LibGDX: Cannot load a json file from assets folder

Question

I have a json file with data for all the tiles in my game that I store in the assets folder. I try to access and parse it using TileList dataList = json.fromJson(TileList.class, Gdx.file.internal("map-elements/tiles/tiles.json")) . This works fine for the desktop version but on the html version, after converting with gwt, I get these errors:

GwtApplication: exception: Error reading file: map-elements/tiles/tiles.json
Error reading file: map-elements/tiles/tiles.json
Couldn't find Type for class 'net.vediogames.archipelo.world.tiles.TileList'

TileList is a simple object that contains an array of TileData which can then be converted into Tile objects. I did it this way to make the json parsing easy.

Answer 1

The solution to the json error is simple. Instead of passing the FileHandle into the json parser, pass the string from the file like this:

TileList dataList = json.fromJson(TileList.class, Gdx.file.internal("map-elements/tiles/tiles.json").readString());

In the end, all I needed to do to solve that issue is add .readString() . As for the Couldn't find Type for class 'net.vediogames.archipelo.world.tiles.TileList' error, I also found a solution but it is more complicated.

JavaScript handles class references differently than Java. So I was not able to use TileList.class without first registering it so LibGDX can generate a Reflection. What I needed to do was add this line into my *.gwt.xml files:

<extend-configuration-property name="gdx.reflect.include" value="net.vediogames.archipelo.world.tiles.TileList" />

If you want a full tutorial about how reflection works and how to include packages or exclude, please view the official LibGDX tutorial here .

Answer 2

Your solution was not working for me, I still got the same error. After some hours of testing I got it to work, using your suggestions and by using the ClassReflection instead of referencing the class itself. Your example:

TileList dataList = json.fromJson(TileList.class, Gdx.file.internal("map-elements/tiles/tiles.json").readString());

looks in my working code like:

TileList dataList = (TileList) json.fromJson(ClassReflection.forName(TileList.class.getName()), Gdx.file.internal("map-elements/tiles/tiles.json").readString());

This is quite a pain in the a.. but I'm glad it is finally working now.