Tugas PBO A - Auction

Tugas kali ini merupakan program mengenai pelelangan.

Class Auction:

 import java.util.ArrayList;  
 public class Auction  
 {  
   private ArrayList<Lot> lots; //list barang yang akan dilelang  
   private int nextLotNumber;  
   public Auction(){  
     lots = new ArrayList<Lot>();  
     nextLotNumber = 1;  
   }  
   public void enterLot(String description){//masukan barang baru  
     lots.add(new Lot(nextLotNumber, description));  
     nextLotNumber++;  
   }  
   public void showLots(){//menampilkan semua barang  
     for(Lot lot : lots){  
       System.out.println(lot.toString());  
     }  
   }  
   public void makeBid(int lotNumber, Person bidder, long value){  
     Lot selectedLot = getLot(lotNumber);  
     if(selectedLot != null){  
       Bid bid = new Bid(bidder,value);  
       boolean successful = selectedLot.bidFor(bid);  
       if(successful){  
         System.out.println(bidder.getName() + " berhasil melakukan penawaran.");  
       }  
       else{  
         //penawar tertinggi  
         Bid highestBid = selectedLot.getHighestBid();  
         System.out.println("Lot Number: " + lotNumber + "Penawaran: " + highestBid.getValue());  
       }  
     }  
   }  
   public Lot getLot(int lotNumber){  
     if((lotNumber >= 1) && (lotNumber < nextLotNumber)){  
       //nomor yang mungkin  
       Lot selectedLot = lots.get(lotNumber - 1);  
       if(selectedLot.getNumber() != lotNumber){  
         System.out.println("Error: Lot number " + selectedLot.getNumber() + "was retuened instead of " + lotNumber);  
         selectedLot = null;  
       }  
       return selectedLot;  
     }  
     else{  
       System.out.println("Lot number: " + lotNumber + "does't exist.");  
       return null;  
     }  
   }  
   public void close(){  
     System.out.println("Lelang Selesai.");  
     for(Lot lot : lots) {   
       System.out.println(lot.getNumber() + ": " +lot.getDescription());   
       Bid bid = lot.getHighestBid();   
       if (bid==null){   
         System.out.println("(No Bids for this lot.)");   
       }   
       else {   
         System.out.println( "sold to " +    
         bid.getBidder().getName() + " for "    
         + bid.getValue());   
       }   
     }  
   }  
 }  

Class Lot:

 public class Lot  
 {  
   private Bid highestBid; //Bid terbesar untuk Barang ini  
   private final int number;  
   private String description;  
   public Lot(int number, String description){  
     this.number = number;  
     this.description = description;  
   }  
   public boolean bidFor(Bid bid){  
     if(highestBid == null){  
       highestBid = bid; //Bid awal  
       return true;  
     }  
     else if(bid.getValue() > highestBid.getValue()){  
       highestBid = bid; //Bid lebih tinggi  
       return true;  
     }  
     else{  
       //Bid lebih rendah  
       return false;  
     }  
   }  
   public String toString(){  
     String details = number + ": " + description;  
     if(highestBid != null){  
       details += " Penawaran: " + highestBid.getValue();  
     }  
     else{  
       details += " Tidak ada penawaran";  
     }  
     return details;  
   }  
   public int getNumber(){  
     return number;  
   }  
   public String getDescription(){  
     return description;  
   }  
   public Bid getHighestBid(){  
     return highestBid;  
   }  
 }  

Class Person:

 public class Person  
 {  
   private final String name;  
   public Person(String name){  
     this.name = name;  
   }  
   public String getName(){  
     return name;  
   }  
 }  

Class Bid:

 public class Bid  
 {  
   private final Person bidder;  
   private final long value;  
   public Bid(Person bidder, long value){  
     this.bidder = bidder;  
     this.value = value;  
   }  
   public Person getBidder(){  
     return bidder;  
   }  
   public long getValue(){  
     return value;  
   }  
 }