Program: 179526
Project: 179526
Buggy source:
@Override public void run(){
  while (!stopOperation) {
    try {
      if (requestAccumulationBuffer.size() != 0) {
        for (        ItemPickupRequest req : requestAccumulationBuffer) {
          if (req.shouldBeRemoved == false) {
            if (LokemonServerVariables.itemMap.containsKey(req.itemId)) {
              if (System.currentTimeMillis() - req.requestTimeStamp > LokemonServerVariables.pickupLatency) {
                boolean earliestRequest=true;
                for (int i=0; i < requestAccumulationBuffer.size(); i++) {
                  if (requestAccumulationBuffer.get(i) != req) {
                    if (requestAccumulationBuffer.get(i).itemId == req.itemId) {
                      if (req.requestTimeStamp > requestAccumulationBuffer.get(i).requestTimeStamp) {
                        earliestRequest=false;
                        break;
                      }
                    }
                  }
                }
                if (earliestRequest) {
                  req.sendAccept();
                  LokemonServerVariables.itemMap.remove(req.itemId);
                }
              }
            }
 else {
              req.sendReject();
            }
          }
        }
      }
      for (int i=requestAccumulationBuffer.size() - 1; i >= 0; i--) {
        if (requestAccumulationBuffer.get(i).shouldBeRemoved) {
          requestAccumulationBuffer.remove(i);
        }
      }
      if (System.currentTimeMillis() - itemSpawnTime > LokemonServerVariables.itemSpawnTimer) {
        itemSpawnTime=System.currentTimeMillis();
        if (LokemonServerVariables.itemMap.values().size() < LokemonServerVariables.maxItemsIngame) {
          if (LokemonServerVariables.playerList.size() >= 1) {
            for (            LokemonPlayer pl : LokemonServerVariables.playerList) {
              if (pl.getPosition() != null) {
                Location center=pl.getPosition();
                double randomDist=(Math.random() * (LokemonServerVariables.itemSpawnRangeMax - LokemonServerVariables.itemSpawnRangeMin)) + LokemonServerVariables.itemSpawnRangeMin;
                double randomAngle=Math.random() * 360;
                double x=center.getX() + (randomDist * Math.cos(randomAngle) / LokemonDaemonThread.DEGREE_METER_HACK);
                double y=center.getY() + (randomDist * Math.sin(randomAngle) / LokemonDaemonThread.DEGREE_METER_HACK);
                LokemonPotion pot=new LokemonPotion(LokemonPotion.PotionType.values()[((int)Math.random() * LokemonPotion.PotionType.values().length)],itemIDCounter);
                pot.setPosition(new Location(x,y));
                itemIDCounter++;
                LokemonServerVariables.itemMap.put(pot.getId(),pot);
              }
            }
          }
        }
      }
      Thread.sleep(10);
    }
 catch (    InterruptedException e) {
    }
catch (    Exception e) {
      System.err.println("String_Node_Str" + e);
    }
  }
}

Fixed version (ground truth):
@Override public void run(){
  while (!stopOperation) {
    try {
      if (requestAccumulationBuffer.size() != 0) {
        for (        ItemPickupRequest req : requestAccumulationBuffer) {
          if (req.shouldBeRemoved == false) {
            if (LokemonServerVariables.itemMap.containsKey(req.itemId)) {
              if (System.currentTimeMillis() - req.requestTimeStamp > LokemonServerVariables.pickupLatency) {
                boolean earliestRequest=true;
                for (int i=0; i < requestAccumulationBuffer.size(); i++) {
                  if (requestAccumulationBuffer.get(i) != req) {
                    if (requestAccumulationBuffer.get(i).itemId == req.itemId) {
                      if (req.requestTimeStamp > requestAccumulationBuffer.get(i).requestTimeStamp) {
                        earliestRequest=false;
                        break;
                      }
                    }
                  }
                }
                if (earliestRequest) {
                  req.sendAccept();
                  LokemonServerVariables.itemMap.remove(req.itemId);
                }
              }
            }
 else {
              req.sendReject();
            }
          }
        }
      }
      for (int i=requestAccumulationBuffer.size() - 1; i >= 0; i--) {
        if (requestAccumulationBuffer.get(i).shouldBeRemoved) {
          requestAccumulationBuffer.remove(i);
        }
      }
      if (System.currentTimeMillis() - itemSpawnTime > LokemonServerVariables.itemSpawnTimer) {
        itemSpawnTime=System.currentTimeMillis();
        if (LokemonServerVariables.itemMap.values().size() < LokemonServerVariables.maxItemsIngame) {
          if (LokemonServerVariables.playerList.size() >= 1) {
            for (            LokemonPlayer pl : LokemonServerVariables.playerList) {
              if (pl.getPosition() != null) {
                Location center=pl.getPosition();
                double randomDist=(Math.random() * (LokemonServerVariables.itemSpawnRangeMax - LokemonServerVariables.itemSpawnRangeMin)) + LokemonServerVariables.itemSpawnRangeMin;
                double randomAngle=Math.random() * 360;
                double x=center.getX() + (randomDist * Math.cos(randomAngle) / LokemonDaemonThread.DEGREE_METER_HACK);
                double y=center.getY() + (randomDist * Math.sin(randomAngle) / LokemonDaemonThread.DEGREE_METER_HACK);
                int type=(int)(Math.random() * LokemonPotion.PotionType.values().length);
                LokemonPotion pot=new LokemonPotion(LokemonPotion.PotionType.values()[type],itemIDCounter);
                pot.setPosition(new Location(x,y));
                itemIDCounter++;
                LokemonServerVariables.itemMap.put(pot.getId(),pot);
              }
            }
          }
        }
      }
      Thread.sleep(10);
    }
 catch (    InterruptedException e) {
    }
catch (    Exception e) {
      System.err.println("String_Node_Str" + e);
    }
  }
}