Flag Capture Kata

• Author: Sébastien Mosser
• Version: 0.1 (Feb 2017)

Objectives

• Start a Java project as a Maven multi-modules project
• Trigger the execution of a program with mvn exec:java
• Slice a complex requirements into small and vertical slices
• Unit test while developing business code

Problem Statement

A map is composed of a rectangular grid (height x width), which contains at least one flag somewhere in the map. A flag is uniquely identified by a name. A player is able to explore the map and capture flag when it discovers one. The player always spawns on the top-left corner of the map, facing East.

Starting Development with Maven

First of all, we create a Git repository (this very one), and clone it on the local computer

azrael:polytech mosser$ git clone https://github.com/polytechnice-si/3A_GL_FlagCapture.git
Cloning into '3A_GL_FlagCapture'...
remote: Counting objects: 4, done.
remote: Compressing objects: 100% (4/4), done.
remote: Total 4 (delta 0), reused 0 (delta 0), pack-reused 0
Unpacking objects: 100% (4/4), done.

Then, we create 3 maven projects:

• A root project (type: pom), which contains the two others and acts as parent (for shared configuration)
• A project to store the game, as a java program (type: jar)
• A project to store the player (type: jar), with a dependencies requiring the game

azrael:polytech mosser$ cd 3A_GL_FlagCapture/
azrael:3A_GL_FlagCapture mosser$ mkdir -p game/src/main/java game/src/test/java 
azrael:3A_GL_FlagCapture mosser$ mkdir -p player/src/main/java player/src/test/java 
azrael:3A_GL_FlagCapture mosser$ touch pom.xml game/pom.xml player/pom.xml

The Project Object Models (POMs) associated to these 3 projects are quite usual:

• game/pom.xml is a classical java project, loading JUnit for unit testing;
• player.pom.xml is another java project, loading game to access to the map
• pom.xml is a pom project, i.e., a maven project that does not produce executable code, but instead is used to model hierarchy among projects.

We can test through the command line that the projects are valid, executing mvn clean package returns a build success. Thus, we can import the project in our favorite IDE (aka, IntelliJ), and start project implementation.

• Achievement:
  • Start a Java project as a Maven multi-modules project

Building the Game

The game is quite simple. It exposes an interface to create and explore maps:

Link with sonar

mvn org.jacoco:jacoco-maven-plugin:prepare-agent clean package sonar:sonar

mvn -q exec:java