Lab 9

weight = 19

Overview

For this lab, you will revise your Lab 8 solution by introducing arrays of Dogs in the DogWalkingService class.

Assignment

The previous version of the DogWalkingService class you implemented was limited in that you could only walk three dogs. Things have been going great, and you've decided to open a business and handle more than three dogs.

The following diagram shows the revised API that you are to implement. Detail on each change is given below.

Dog

-name: String {readOnly}
-prefersFastWalks: boolean {readOnly}
-solidProductionRate: int {readOnly}
-totalWalks: int
-totalTimesPeed: int
-totalTimesPooped: int
+DOG_NAMES: String[] = {"Spot", "Spotless", "Yippee", ...} {readOnly}

+Dog()
+Dog(name: String)
+Dog(name: String, prefersFastWalks: boolean, solidProductionRate: int)
+getName(): String
+walk(lengthInMinutes: int, isFast: boolean): boolean
+getNumberOfWalks(): int
+getTotalTimesPeed(): int
+getTotalTimesPooped(): int
+toString(): String
-makePluralIfAppropriate(quantity: int, word: String): String

Changes to `Dog`

You will need to make the following changes to your Dog class:

Add a class constant that is an array of at least ten potential dog names.
Add a no-arg constructor that will select a name for the dog at random from the array of dog names.
Add a makePluralIfAppropriate() method that can be used to ensure that the toString() method makes use of the correct pluralization of words. For example, instead of "Spot is a slow walker who peed 48 times and pooped 1 times.", it should produce "Spot is a slow walker who peed 48 times and pooped 1 time."

DogWalkingService

-dogs: Dog[] {readOnly}
-numberOfDogs: int
~~-dog1: Dog {readOnly}~~
~~-dog2: Dog {readOnly}~~
~~-dog3: Dog {readOnly}~~
-successCount: int
-numberOfWalks: int
-totalMinutes: int

~~+DogWalkingService(dog1: Dog, dog2: Dog, dog3: Dog)~~
+DogWalkingService(capacity: int)
+enrollDog(dog: Dog): boolean
+removeDog(index: int): Dog
+getSummary(): String
+walk2Dogs(minutes: int): boolean
+walk2Dogs(minutes: int, isFast: boolean): boolean
+walkAllDogs(minutes: int): boolean
+walkAllDogs(minutes: int, isFast: boolean): boolean
+getNumberOfWalks(): int
+getTotalMinutesWalked(): int
+getNumberOfSuccessfulWalks(): int
+getDogs(): Dog[]
+getNumberOfDogs(): int
+getSpacesLeft(): int

Changes to `DogWalkingService`

The dogs array is used to keep track of all the dogs managed by the dog walking service. The dogs should be added to the array from left to right. For example, if there are two dogs being managed by the service, they should be stored in index 0 and 1 of the dogs array.

You will need to make the following changes to your DogWalkingService class:

Remove the instances to individual dog1, dog2, and dog3 and replace them with an array of dogs.
Add an attribute to keep track of the number of dogs enrolled. Note that the service should start with no dogs. The enrollDog() method must be used to add dogs to the service.
Replace the old constructor with one that accepts a capacity that will determine the length of the dogs array.
Add methods to enroll and remove a dog from the service.
- enrollDog(Dog dog) should add dog to dogs, unless there are no spaces left. The method returns true if and only if the dog was added to the dog walking service.
- removeDog(int index) should remove the dog at the specified index and shift all dogs after index one spot to the left.
Add a method to get all of the dogs enrolled in the service.
Add a method to get how many dogs are currently enrolled.
Add a method to get how many additional dogs can be enrolled before the service reaches capacity.
Update the remaining methods to work with the array of dogs instead of dog1, dog2, and dog3.

Program

You must design the Lab9 class that is a program that:

Asks the user how many dogs they would like to walk.
Creates a DogWalkingService object that can support 25% more dogs than the user would like to walk.
Adds randomly named dogs to the DogWalkingService instance until there are as many dogs as the user wants to walk enrolled in the walking service.
Asks the user how many walks they would like to take today.
Conducts the walks.
Displays a summary of the results.

Acknowledgement

This laboratory assignment was developed by Dr. Chris Taylor.

See your professor's instructions for details on submission guidelines and due dates.