code of the book.
     * @param initialTitle  the title of the book.
     * @param initialYear  the year the book was published.
     * @param initialAuthor  the author of the book.
     * @param initialNumberOfPages  the number of pages in the book.
     */
    public Book(String initialCode, String initialTitle,
                int initialYear, String initialAuthor,
                int initialNumberOfPages) {

        super(initialCode, initialTitle, initialYear);//In Java, the super call in constructors must always be the first statement.

        author = initialAuthor;
        numberOfPages = initialNumberOfPages;
    }

    /**
     * Returns the author of this book.
     *
     * @return  the author of this book.
     */
    public String  getAuthor()  {

        return  author;
    }

    /**
     * Returns the number of pages in this book.
     *
     * @return  the number of pages in this book.
     */
    public int  getNumberOfPages()  {

        return  numberOfPages;
    }

    /**
     * Returns the string representation of this book.
     *
     * @return  the string representation of this book.
     */
    public String toString()  {

        return  super.toString() + "_" + getAuthor() + "_"
                + getNumberOfPages();
    }
}