Tugas PBO Music Organizer dan Auction Program

1. Music Player

Berikut adalah source code untuk music player.

Class MusicOrganizer

 import java.util.Scanner;  
 /**  
  * Write a description of class MusicOrganizer here.  
  *  
  * @author (your name)  
  * @version (a version number or a date)  
  */  
 public class MusicOrganizer  
 {  
   public static void MusicOrganizer(){  
     Music music = new Music();  
     Scanner scan = new Scanner(System.in);  
     int c;  
     while(true){  
       c = scan.nextInt();  
       switch(c){  
         case 1:  
         scan.nextLine();  
         String lagu = scan.nextLine();  
         music.tambah(lagu);  
         break;  
         case 2:  
         music.daftar();  
         break;  
         case 3:  
         int nomor = scan.nextInt();  
         music.mulai(nomor);  
         break;  
         case 4:  
         nomor = scan.nextInt();  
         music.stop(nomor);  
         break;  
         case 5:  
         nomor = scan.nextInt();  
         music.hapus(nomor);  
         break;  
       }  
     }  
   }  
 }  

Class Music

 import java.util.ArrayList;  
 /**  
  * Write a description of class Music here.  
  *  
  * @author (your name)  
  * @version (a version number or a date)  
  */  
 public class Music {    
   private ArrayList<String> playlist;  
   private Player play;  
   private int now,state;  
   public Music() {   
     playlist = new ArrayList<String>();   
     play = new Player();  
     now = -1;  
     state = 0;  
   }  
   public int jumlah() {   
     return playlist.size();   
   }  
   public void daftar() {   
     if(playlist.size()>0) {   
       for(int i=0;i<playlist.size();i++){  
         String filename = playlist.get(i);   
         System.out.println((i+1)+". "+filename);   
       }  
     }   
     else System.out.println("Tidak ada");  
   }  
   public void hapus(int index) {   
     if(index-1 >= 0 && index-1 < playlist.size()) {   
       playlist.remove(index);   
     }   
   }  
   public void tambah(String lagu) {   
     playlist.add(lagu);   
   }  
   public void mulai(int index){  
     now = index-1;  
     if(playlist.size()>0){  
       play.start(playlist.get(now));  
       state=1;  
     }  
     else System.out.println("Belum ada lagu");  
   }  
   public void stop(int index){  
     if(now == index-1 && state == 1){  
       play.stop(playlist.get(now));  
       state=0;  
     }  
     else System.out.println("Lagu belum berputar");  
   }  
 }  

Class Player

 /**  
  * Write a description of class Player here.  
  *  
  * @author (your name)  
  * @version (a version number or a date)  
  */  
 public class Player  
 {  
   private int index;  
   public void start(String lagu){  
     System.out.println("Playing: "+lagu);  
   }  
   public void stop(String lagu){  
     System.out.println(lagu+" has stopped ");  
   }  
 }  

