PBO-A Database Kuliah

pada kesempatan kali ini saya mendapat tugas membuat database kuliah
Berikut adalah source codenya:
1. Dosen

 public class dosen extends objek  
 {  
   private int gaji;  
   private String jabatan;  
   public dosen (String name, int kode, int Gaji, String Jabatan)  
   {  
     super(name, kode);  
     gaji = Gaji;  
     jabatan = Jabatan;  
   }  
   public int getgaji()  
   {  
     return gaji;  
   }  
   public String getjabatan()  
   {  
     return jabatan;  
   }  
   public void print(){  
     System.out.println("Nama  : "+this.getnama());  
     System.out.println("Kode  : "+this.getid());  
     System.out.println("Gaji  : "+this.getgaji());  
     System.out.println("Jabatan : "+this.getjabatan());  
   }  
 }  

2. Database

 import java.util.ArrayList;  
 public class database  
 {  
   private ArrayList<pegawai> pgw;  
   private ArrayList<dosen> dsn;  
   private ArrayList<mahasiswa> mhs;  
   private ArrayList<kelas> kls;  
   private ArrayList<matkul> mk;  
   private ArrayList<buku> buku;  
   public database(){  
     pgw= new ArrayList<pegawai>();  
     dsn= new ArrayList<dosen>();  
     mhs= new ArrayList<mahasiswa>();  
     kls= new ArrayList<kelas>();  
     mk= new ArrayList<matkul>();  
     buku= new ArrayList<buku>();  
   }  
   public void addpgw (pegawai the_pgw){  
     pgw.add(the_pgw);  
   }  
   public void adddsn (dosen the_dsn){  
     dsn.add(the_dsn);  
   }  
   public void addmhs (mahasiswa the_mhs){  
     mhs.add(the_mhs);  
   }  
   public void addkls (kelas the_kls){  
     kls.add(the_kls);  
   }  
   public void addmk (matkul the_mk){  
     mk.add(the_mk);  
   }  
   public void addbuku (buku the_buku){  
     buku.add(the_buku);  
   }  
   public void list(int id){  
     int no = 1;  
     switch(id){  
     case 1:  
     for(pegawai cd: pgw){  
       System.out.println(no++);  
       for(pegawai iterasi : pgw){  
         iterasi.print();  
       }  
     }  
     break;  
     case 2:  
     for(dosen cd: dsn){  
       System.out.println(no++);  
       for(dosen iterasi : dsn){  
         iterasi.print();  
       }  
     }  
     break;  
     case 3:  
     for(mahasiswa cd: mhs){  
       System.out.println(no++);  
       for(mahasiswa iterasi : mhs){  
         iterasi.print();  
       }  
     }  
     break;  
     case 4:  
     for(matkul cd: mk){  
       System.out.println(no++);  
       for(matkul iterasi : mk){  
         iterasi.print();  
       }  
     }  
     break;  
     case 5:  
     for(kelas cd: kls){  
       System.out.println(no++);  
       for(kelas iterasi : kls){  
         iterasi.print();  
       }  
     }  
     break;  
     case 6:  
     for(buku cd: buku){  
       System.out.println(no++);  
     }  
     break;  
   }  
   }  
 }  

3. Buku

 public class buku extends objek  
 {  
   private String pengarang;  
   private int halaman;  
   public buku (String name, int kode, String Pengarang, int Halaman)  
   {  
     super(name, kode);  
     pengarang = Pengarang;  
   }  
   public String get_pengarang()  
   {  
     return pengarang;  
   }  
   public int get_halaman()  
   {  
     return halaman;  
   }  
   public void print(){  
     System.out.println("Nama    : "+this.getnama());  
     System.out.println("Kode    : "+this.getid());  
     System.out.println("Pengarang  : "+this.get_pengarang());  
     System.out.println("Halaman   : "+this.get_halaman());  
   }  
 }  

4. Objek

 public class objek  
 {  
   private String nama;  
   private int id;  
   public objek(String name,int kode)  
   {  
     nama = name;  
     id = kode;  
   }  
   public String getnama(){  
     return nama;  
   }  
   public int getid(){  
     return id;  
   }  
 }  

5. Kelas

 public class kelas extends objek  
 {  
   private String ruangan;  
   public kelas (String name, int kode, String Ruangan)  
   {  
     super(name, kode);  
     ruangan = Ruangan;  
   }  
   public String get_ruangan()  
   {  
     return ruangan;  
   }  
   public void print(){  
     System.out.println("Nama  : "+this.getnama());  
     System.out.println("Kode  : "+this.getid());  
     System.out.println("Ruangan : "+this.get_ruangan());  
   }  
 }  

6. Mahasiswa

 public class mahasiswa extends objek  
 {  
   private String degree;  
   private String address;  
   public mahasiswa (String name, int kode, String derajat, String alamat)  
   {  
     super (name, kode);  
     degree = derajat;  
     address = alamat;  
   }  
   public String get_degree()  
   {  
     return degree;  
   }  
   public String get_address()  
   {  
     return address;  
   }  
   public void print(){  
     System.out.println("Nama  : "+this.getnama());  
     System.out.println("Kode  : "+this.getid());  
     System.out.println("Derajat : "+this.get_degree());  
     System.out.println("Alamat : "+this.get_address());  
   }  
 }  

7. Matkul

 public class matkul extends objek  
 {  
   private String dosen;  
   public matkul(String name, int kode, String Dosen)  
   {  
     super(name, kode);  
     dosen = Dosen;  
   }  
   public String get_dosen()  
   {  
     return dosen;  
   }  
   public void print(){  
     System.out.println("Nama    : "+this.getnama());  
     System.out.println("Kode    : "+this.getid());  
     System.out.println("Dosen    : "+this.get_dosen());  
   }  
 }  

8. Pegawai

 public class pegawai extends objek  
 {  
   private String bagian;  
   public pegawai (String name, int kode, String Bagian)  
   {  
     super(name, kode);  
     bagian = Bagian;  
   }  
   public String get_bagian()  
   {  
     return bagian;  
   }  
   public void print(){  
     System.out.println("Nama    : "+this.getnama());  
     System.out.println("Kode    : "+this.getid());  
     System.out.println("Bagian   : "+this.get_bagian());  
   }  
 }  

berikut saya lampirkan pula hasilnya: