perhitungan nilai matakuliah menggunakan java

Simpan file dengan nama lat......
perhitungan nilai matakuliah menggunakan java....
tugas 10%
quiz 20%
uts 30%
uas 40%

import java.util.Scanner;
import javax.swing.*;
public class lat {
    public static void main (String[] args)
        {
            Scanner in = new Scanner (System.in);
            String nama, nim, kelas, matakuliah;
            int tugas, quiz, uts, uas;

            System.out.print("Nama : ");
            nama = in.nextLine();
            System.out.print("Nim : ");
            nim = in.nextLine();
            System.out.print("Kelas : ");
            kelas = in.nextLine();
            System.out.print("Matakuliah : ");
            matakuliah = in.nextLine();

            System.out.print("Nilai Tugas : ");
            tugas = in.nextInt();
            System.out.print("Nilai Quiz : ");
            quiz = in.nextInt();
            System.out.print("Nilai UTS : ");
            uts = in.nextInt();
            System.out.print("Nilai UAS : ");
            uas = in.nextInt();

            System.out.println("----------------------------------------");
            System.out.println("Nama                : "+nama);
            System.out.println("NIM              : "+nim);
            System.out.println("Kelas              : "+kelas);
            System.out.println("Matakuliah          : "+matakuliah);


            double nilai;
            nilai = (0.1*tugas)+(0.2*quiz)+(0.3*uts)+(0.4*uas);

            if((nilai<=100)&(nilai>=80))
            System.out.println("Hasil akhir      : "+nilai+" Grade : A");

            else
                if((nilai<=79)&(nilai>=67))
                    System.out.println("Hasil akhir      : "+nilai+" Grade : B");

                    else
                        if((nilai<=66)&(nilai>=50))
                            System.out.println("Hasil akhir      : "+nilai+" Grade : C");

                            else
                                System.out.println("Hasil akhir      : "+nilai+" Grade : D");

        System.out.println("-----------------------------------------");

}
}