rentalmethods.java

程序设计模式java入门源码大全

import java.util.*;
import java.lang.Math;

public class RentalMethods
{
  final static int FULLY_RENTED = 0;
  final static int WAITING = 1;
  final static int GOT_APPLICATION = 2;
  final static int APARTMENT_RENTED = 3;
  Random random; 
  int numberApartments;
  int state = WAITING;

  public RentalMethods(int n)
  {
    numberApartments = n;
    random = new Random(System.currentTimeMillis());
  }
  
  public void getApplication()
  {
    switch (state)
    {
      case FULLY_RENTED:
        System.out.println("Sorry, we're fully rented.");
        break;
      case WAITING:
        state = GOT_APPLICATION;
        System.out.println("Thanks for the application.");
        break;
      case GOT_APPLICATION:
        System.out.println("We already got your application.");
        break;
      case APARTMENT_RENTED:
        System.out.println("Hang on, we're renting you an apartment.");
        break;
    }
  }

  public void checkApplication()
  {
    int yesno = random.nextInt() % 10;

    switch (state)
    {
      case FULLY_RENTED:
        System.out.println("Sorry, we're fully rented.");
        break;
      case WAITING:
        System.out.println("You have to submit an application.");
        break;
      case GOT_APPLICATION:
        if (yesno > 4 && numberApartments > 0) {
          System.out.println("Congratulations, you were approved.");
          state = APARTMENT_RENTED;
          rentApartment();
        } else {
          System.out.println("Sorry, you were not approved.");
          state = WAITING;
        }
        break;
      case APARTMENT_RENTED:
        System.out.println("Hang on, we're renting you an apartment.");
        break;
    }
  }

  public void rentApartment()
  {
    switch (state)
    {
      case FULLY_RENTED:
        System.out.println("Sorry, we're fully rented.");
        break;
      case WAITING:
        System.out.println("You have to submit an application.");
        break;
      case GOT_APPLICATION:
        System.out.println("You must have your application checked.");
        break;
      case APARTMENT_RENTED:
        System.out.println("Renting you an apartment....");
        numberApartments--;
        dispenseKeys();
        break;
    }
  }

  public void dispenseKeys()
  {
    switch (state)
    {
      case FULLY_RENTED:
        System.out.println("Sorry, we're fully rented.");
        break;
      case WAITING:
        System.out.println("You have to submit an application.");
        break;
      case GOT_APPLICATION:
        System.out.println("You must have your application checked.");
        break;
      case APARTMENT_RENTED:
        System.out.println("Here are your keys!");
        state = WAITING;
        break;
    }
  }

  public String getState()
  {
    switch (state)
    {
      case FULLY_RENTED:
        return "Fully rented.";
      case WAITING:
        return "Waiting.";
      case GOT_APPLICATION:
        return "Got an application.";
      case APARTMENT_RENTED:
        return "Rented an apartment.";
    }
    return "Unknown state.";
  }
}