Java OOP game

There are several star systems in the galaxy - Artemis Tau, Serpent Nebula, Hades Gamma and Kepler Verge. Starships can travel from one star system to another (if they are neighbouring) and fight other starships. A starship has health, shields, damage, fuel and shoots a specific projectile when attacking another ship. There are 3 types of starships - Frigates, Cruisers and Dreadnoughts, and each one respectively has different characteristics.