Removing a drop from a mob

I am getting this error message :


23:27:32 [SEVERE] Could not pass event ENTITY_DEATH to MyPlugin
java.util.ConcurrentModificationException
at java.util.AbstractList$Itr.checkForComodification(Unknown Source)
at java.util.AbstractList$Itr.next(Unknown Source)
at randomman159.MyPlugin.OMCEntityListener.onEntityDeath(OMCEntity
Listener.java:27)


The code is simply :

Code:

for (ItemStack d : event.getDrops())
            {
                if (d.getType() == Material.COOKED_BEEF)
                    event.getDrops().remove(d);
            }

Any ideas? Or better ways of stopping a mob from dropping an item?

 

The ConcurrentModificationException means you cannot modify the collection event.getDrops() (a List) while you're iterating over the same collection.

I'm not even sure you should be trying to modify that collection directly at all. The event is missing a setDrops() manipulator, and the event will be forwarded to other plugins/listeners who may have only allowed/denied the event on the basis of the drops.

If you really want to persist anyway, try changing the offending ItemStack to something benign-- change that cookedbeef to pork, for example. The alternative would be to mark the event as cancelled-- no drops at all, but maybe no death either.

 

Code:

ArrayList<ItemStack> remove = new ArrayList<ItemStack>();

            for (ItemStack d : event.getDrops())
            {
                if (d.getType() == Material.RAW_BEEF || d.getType() == Material.COOKED_BEEF)
                    remove.add(d);
            }

            for (ItemStack d : remove)
            {
                event.getDrops().remove(d);
            }

This solved my problem. Thanks anyway!