  Logs play a crucial role in modern software systems, serving as a means for
developers to record essential information for future software maintenance. As
the performance of these log-based maintenance tasks heavily relies on the
quality of logging statements, various works have been proposed to assist
developers in writing appropriate logging statements. However, these works
either only support developers in partial sub-tasks of this whole activity; or
perform with a relatively high time cost and may introduce unwanted
modifications. To address their limitations, we propose FastLog, which can
support the complete logging statement generation and insertion activity, in a
very speedy manner. Specifically, given a program method, FastLog first
predicts the insertion position in the finest token level, and then generates a
complete logging statement to insert. We further use text splitting for long
input texts to improve the accuracy of predicting where to insert logging
statements. A comprehensive empirical analysis shows that our method
outperforms the state-of-the-art approach in both efficiency and output
quality, which reveals its great potential and practicality in current
real-time intelligent development environments.
