// this null pointer error appears to happens sometimes when u attempt to equip 1 hand right handed weaponerror handling client message [C] 14 UseItemjava.util.ConcurrentModificationException at java.util.AbstractList$Itr.checkForComodification(Unknown Source) at java.util.AbstractList$Itr.next(Unknown Source) at net.sf.l2j.gameserver.model.Inventory.setPaperdollItem(Inventory.java:299) at net.sf.l2j.gameserver.model.Inventory.equipItem(Inventory.java:455) at net.sf.l2j.gameserver.model.Inventory.equipItemAndRecord(Inventory.java:392) at net.sf.l2j.gameserver.clientpackets.UseItem.runImpl(UseItem.java:77) at net.sf.l2j.gameserver.clientpackets.ClientBasePacket.run(ClientBasePacket.java:56) at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source)// from inventory.java, here is the code surrounding lines 299, 455 and 392// comments beginning with "//--+" have been added as my notes and are not in the code originally// 299:L2ItemInstance setPaperdollItem(int slot, L2ItemInstance item) { L2ItemInstance old = _paperdoll[slot]; if (old != item) { if (old != null) { _paperdoll[slot] = null; old.setLocation(getBaseLocation()); old.setLastChange(L2ItemInstance.MODIFIED); int mask = 0; for (int i=0; i < PAPERDOLL_LRHAND; i++) { L2ItemInstance pi = _paperdoll[i]; if (pi != null) mask |= pi.getItem().getItemMask(); } _wearedMask = mask;//--+ next line is 299. "PaperdollListener listener" is shown as having the following problem in eclipse://--+ Syntax error on token(s), misplaced contruct(s) for (PaperdollListener listener : _paperdollListeners) listener.notifyUnequiped(slot, old); old.updateDatabase(); } if (item != null) { _paperdoll[slot] = item; item.setLocation(getEquipLocation(), slot); item.setLastChange(L2ItemInstance.MODIFIED); _wearedMask |= item.getItem().getItemMask();//--+ same error here on the paperdolllistener as above for (PaperdollListener listener : _paperdollListeners) listener.notifyEquiped(slot, item); item.updateDatabase(); } } return old; }//455://--+ no errors appear in the following code in eclipse case L2Item.SLOT_R_HAND: { if (_paperdoll[PAPERDOLL_LRHAND] != null) { setPaperdollItem(PAPERDOLL_LRHAND, null); setPaperdollItem(PAPERDOLL_LHAND, null); setPaperdollItem(PAPERDOLL_RHAND, null); } else {//--+ 455 below setPaperdollItem(PAPERDOLL_RHAND, null); } setPaperdollItem(PAPERDOLL_RHAND, item); break; }//392: public L2ItemInstance[] equipItemAndRecord(L2ItemInstance item) { Inventory.ChangeRecorder recorder = newRecorder(); try {//--+ 392 below equipItem(item, true); } finally { removePaperdollListener(recorder); } return recorder.getChangedItems(); }