Constructor and Generalization

--------------------------
Nama file: Karyawan.java
--------------------------

public class Karyawan {
    public String nik, nama, golongan;
    public int bulan;

    // constructor
    Karyawan(String nik, String nama, String golongan, int bulan){
        this.nik = nik;
        this.nama = nama;
        this.golongan = golongan;
        this.bulan = bulan;
    }

}

--------------------------
Nama file: KaryawanTetap.java
--------------------------

public class KaryawanTetap extends Karyawan{
    KaryawanTetap(String nik, String nama, String golongan, int bulan) {
        super(nik, nama, golongan, bulan);
    }

    public void infoPinjam(){
        int pinjaman = 0;

        if(this.golongan.equalsIgnoreCase("A")){
            pinjaman = 100000000;
        }else if(this.golongan.equalsIgnoreCase("B")){
            pinjaman = 75000000;
        }else if(this.golongan.equalsIgnoreCase("C")){
            pinjaman = 50000000;
        }

        double bunga = (double) pinjaman * 0.025;
        int jumlah = (pinjaman - (int)bunga);
        int perbulan = pinjaman / bulan;

        System.out.println("--- INFO PEMINJAM ---");
        System.out.println("NIK : \t\t"+ this.nik);
        System.out.println("Nama : \t\t"+ this.nama);
        System.out.println();
        System.out.println("--- DETIL PINJAMAN ---");
        System.out.println(String.format("Pinjaman: \tRp.%,2d", pinjaman));
        System.out.println(String.format("Bunga: \t\tRp.%,2d", (int)bunga));
        System.out.println("-----------------------------");
        System.out.println(String.format("Jumlah: \tRp.%,2d", jumlah));
        System.out.println("=============================");
        System.out.println(String.format("Bulanan: \tRp.%,2d", perbulan));
        System.out.println(String.format("Selama: \t%d bulan", bulan));
    }

}

--------------------------
Nama file: KaryawanHonorer.java
--------------------------

public class KaryawanHonorer extends Karyawan{

    KaryawanHonorer(String nik, String nama, String golongan, int bulan) {
        super(nik, nama, golongan, bulan);
    }

    public void infoPinjam(){
        int pinjaman = 0;

        if(this.golongan.equalsIgnoreCase("A")){
            pinjaman = 30000000;
        }else if(this.golongan.equalsIgnoreCase("B")){
            pinjaman = 20000000;
        }else if(this.golongan.equalsIgnoreCase("C")){
            pinjaman = 10000000;
        }

        double bunga = (double) pinjaman * 0.025;
        int jumlah = (pinjaman - (int)bunga);
        int perbulan = pinjaman / bulan;

        System.out.println("--- INFO PEMINJAM ---");
        System.out.println("NIK : \t\t"+ this.nik);
        System.out.println("Nama : \t\t"+ this.nama);
        System.out.println();
        System.out.println("--- DETIL PINJAMAN ---");
        System.out.println(String.format("Pinjaman: \tRp.%,2d", pinjaman));
        System.out.println(String.format("Bunga: \t\tRp.%,2d", (int)bunga));
        System.out.println("-----------------------------");
        System.out.println(String.format("Jumlah: \tRp.%,2d", jumlah));
        System.out.println("=============================");
        System.out.println(String.format("Bulanan: \tRp.%,2d ", perbulan));
        System.out.println(String.format("Selama: \t%d bulan", bulan));
    }

}

--------------------------
Nama file: Main.java
--------------------------

import java.util.Scanner;

public class Main {

    static Scanner sc = new Scanner(System.in);
    static int pilih = 0;

    public static void main(String[] args) {
        do {
            boolean valid = false;
            mainMenu();

            // memastikan user harus input integer
            while (!valid) {
                System.out.print("[ Ketik 1/2/3 ]: ");

                if (sc.hasNextInt()) {
                    pilih = sc.nextInt();

                    if(pilih > 3){
                        System.out.println("[ Menu salah!, Coba lagi. ]");
                        valid = false;
                    }else{
                        valid = true;
                    }
                } else {
                    System.out.println("[ Coba lagi! ]");
                    sc.next();
                    valid = false;
                }
            }

            // pilih 1 = karyawan tetap
            // pilih 2 = karyawan honorer
            mainInputKaryawan(pilih);

        } while (pilih != 3);
    }

    private static void mainInputKaryawan(int tipe) {
        String nik, nama, golongan;
        int bulan;

        sc.nextLine();
        System.out.print("NIK: ");
        nik = sc.nextLine();
        System.out.print("Nama: ");
        nama = sc.nextLine();

        //menu golongan
        System.out.print("Golongan [ A/B/C ]: ");
        golongan = sc.nextLine();

        System.out.print("Lama pinjaman (bln): ");
        bulan = sc.nextInt();

        if(tipe == 1){ // karyawan tetap
            KaryawanTetap k = new KaryawanTetap(nik, nama, golongan, bulan);
            k.infoPinjam();
        }else if(tipe == 2){ // karyawan honorer
            KaryawanHonorer k = new KaryawanHonorer(nik, nama, golongan, bulan);
            k.infoPinjam();
        }

        System.out.print("[ Tekan apapun untuk lanjut ]");
        sc.nextLine();
        sc.nextLine();
    }

    private static void mainMenu() {
        System.out.println("-----------------------");
        System.out.println("1. Karyawan Tetap");
        System.out.println("2. Karyawan Honorer");
        System.out.println("3. Keluar");
        System.out.println("-----------------------");
    }
}