Exceptions when updating the timeline chart about solrmeter HOT 4 CLOSED

This an extract of the log when that passes... this is from a different moment, 
but with the same error:
[Timer-1]|DEBUG|[OperationTimeLineChartPanel]|12:34:06,079 | refreshing Time 
Line
[Timer-0]|DEBUG|[PieChartPanel]|12:34:06,189 | Refreshing pie chart
[Timer-1]|DEBUG|[OperationTimeLineChartPanel]|12:34:08,079 | refreshing Time 
Line
[Timer-0]|DEBUG|[PieChartPanel]|12:34:08,189 | Refreshing pie chart
[Timer-1]|DEBUG|[OperationTimeLineChartPanel]|12:34:10,079 | refreshing Time 
Line
[Timer-0]|DEBUG|[PieChartPanel]|12:34:10,189 | Refreshing pie chart
[Timer-0]|DEBUG|[PieChartPanel]|12:34:12,189 | Refreshing pie chart
[Timer-0]|DEBUG|[PieChartPanel]|12:34:14,189 | Refreshing pie chart
[Timer-0]|DEBUG|[PieChartPanel]|12:34:16,189 | Refreshing pie chart

I had the same exception with the query statistics

Viewing the source, i think that the method "refreshView" in the panels, should 
have a error handling so it can be logged or handled in some way

Hi ezechico, thanks for the help here. The bug is fixed on the trunk on 
revision 147. I'm also attaching a patch for fixing the problem on the 0.1.1 
version. I'm now using thread-safe collections on the statistics.