BankTellerSimulation

package bank;public class Customer {private final int serviceTime;public Customer(int tm){serviceTime=tm;}public int getServiceTime(){return serviceTime;}@Overridepublic String toString() {// TODO Auto-generated method stubreturn "["+serviceTime+"]  ";}}

package bank;import java.util.concurrent.ArrayBlockingQueue;public class CustomerLine extends ArrayBlockingQueue<Customer>{public CustomerLine(int capacity) {super(capacity);// TODO Auto-generated constructor stub}@Overridepublic String toString() {// TODO Auto-generated method stubif(this.size()==0)return "[empty]";StringBuilder builder = new StringBuilder();for(Customer c : this)builder.append(c);return builder.toString();}}

package bank;import java.util.Random;import java.util.concurrent.TimeUnit;public class CustomerGenerator implements Runnable{     private CustomerLine customers;     private static Random rand=new Random(47);     public CustomerGenerator(CustomerLine customers) {this.customers = customers;}@Overridepublic void run() {// TODO Auto-generated method stubtry{while(!Thread.interrupted()){TimeUnit.MILLISECONDS.sleep(rand.nextInt(300));customers.offer(new Customer(rand.nextInt(1000)));}}catch (Exception e) {// TODO: handle exceptionthrow new RuntimeException("Customer Generator interrupt!");}System.out.println("Customer Generator end!");}     }

package bank;import java.util.concurrent.TimeUnit;public class Teller implements Runnable,Comparable<Teller>{private static int counter=0;private int id=counter++;private CustomerLine customers;private int serviceNumber;private boolean serviceCustomer;public Teller(CustomerLine line){customers=line;serviceCustomer=true;}public synchronized void doSomethingElse(){serviceNumber=0;serviceCustomer=false;}public synchronized void serviceCustomers(){serviceCustomer=true;notifyAll();}@Overridepublic void run() {// TODO Auto-generated method stubtry{while(!Thread.interrupted()){Customer customer = customers.take();TimeUnit.MILLISECONDS.sleep(customer.getServiceTime());synchronized (this) {  serviceNumber++;  while(!serviceCustomer)  wait();}}}catch(InterruptedException e){throw new RuntimeException("Teller interrupt");}System.out.println("Teller service end!");}@Overridepublic int compareTo(Teller t) {// TODO Auto-generated method stubif(serviceNumber<t.serviceNumber) return -1;else if(serviceNumber==t.serviceNumber) return 0;else return 1;}@Overridepublic String toString() {// TODO Auto-generated method stubreturn "Teller "+id+" ";}}

package bank;import java.util.LinkedList;import java.util.List;import java.util.PriorityQueue;import java.util.Queue;import java.util.Random;import java.util.concurrent.ExecutorService;import java.util.concurrent.TimeUnit;public class TellerManager implements Runnable{private ExecutorService exec;private CustomerLine customers;private PriorityQueue<Teller> workingTellers=new PriorityQueue<Teller>();private Queue<Teller> tellerDoOtherThings=new LinkedList<Teller>();private int adjustTime;private static Random rand=new Random(47);public TellerManager(ExecutorService e,CustomerLine line,int tm){exec=e;customers=line;adjustTime=tm;Teller teller = new Teller(customers);exec.execute(teller);workingTellers.offer(teller);}@Overridepublic void run() {// TODO Auto-generated method stubtry{while(!Thread.interrupted()){TimeUnit.MILLISECONDS.sleep(adjustTime);adjustTellerNumber();System.out.print(customers + "{");for(Teller teller : workingTellers)System.out.print(teller);System.out.println("}");}}catch(InterruptedException e){throw new RuntimeException("Teller Manager Innterrupt!");}System.out.println("Teller Manager end!");}private void adjustTellerNumber() {// TODO Auto-generated method stubif(customers.size()/workingTellers.size()>2){if(tellerDoOtherThings.size()>0){Teller teller = tellerDoOtherThings.remove();teller.serviceCustomers();workingTellers.offer(teller);return ;}Teller teller = new Teller(customers);workingTellers.offer(teller);exec.execute(teller);return ;}if(customers.size()/workingTellers.size()<2&&customers.size()/workingTellers.size()>1){reassignOneTeller();}if(customers.size()==0){while(workingTellers.size()>1)reassignOneTeller();}}private void reassignOneTeller() {// TODO Auto-generated method stubTeller teller = workingTellers.poll();teller.doSomethingElse();tellerDoOtherThings.offer(teller);}}

package bank;import java.io.IOException;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;public class BankTellerSimulation {private static int MAX_SIZE=50;public static void main(String[] args) {// TODO Auto-generated method stub    ExecutorService exec = Executors.newCachedThreadPool();    CustomerLine customerLine = new CustomerLine(MAX_SIZE);    exec.execute(new CustomerGenerator(customerLine));    exec.execute(new TellerManager(exec, customerLine, 1000));    System.out.println("plase enter to end!");    try {System.in.read();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}    exec.shutdownNow();}}