EnemyFactory.java

public class EnemyFactory {

	public static Enemy create(EnemyType enemyType) {

		Enemy enemy = null;
		
		switch (enemyType) {

		case SMALLENEMY:
			enemy = new SmallEnemy();
			break;
		case SMARTENEMY:
			enemy = new SmartEnemy();
			break;
		default:
			// throw some kind of exception
			throw new RuntimeException("the given enemy type does not existe ");
		}
		
		return enemy;
	}

}