Quan ly thu vien

package School;

import java.util.Scanner;

class TaiLieu {
    private String maTaiLieu, tenNhaXuatBan;
    private int soBanPhatHanh;
    Scanner scan = new Scanner(System.in);

    public void input() {
        System.out.print("Nhap ma tai lieu: ");
        maTaiLieu = scan.nextLine();
        System.out.print("Nhap ten nha xuat ban: ");
        tenNhaXuatBan = scan.nextLine();
        System.out.print("Nhap so ban phat hanh: ");
        soBanPhatHanh = Integer.parseInt(scan.nextLine());
    }

    public void ouputTitle() {
        System.out.printf("%-20s %-20s %-20s %-20s %-20s %-20s %-20s %-20s\n",
                "Ma Tai Lieu", "Nha Xuat Ban", "So Ban Phat Hanh",
                "Tac Gia Sach", "So Trang Sach", "So Phat Hanh",
                "Thang Phat Hanh", "Ngay Phat Hanh");
    }

    public void output() {
        System.out.printf("%-20s %-20s %-20d", maTaiLieu, tenNhaXuatBan,
                soBanPhatHanh);
    }
}

class Sach extends TaiLieu {
    private String tenTacGia;
    private int soTrang;

    public String getTenTacGia() {
        return tenTacGia;
    }

    public void setTenTacGia(String tenTacGia) {
        this.tenTacGia = tenTacGia;
    }

    public int getSoTrang() {
        return soTrang;
    }

    public void setSoTrang(int soTrang) {
        this.soTrang = soTrang;
    }

    @Override
    public void input() {
        Scanner scan = new Scanner(System.in);
        super.input();
        System.out.print("Nhap ten tac gia cuon sach: ");
        tenTacGia = scan.nextLine();
        System.out.print("Nhap so trang cuon sach: ");
        soTrang = Integer.parseInt(scan.nextLine());
    }

    public void output() {
        super.output();
        System.out.printf("%-20s %-20d %-20s %-20s %-20s\n", tenTacGia,
                soTrang, " ", " ", " ");
    }
}

class TapChi extends TaiLieu {
    private int soPhatHanh;
    private int thangPhatHanh;

    public int getSoPhatHanh() {
        return soPhatHanh;
    }

    public void setSoPhatHanh(int soPhatHanh) {
        this.soPhatHanh = soPhatHanh;
    }

    public int getThangPhatHanh() {
        return thangPhatHanh;
    }

    public void setThangPhatHanh(int thangPhatHanh) {
        this.thangPhatHanh = thangPhatHanh;
    }

    @Override
    public void input() {
        Scanner scan = new Scanner(System.in);
        super.input();
        System.out.print("Nhap so phat hanh: ");
        soPhatHanh = Integer.parseInt(scan.nextLine());
        System.out.print("Nhap thang phat hanh: ");
        thangPhatHanh = Integer.parseInt(scan.nextLine());
    }

    public void output() {
        super.output();
        System.out.printf("%-20s %-20s %-20s %-20d %-20s\n", " ", " ",
                soPhatHanh, thangPhatHanh, " ");
    }
}

class Bao extends TaiLieu {
    private int ngayPhatHanh;

    public int getNgayPhatHanh() {
        return ngayPhatHanh;
    }

    public void setNgayPhatHanh(int ngayPhatHanh) {
        this.ngayPhatHanh = ngayPhatHanh;
    }

    @Override
    public void input() {
        Scanner scan = new Scanner(System.in);
        super.input();
        System.out.print("Nhap ngay phat hanh: ");
        ngayPhatHanh = Integer.parseInt(scan.nextLine());
    }

    public void output() {
        super.output();
        System.out.printf("%-20s %-20s %-20s %-20d %-20s\n", " ", " ", " ",
                ngayPhatHanh, " ");
    }
}

public class QuanLyThuVien {
    int n;
    TaiLieu taiLieu[];

    public void input() {
        Scanner scan = new Scanner(System.in);
        System.out.print("Nhap so tai lieu: ");
        n = Integer.parseInt(scan.nextLine());
        taiLieu = new TaiLieu[n];

        for (int i = 0; i < n; i++) {
            System.out.print("Nhap loai tai lieu: (sach, tapchi, bao) ");
            String loai = scan.nextLine();
            if (loai.equals("sach"))
                taiLieu[i] = new Sach();
            else if (loai.equals("tapchi"))
                taiLieu[i] = new TapChi();
            else if (loai.equals("bao"))
                taiLieu[i] = new Bao();
            else {
                --i;
                continue;
            }
            taiLieu[i].input();
        }
        scan.close();
    }

    public void output() {
        taiLieu[0].ouputTitle();
        for (int i = 0; i < n; i++) {
            taiLieu[i].output();

        }
    }

    // Neu muon lay du lieu tu cac lop con
    public void outputTenTacGia() {
        for (int i = 0; i < n; i++) {
            if (taiLieu[i] instanceof Sach)
                System.out.println("Tac gia cuon sach thu " + (i + 1)
                        + " la : " + ((Sach) taiLieu[i]).getTenTacGia());
        }
    }

    public static void main(String[] args) {
        QuanLyThuVien ql = new QuanLyThuVien();
        ql.input();
        ql.output();
        ql.outputTenTacGia();
    }
}