Example code: ``` e.set("F4", "=SUM(F1,F2,F3)"); e.set("F4", "=SUM(F1:F3)"); ``` The exception is thrown by the HashMap class because the code tries to modify the Map when an Iterator is still iterating through it.
Example code:
The exception is thrown by the HashMap class because the code tries to modify the Map when an Iterator is still iterating through it.