Solved Minecart Spawner Data and Falling Block Data

Hello everyone!

I have been experimenting with the development build for Minecraft 1.5, and I am trying to get NBT tags for spawner data to set to spawner minecarts and falling blocks. So far I have basic minecarts and falling entity blocks working, however I cannot seem to set the actual spawner NBT data.

I have tried using reflection to get the NBT, as specifed here: http://forums.bukkit.org/threads/getting-entity-nbt-data.113049/ and roughly the same for setting, with the exception of invoking "a(NBTTagCompound)" instead of "b(NBTTagCompound)".

After I got the data, I would add the tags specified here: http://www.minecraftwiki.net/wiki/Chunk_format#Vehicles

Finally, I would set the modified tags back to the mob. This works totally for pretty much everything (custom name tags, potion effects, tile ID/damage, etc.). No errors are thrown ever, just, nothing seems to happen in the case of spawner data.

Any ideas about what I could be doing wrong? Or is it not implemented to do this all yet?

Thanks!
~thebiologist13

 

the spawner data may be cached inside the class of the spawner, so modifying the underlying nbt may not work

 

Ok, is there a way to change the cached NBT then? Or a way to spawn it with specific data?

Thanks!
~thebiologist13

 

Any ideas anyone? I am stumped. I did find out that it's something wrong with my NBT setter though. It won't apply the NBT data to spawner minecarts or falling blocks, but it will for other entities like pigs.

My setter:

Code:java

public void setEntityNBT(Entity e, NBTTagCompound n) {
    net.minecraft.server.v1_5_R1.Entity nms = ((CraftEntity) e).getHandle();
    Class<?> entityClass = nms.getClass();
    Method[] methods = entityClass.getMethods();
    for (Method method : methods) {
        if ((method.getName() == "a")
                && (method.getParameterTypes().length == 1)
                && (method.getParameterTypes()[0] == NBTTagCompound.class)) {
            try {
                method.setAccessible(true);
                method.invoke(nms, n);
            } catch (Exception ex) {
                ex.printStackTrace();
            }
        }
    }
}

One more note, I did put a debug check in, and the compound I passed into my setter has all the data it needs in it.

Thanks in Advance!
~thebiologist13

Oh my gosh I figured it out! It was sort-of cached like ferrybig said. I ended up having to use some more reflection to get it to work.

Here is the way I set spawner minecart NBT now:

Code:java

EntityMinecartAbstract abs = ((CraftMinecart) entity).getHandle();
    EntityMinecartMobSpawner cart = (EntityMinecartMobSpawner) abs;
 
    //Show custom name is a value in my plugin.
    if(data.showCustomName()) {
        abs.a(data.getName()); //Sets the name. Not even sure if it matters though...
    }
 
    //The item type thing is internal to my plugin, CustomSpawners
    if(!data.getItemType().getType().equals(Material.AIR)) {
        int id = data.getItemType().getTypeId();
        int dur = (int) data.getItemType().getDurability();
        cart.a(true); //Show tile
        cart.k(id); //Tile ID
        cart.l(dur); //Tile durability
    }
 
    //Spawner data is yet another thing internal to my plugin. It is a class with a ton of
    //data related to spawners.
    if(data.getSpawnerData() != null && entity instanceof SpawnerMinecart) {
        NBTTagCompound spawnerData = new NBTTagCompound();
        NBTBase[] props = nbt.getPropertyArray(data.getSpawnerData());
        for(NBTBase base : props) {
            if(base.getName().equals("id") || base.getName().equals("x") ||
                    base.getName().equals("y") || base.getName().equals("z")) {
                continue;
            }
            nbtComp.set(base.getName(), base);
            spawnerData.set(base.getName(), base);
        }
 
        try {
            Field theSpawner = cart.getClass().getDeclaredField("a");
            theSpawner.setAccessible(true);
            MobSpawnerAbstract spawner = (MobSpawnerAbstract) theSpawner.get(cart);
            spawner.a(spawnerData);
        } catch(Exception e) {
            e.printStackTrace();
        }
}

And for falling blocks:

Code:java

NBTTagCompound nbtComp = nbt.getEntityNBT(entity); //This gets the base nbt of the entity.
EntityFallingBlock block = ((CraftFallingSand) entity).getHandle();
//Now we set the TileEntityData tag to the data from my spawner class.
nbtComp.setCompound("TileEntityData", nbt.getSpawnerNBT((ISpawner) data.getSpawnerData()));
try {
    Class<?> entityClass = block.getClass();
    Method[] methods = entityClass.getDeclaredMethods();
    for (Method method : methods) {
        if ((method.getName() == "a")
                && (method.getParameterTypes().length == 1)
                && (method.getParameterTypes()[0] == NBTTagCompound.class)) {
            method.setAccessible(true);
            method.invoke(block, nbtComp);
        }
    }
} catch(Exception e) {
    e.printStackTrace();
}

Yay code!
~thebiologist13

EDIT by Moderator: merged posts, please use the edit button instead of double posting.