Hasil

2. Auction Program
Berikut adalah source code untuk auction program.

Class Auction

 import java.util.ArrayList;    
 /**  
  * Write a description of class Auction here.  
  *  
  * @author (your name)  
  * @version (a version number or a date)  
  */  
 public class Auction    
 {  
   private ArrayList<Lot> barang; //daftar barang yang dilelang   
   private int nextBarang; //untuk pengkodean barang   
   public Auction() //inisiasi pelelangan baru   
   {  
     barang = new ArrayList<>();  
     nextBarang = 1;    
   }    
   public void masukkanBarang(String nama) //memasukkan barang ke daftar barang yang dilelang   
   {    
     barang.add(new Lot(nextBarang, nama));    
     nextBarang++;    
   }    
   public void tampilkanBarang() //menampilkan seluruh barang yang dilelang   
   {  
     for(Lot lot : barang) {  
       System.out.println(lot.toString());  
     }  
   }    
   public void buatPenawaran(int kode, Person penawar, long harga)    
   {    
     Lot selectedLot = getBarang(kode);    
     if(selectedLot != null) { //hanya bisa jika kode barang telah terdaftar   
       Bid bid = new Bid(penawar, harga);  
       boolean successful = selectedLot.bidFor(bid);  
       if(successful) {  
         System.out.println("Tawaran untuk nomor barang" + kode + " telah sukses.");  
       }  
       else {    
         Bid maksTawaran = selectedLot.getTertinggi(); //hanya bisa menawar dengan harga yang lebih tinggi daripada penawar sebelumnya   
         System.out.println("Nomor barang: " + kode +    
         " sudah memiliki tawaran: " +    
         maksTawaran.getHarga());    
       }    
     }    
   }    
   public Lot getBarang(int kode)    
   {    
     if((kode >= 1) && (kode < nextBarang)) {  
       Lot selectedLot = barang.get(kode - 1);    
       if(selectedLot.getKode() != kode) {    
         System.out.println("Eror internal: nomor lot " +    
         selectedLot.getKode() +    
         " telah diganti " +    
         kode);    
         // Don't return an invalid lot.    
         selectedLot = null;    
       }    
       return selectedLot;    
     }    
     else {    
       System.out.println("Nomor barang: " + kode +    
       " tidak tersedia.");    
       return null;    
     }    
   }  
   public void hentikan()  
   {    
     System.out.println("Pelelangan telah dihentikan.");    
     for(Lot lot : barang)    
     {    
       System.out.println(lot.getKode() + ": " +lot.getNama());    
       Bid bid = lot.getTertinggi();    
       if (bid==null)    
       {    
         System.out.println("Tidak ada tawaran untuk barang ini");    
       }    
       else    
       {    
         System.out.println("Barang ini telah dijual kepada " +    
         bid.getNama().getNama() + " dengan harga :\t"    
         + bid.getHarga());    
       }    
     }    
   }    
  }  

Class Bid

 /**  
  * Write a description of class Bid here.  
  *  
  * @author (your name)  
  * @version (a version number or a date)  
  */  
 public class Bid    
 {  
   private final Person penawar;    
   private final long harga;    
   public Bid(Person penawar, long harga)    
   {    
     this.penawar = penawar;    
     this.harga = harga;    
   }    
   public Person getNama()    
   {    
     return penawar;    
   }    
   public long getHarga()    
   {    
     return harga;    
   }    
 }  

Class Person

 /**  
  * Write a description of class Person here.  
  *  
  * @author (your name)  
  * @version (a version number or a date)  
  */  
 public class Person    
 {  
   private final String Nama;    
   public Person(String Nama)    
   {    
     this.Nama = Nama;    
   }    
   public String getNama()    
   {    
     return Nama;    
   }  
 }   

Class Lot

 /**  
  * Write a description of class Lot here.  
  *  
  * @author (your name)  
  * @version (a version number or a date)  
  */  
 public class Lot    
 {    
   private final int kodeBarang;    
   private String namaBarang;    
   private Bid maksTawaran;    
   public Lot(int kodeBarang, String namaBarang)    
   {    
     this.kodeBarang = kodeBarang;    
     this.namaBarang = namaBarang;    
     this.maksTawaran = null;    
   }    
   public boolean bidFor(Bid tawaran)    
   {    
     if(maksTawaran == null) {    
       maksTawaran = tawaran; //jika tidak ada tawaran sebelumnya   
       return true;    
     }    
     else if(tawaran.getHarga() > maksTawaran.getHarga()) {    
       maksTawaran = tawaran; //jika tawaran lebih tinggi daripada tawaran sebelumnya   
       return true;    
     }    
     else {    
       return false; //jika tawaran tidak lebih tinggi daripada tawaran sebelumnya   
     }    
   }    
   public String toString()    
   {    
     String details = kodeBarang + ": " + namaBarang;    
     if(maksTawaran != null) {    
       details += " Tawaran: " +    
       maksTawaran.getHarga();    
     }    
     else {    
       details += " (Tidak ada tawaran)";    
     }    
     return details;    
   }    
   public int getKode()    
   {    
     return kodeBarang;    
   }    
   public String getNama()    
   {    
     return namaBarang;    
   }    
   public Bid getTertinggi()    
   {    
     return maksTawaran;    
   }    
 }  

Sekian dan Terima Kasih.