opis exception

java.lang.RuntimeException: java.util.ConcurrentModificationException
        at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:663)
        at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:589)
        at net.minecraftforge.fml.common.FMLCommonHandler.onPostServerTick(FMLCommonHandler.java:265)
        at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:710)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:524)
        at java.lang.Thread.run(Thread.java:748)
Caused by: java.util.ConcurrentModificationException
        at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1386)
        at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
        at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
        at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151)
        at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174)
        at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
        at java.util.stream.ReferencePipeline.forEachOrdered(ReferencePipeline.java:423)
        at mcp.mobius.opis.data.managers.TileEntityManager.getCumuativeAmountTileEntities(TileEntityManager.java:124)
        at mcp.mobius.opis.events.OpisServerTickHandler.tickEnd(OpisServerTickHandler.java:101)
        at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_343_OpisServerTickHandler_tickEnd_ServerTickEvent.invoke(.dynamic)
        at net.minecraftforge.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:90)
        at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:651)
        ... 5 more