Tugas PBO A - Auction System

October 07, 2018

Tugas PBO A - Auction System

Kali ini tugas PBO A yaitu membuat Auction System.

Nama : Ifta Jihan N (05111740000034)

Kelas : PBO A

Terdapat 4 class yang saya pakai, yaitu:

1. Auction

2. Person

3. Bid

4. Lot

Source code:

1. Auction

 import java.util.ArrayList;  
 /**  
  * Auction.  
  * @author Ifta Jihan N (05111740000034)  
  * PBO A 07/10/2018  
  */  
 public class Auction  
 {  
   //The list of Lots in this auction   
   private ArrayList<Lot> lots;   
   //The number that will be given to the next lot entered   
   private int nextLotNumber;    
   public Auction() //create a new auction  
   {   
    lots = new ArrayList<Lot>();   
    nextLotNumber = 1;   
   }   
   //Enter a new lot into the auction  
   public void enterLot(String description)   
   {   
    lots.add(new Lot(nextLotNumber, description));   
    nextLotNumber++; //description. A description of the lot  
   }   
   //Show the full list of lots in this auction    
   public void showLots()   
   {   
    for(Lot lot : lots)   
    {   
     System.out.println(lot.lotDetails());   
    }   
   }   
   //Make a bid for a lot   
   //A message is printed indicating whether the bid is succesful or not    
   public void makeABid(int lotNumber, Person bidder, long value)   
   {   
    //lotNumber. The lot being bid for  
    // bidder. The person bidding for the lot  
    // value The value of the bid  
    Lot selectedLot = getLot(lotNumber);   
    if (selectedLot != null)   
    {   
     boolean succesful = selectedLot.bidFor(new Bid(bidder, value));   
     if (succesful)   
     {   
      System.out.println("The bid for lot number " + lotNumber + " was succesful.");   
     }   
     else   
     {   
      //Report which bid is higher   
      Bid highestBid = selectedLot.getHighestBid();   
      System.out.println("Lot number: " + lotNumber + " already has a bid of: " + highestBid.getValue());   
     }   
    }   
   }   
   //Return the lot with the given number. Return null if a lot with this number doesn't exist    
   public Lot getLot(int lotNumber)   
   { //lotNumber. The number of the lot to return  
    if((lotNumber >= 1) && (lotNumber < nextLotNumber))   
    {   
     //The number seems to be reasonable   
     Lot selectedLot = lots.get(lotNumber-1);   
     //Include a confidence check to be sure we have the right lot   
     if (selectedLot.getNumber() != lotNumber)   
     {   
      System.out.println("Internal error: Lot number " + selectedLot.getNumber() + " was returned instead of " + lotNumber);   
      selectedLot = null;   
     }   
     return selectedLot;   
    }   
    else   
    {   
     System.out.println("Lot number: " + lotNumber + " does not exist.");   
     return null;   
    }   
   }   
   // Close an auction. Print the final status of each lot   
   public void close()   
   {   
    System.out.println("Closing auction.");   
    for (Lot lot : lots)   
    {   
     System.out.println(lot.getNumber() + ": " + lot.getDescription());   
     if (lot.getHighestBid() == null)   
     {   
      System.out.println ("No bids for this Lot");   
     }   
     else   
     {   
      Bid highestBid = lot.getHighestBid();   
      System.out.println(" sold to " + highestBid.getBidder().getName() + " for " + highestBid.getValue());   
     }   
    }   
   }   
 }

2. Person

 /**  
  * Person.  
  * @author Ifta Jihan N (05111740000034)   
  * PBO A 07/10/2018  
  */  
 public class Person  
 {   
   private final String name;   
   //Create a new person with the given name.   
   public Person (String name)   
   {   
    this.name = name;   
   }   
   //return the person's name   
   public String getName()   
   {   
    return name;   
   }   
 }

3. Bid

 /**  
  * Bid.  
  * @author Ifta Jihan N (05111740000034)  
  * PBO A 07/10/2018  
  */  
 public class Bid  
 {  
   //The person making the bid   
   private final Person bidder;   
   //The value of the bid.   
   private final long value;   
   //Create a bid   
   public Bid(Person bidder, long value)   
   {   
    this.bidder = bidder; //bidder. who is bidding for the lot  
    this.value = value;  //value. The value of the bid  
   }   
   //return the bidder  
   public Person getBidder()   
   {   
    return bidder;   
   }   
   //return the value of the bid  
   public long getValue()   
   {   
    return value;   
   }   
 }

4. Lot

 /**  
  * Lot.  
  * @author Ifta Jihan N(05111740000034)  
  * PBO A 07/10/2018  
  */  
 public class Lot //class to model an item (or set of items) in an auction  
 {  
   //A unique identifying number.   
   private final int number;   
   //A description of the lot   
   private String description;   
   //The current highest bid for this lot.   
   private Bid highestBid;   
   //Construct a Lot, setting its number and description.    
   public Lot (int number, String description)   
   {   
    this.number = number; //The lot number  
    this.description = description; //A description of this lot  
    this.highestBid = null;   
   }   
   //Attempt to bid for this lot.   
   //A succesful bid must have a value higher than any existing bid.    
   public boolean bidFor(Bid bid)   
   {   
    if (highestBid==null)   
    {   
     //There is no previous bid   
     highestBid=bid; //A new bid  
     return true; //return true if succesful  
    }   
    else if (bid.getValue() > highestBid.getValue())   
    {   
     //The bid is better than the previous one.   
     highestBid = bid;   
     return true;   
    }   
    else   
    {   
     //The bid is not better   
     return false;   
    }   
   }   
   //return A string representation of this lot's details.    
   public String lotDetails()   
   {   
    String details = number + ": " + description;   
    if (highestBid != null)   
    {   
     details += " Bid: " + highestBid.getValue();   
    }   
    else   
    {   
     details += " (No bid)";   
    }   
    return details;   
   }   
   //return the lot's number   
   public int getNumber()   
   {   
    return number;   
   }   
   // return the Lot's description  
   public String getDescription()   
   {   
    return description;   
   }   
   //return the highest bid for this lot  
   public Bid getHighestBid()   
   {   
    return highestBid;   
   }   
 }

Hasil Output:

Class dari project saya