get ColumnNumber返回当前事件结束时所在的那一列。
If the filter approves of the current event, it is exposed to the filtered reader.如果筛选器认可了当前事件,就将其公开给筛选过的读取器。
Similarly, getLocation() can get information about the location of the current event.类似的,getLocation() 可以获得当前事件的位置信息。