Question

JAVA CODE REQUIRED

A barber shop has one or more barbers who service customers as they arrive on a first- come-first-serve basis. Depending on the type of haircut a customer desires the service time varies. A barber shop also has a limited number of chairs for waiting customers. If all the chairs are filled, an arriving customer leaves without entering. For this assignment you will simulate a barber shop with customers arriving at various times each requiring a variety of service times. We are interested in observing the behavior of the barber shop at intervals of time. To simulate customers arriving at you will use a queue and to simulate customers waiting in a barber shop you will use a circular queue where the size is equal to the number of chairs available. Your program will read a text file that contains a customer's arrival time, his service time (i.e., the time the barber requires to give this customer the haircut he desires, ) and his name. Below is a sample input file. At each time interval report the customer that is arriving, the customer that is being serviced by the barber, and customers waiting in chairs. If the barber shop is full (i.e., all the chairs are filled) an arriving customer leaves without a haircut. (See the sample output file BarberShopOutput.docx. For the sample, the barber shop has 3 chairs available.) Your program needs to accommodate a variable number of chairs.

Answer 1

Barbershop.java

public class BarberShop{
  
   public static void main (String[] args){
  
       //instance variables
       CustomerData next, arriving;
       WaitingChairs waitingChair;
       ArrivalQueue arrivalQueue;
       Barber barber;
       int time;
  
       arrivalQueue = new ArrivalQueue();
       arrivalQueue.readFile();
       waitingChair = new WaitingChairs();
       barber = new Barber();
       time = 0;

       while(!arrivalQueue.isEmpty() || !waitingChair.isEmpty() || !barber.isEmpty())
       {
           System.out.println("Time = " + time + "\n");
          
          
           if(barber.isEmpty() && !waitingChair.isEmpty())
           {
               barber.addCust(waitingChair.peek());
               waitingChair.removeCustomer();
           }
          
           if(arrivalQueue.peek().getArrivalTime() == time)
           {
               if(waitingChair.isFull())
               {
                   System.out.println("All chairs are full");
                   System.out.println("\t" + arrivalQueue.peek().getName() + " leaves");
               }
               else
               {
                   waitingChair.addCustomer(arrivalQueue.peek());
                   System.out.println("A chair is available");
                   System.out.println("\t" + arrivalQueue.peek().getName() + " sits");
               }
               arrivalQueue.removeCustomer();
           }
          
           waitingChair.display();

           barber.display();

           System.out.println("\nArrival List");
           arrivalQueue.display();

           time++;
           barber.performService();

           System.out.println("\n-----------------------------\n");
       }
  

   }
}

CustomerData.java

public class CustomerData{
   //instance variables
   private int arrivalTime;
   private String name;
   private int serviceTime;
    private CustomerData next;

    //constructor
    public CustomerData(int conArrivalTime, int conServiceTime, String conName)
    {
        arrivalTime = conArrivalTime;
        serviceTime = conServiceTime;
        name = conName;
        next = null;
    }
   
    public CustomerData()
    {
        arrivalTime = 0;
        serviceTime = 0;
        name = null;
        next = null;
    }
   //methods

   public CustomerData getNext()
   {
       return next;
   }
  
   public String getName()
   {
       return name;
   }
  
   public int getArrivalTime()
   {
       return arrivalTime;
   }

   public int getServiceTime()
   {
       return serviceTime;
   }

   public void setNext(CustomerData nextCustomer)
   {
       next = nextCustomer;
   }
  
   public void setName(String newName)
   {
       name = newName;
   }
   
    public void setArrivalTime(int newArrivalTime)
    {
        arrivalTime = newArrivalTime;
    }

    public void setServiceTime(int newServiceTime)
    {
        serviceTime = newServiceTime;
    }
  
   public void display()
   {
       System.out.println("\t" + name + ": " + "arrival = " + arrivalTime + ':' + " service = " + serviceTime);
   }
  
   public boolean hasNext()
   {
       return next == null;
   }
}

  
WaitingChairs.java

public class WaitingChairs{
   //instance variables
   private int numItems = 0;
   private int firstCus;
   private int lastCus;
   private int size = 3;
   private CustomerData[] customer;

   //constructor
   public WaitingChairs()
   {
       size = 3;
       customer = new CustomerData[size];
       lastCus = 0;
       firstCus = 0;
   }
  
   public static void main (String[] args)
   {
       WaitingChairs temp = new WaitingChairs();
       temp.display();
       CustomerData test = new CustomerData(1,2,"jon");
       temp.addCustomer(test);
       temp.display();
       CustomerData test2 = new CustomerData(1,3,"matt");
       temp.addCustomer(test2);
       temp.display();
       //ask how to test peek
   }

  

