LibGdx Grouped Asset Loader

AssetLoader

public class Assets implements Disposable, AssetErrorListener {

	private static final String TAG = "Assets";
	private Logger logger;
	private AssetManager manager;
	private ObjectMap<String, Array<Asset>> groups;
	
	public Assets(String assetFile) {
		logger = new Logger(TAG, Logger.INFO);
		
		manager = new AssetManager();
		manager.setErrorListener(this);
		manager.setLoader(PhysicsData.class, new PhysicsLoader(new InternalFileHandleResolver()));
		manager.setLoader(AnimationData.class, new AnimationLoader(new InternalFileHandleResolver()));
		
		loadGroups(assetFile);
	}
		
	public void loadGroup(String groupName) {
		logger.info("loading group " + groupName);
		
		Array<Asset> assets = groups.get(groupName, null);
		
		if (assets != null) {
			for (Asset asset : assets) {
				manager.load(asset.path, asset.type);
			}
		}
		else {
			logger.error("error loading group " + groupName + ", not found");
		}
	}
	
	public void unloadGroup(String groupName) {
		logger.info("unloading group " + groupName);
		
		Array<Asset> assets = groups.get(groupName, null);
		
		if (assets != null) {
			for (Asset asset : assets) {
				if (manager.isLoaded(asset.path, asset.type)) {
					manager.unload(asset.path);
				}
			}
		}
		else {
			logger.error("error unloading group " + groupName + ", not found");
		}
	}
	
	public synchronized <T> T get(String fileName) {
		return manager.get(fileName);
	}
	
	public synchronized <T> T get(String fileName, Class<T> type) {
		return manager.get(fileName, type);
	}
	
	public boolean update() {
		return manager.update();
	}
	
	public void finishLoading() {
		manager.finishLoading();
	}
	
	public float getProgress() {
		return manager.getProgress();
	}

	@Override
	public void dispose() {
		logger.info("shutting down");
		manager.dispose();
	}
	
	@Override
	public void error(String fileName, Class type, Throwable throwable) {
		logger.error("error loading " + fileName);
	}
	
	private void loadGroups(String assetFile) {
		groups = new ObjectMap<String, Array<Asset>>();
		
		logger.info("loading file " + assetFile);
		
		try {
			XmlReader reader = new XmlReader();
			Element root = reader.parse(Gdx.files.internal(assetFile));

			for (Element groupElement : root.getChildrenByName("group")) {
				String groupName = groupElement.getAttribute("name", "base");
				
				if (groups.containsKey(groupName)) {
					logger.error("group " + groupName + " already exists, skipping");
					continue;
				}
				
				logger.info("registering group " + groupName);
				
				Array<Asset> assets = new Array<Asset>();
				
				for (Element assetElement : groupElement.getChildrenByName("asset")) {
					assets.add(new Asset(assetElement.getAttribute("type", ""),
										 assetElement.getAttribute("path", "")));
				}
				
				groups.put(groupName, assets);
			}
		}
		catch (Exception e) {
			logger.error("error loading file " + assetFile + " " + e.getMessage());
		}
	}
	
	private class Asset {
		public Class<?> type;
		public String path;
		
		public Asset(String type, String path) {
			try {
				this.type = Class.forName(type);
				this.path = path;
			} catch (ClassNotFoundException e) {
				logger.error("asset type " + type + " not found");
			}
		}
	}
}