Best Team

GOAL:

To learn and implement design patterns in an application.

Contributions:

• Indranil: Factory pattern for selecting the opponent Pokemon
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• Abhishek: Command pattern for selecting the moves, party Pokemon and bag items
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• Sushmitha: composite pattern to display the buttons on battle screen
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• Sai: Observer Pattern for tracking the Pokemon HP, video
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Link to the game video

Project Spiel - User Story

Project Description

We have made a game of Pokemon where the player can move around in the Pokemon world and fight with the wild Pokemon and the trainers with other pokemon.

• We have implemented the game in Greenfoot. User have the option to move around in the bushes and find a Pokemon to fight.
• Defeating the Pokemon adds to the experience of the Pokemon.
• Increase in exp leads to increase in the level and after a certain level the Pokemon evolves into its next stage.
• In the game, the user can battle with 5 trainers spread over the game and fight with them. Beating all 5 wins the game for the user.

High level Architecture Diagram

Game State Diagram

Class diagram

Factory patterns:

The Factory pattern is a creational pattern where we create object without exposing the creation logic to the client and refer to newly created object using a common interface.

• The IPokemon abstract class is the one which defines the interface which is to be exposed to the users of the classes.
• The Pokemon class inherits the IPokemon class and has a concrete implementation of the IPokemon interfact.
• The other Pokemon classes such as Arcanine, Arceus, etc provide variants which need to be instantiated in the Battle world.
• The Battle world has an object of the PokemonFactory class which is used to return instances of the Pokemon variants by using the getPokemon function.

Command pattern:

Command is a behavioral design pattern that turns a request into a stand-alone object that contains all information about the request. This transformation lets you pass requests as a method arguments, delay or queue a request’s execution, and support undoable operations.

• The ICommand class in the abstract class which is extended by all the button required on the battle screen.
• Selection class creates an instance of ICommand class and calls the show and hover method of the related class as per the command type.
• PartyTag and Fight are the other command which use the command pattern in the game in the same way as the attack commands

Composite pattern:

Composite is a structural design pattern that lets you compose objects into tree structures and then work with these structures as if they were individual objects. We have applied composite pattern to display option buttons on battle screen.

• The IDisplayInterface1 consists of 2 methods - addSubComponents(IDisplayComponent) and display(Battle). The interface is implemented by client class Battle and component class Buttons.
• The display(Battle) method is defined inside button subclasses.
• addSubComponent is used to add components by the client classes and then display method of each component is called in order to render the buttons in the Battle class.

Observer pattern:

Observer is a behavioral design pattern that lets you define a subscription mechanism to notify multiple objects about any events that happen to the object they’re observing. Observer Pattern is implemented to observe the health and level values for the pokemon class. Pokemon is the subject and BattleTag class is the observer.