   //methods

   public void addCustomer(CustomerData firstCustomer)
   {
       if(!isFull())
       {
           customer[firstCus] = firstCustomer;
           firstCus = (firstCus+1)%size;
           numItems++;
       }
       else
       {
           System.out.println("Queue is full!");
       }
   }

   public CustomerData removeCustomer()
   {
       CustomerData lastCustomer = customer[lastCus];
       lastCus = (lastCus+1) %size;
       numItems--;
       return lastCustomer;
   }

   public CustomerData peek()
   {
       return customer[lastCus];
   }  

   public void display()
   {
       if(!isEmpty())
       {
           System.out.println("\nChairs");
           for(int i = 0;i < numItems; i++){
               customer[(lastCus+i)%size].display();
           }
       }
       else
       {
           System.out.println("\nChairs are empty");
       }
   }

   public boolean isFull()
   {
       if(numItems == size)
       {
           return true;
       }
       else
       {
           return false;
       }
   }

   public boolean isEmpty()
   {
       if(numItems == 0)
       {
           return true;
       }
       else
       {
           return false;
       }
   }

}

ArrivalQueue.java

import java.util.Scanner;
import java.io.*;

public class ArrivalQueue{
   //instance variables
   private int numItems;
   private CustomerData firstCustomer;
   private CustomerData lastCustomer;

   //constructors
   public ArrivalQueue()
   {
   firstCustomer = null;
   lastCustomer = null;
   numItems = 0;
   }
   //methods
  
   //test code
   public static void main (String[] args)
   {
       ArrivalQueue test = new ArrivalQueue();
       test.readFile();
       test.display();
       CustomerData temp = new CustomerData(1,1, "temp");
       test.addCustomer(temp);
       test.removeCustomer();
       test.display();
       //ask how to test peek
   }

   public void addCustomer(CustomerData newFirstCustomer)
   {
       if(firstCustomer == null && lastCustomer == null)
       {
       firstCustomer = newFirstCustomer;
       lastCustomer = newFirstCustomer;
       numItems++;
       }
       else
       {
           firstCustomer.setNext(newFirstCustomer);
           firstCustomer = newFirstCustomer;
           numItems++;
       }
   }
  
   public CustomerData removeCustomer()
   {
       CustomerData c = lastCustomer;
       lastCustomer = lastCustomer.getNext();
       numItems--;
       return c;
   }
  
   public void display()
   {
       CustomerData tempCustomer = lastCustomer;
       while(tempCustomer != null)
       {
           tempCustomer.display();
           tempCustomer = tempCustomer.getNext();
       }
   }
  
   public CustomerData peek()
   {
       if(!isEmpty())
           return lastCustomer;
       else
       {
           CustomerData temp = new CustomerData(1,1, "temp");
           return temp;
       }
   }
  
   public boolean isEmpty()
   {
       if(numItems == 0)
       {
           return true;
       }
       else
       {
           return false;
       }
   }
  

   public void readFile(){
   String inputLine;
      
       Scanner fileInput;
       File inFile = new File("Barber.txt");
      
       System.out.println("Opening and reading file");
      
       try{
           fileInput = new Scanner(inFile);

           while(fileInput.hasNext())
           {
               CustomerData temp = new CustomerData();
               temp.setArrivalTime(fileInput.nextInt());
               temp.setServiceTime(fileInput.nextInt());
               temp.setName(fileInput.nextLine());
               addCustomer(temp);
           }
          
           fileInput.close();
          
       } // end try
      
       catch (FileNotFoundException e)
       {
           System.out.println(e);
           System.exit(1);       // IO error; exit program
       } // end catch  
          
   }
}
Barber.java

public class Barber{
   //instance variables
   private int serviceTime;
   private CustomerData customer;

   //constructors

   public Barber()
   {
       serviceTime = 0;
       customer = null;
   }

   //methods
  
   public boolean addCust(CustomerData newCust)
   {
       if(isEmpty())
       {
           customer = newCust;
           serviceTime = newCust.getServiceTime();
           return true;
       }
       else
       {
           return false;
       }
   }

   public boolean isEmpty()
   {
       if(customer == null)
       {
           return true;
       }
       else
       {
           return false;
       }
   }

   public void performService()
   {
       serviceTime--;
      
       if(serviceTime == 0)
       {
       removeCust();
       }
   }
  
   public void removeCust()
   {
       customer = null;
   }

   public CustomerData peek()
   {
       return customer;
   }

   public void display()
   {
       if(isEmpty())
       {
           System.out.println("\nBarber's chair is empty");
       }
       else
       {
           System.out.println("\nBarber");
           System.out.println(customer.getName() + " is chair " + serviceTime + " left");
       }
   }
}

Barber.txt

1   3   Bob
2   2   Jim
4   2   Bert
8   7   Greg
9   3   Tom
10   2   Earl
11   3   Jon
12   2   Bill