I have been trying for weeks to add functionality to my mob spawner which would run a check on a specific in game tick for all objects (mobs) within a specific radius and then if this check finds that the mobs exist it despawns them. I have been very unsuccessful. Currently I have a tile entity which I created called mobspawner and it has a working timer which is synced with the minecraft in game ticks. This mob spawner has the functionality to spawn mobs at a specific game time and does so forever. This is a problem since it eventually crashes the game due to too many entities being present. does anyone know of a way to implement such functionality? Any help is very much appreciated.

this is the method your looking for:

this.worldObj.getEntitiesWithinAABB(par1Class, par2AxisAlignedBB)

it gets all the entity's within the AABB.

I have found the following

 

AxisAlignedBB axisalignedbb = AxisAlignedBB.getAABBPool().getAABB((double)xCoord, (double)yCoord, (double)zCoord, (double)(xCoord + 1), (double)(yCoord + 1), (double)(zCoord + 1)).expand(1, 1, 1);

            List list = worldObj.getEntitiesWithinAABB(Entity.class, axisalignedbb);

            Iterator iterator = list.iterator();

            Entity ent;

            while (iterator.hasNext()){

                ent = (Entity) iterator.next();

                if(!(ent instanceof EntityLivingBase)){

                (EntityLivingBase) ent).setDead();

                }

            }

 

but cant seem to get it to work any ideas?