/*
 * Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
 * Date: 2022-04-25
 * Description: This is the Lender class.
 */

public class Lender extends User {
	/**
	 * Constructor.
	 *
	 * @param name The user's name.
	 * @param book number of bookds lent by the user. This will be store in negetive value.
	 */
	public Lender(String name, int book) {
		// lender negetive book value
		super(name, -book);
	}

	/**
	 * Increases the number of bookds.
	 *
	 * @param book the number of books.
	 */
	public void moreBook(int book) {
		setBook(getBook() - book);
	}

	/**
	 * Test.
	 */
	public static void testLender() {
		Lender l = new Lender("Anna", 5);
		System.out.println(l.getName() == "Anna");
		System.out.println(l.getBook() == -5);
		l.setBook(-6);
		System.out.println(l.getBook() == -6);
		l.moreBook(2);
		System.out.println(l.getBook() == -8);
		l.moreBook(-9);
		System.out.println(l.getBook() == 1);
	}
}