public LauncherDestroyer findDestroyerById(int destroyerId) {
		LauncherDestroyer user_destroyer = null;
		for (LauncherDestroyer launcher_destroyer : getWarLauncherDestroyer()) {
			if (launcher_destroyer.getLauncherId() == destroyerId) {
				user_destroyer = launcher_destroyer;
				break;
			}
		}
		if (user_destroyer != null) {
			return user_destroyer;
		} else {
			return null;
		}
	}