Hotels near rail tracks

There is a hotel I'm interested in staying at for a week but it is beside rail tracks. Used by local lines and shinkansen that go into the nearby station. Is it safe to assume that the trains don't operate past midnight so I shouldn't be kept up all night?

Shinkansen operations stop about midnight. Local trains maybe until 1am, but local lines may run at 5am and the Shinkansen at 6am. This definitely depends on where you're at, meaning the town/city.

One time, I stayed in a 5th floor room overlooking tracks of a train station. The room was very well insulated if windows are closed, and the noise from the station was not an issue at all. It depends on how old the hotel is, I suppose.

You probably wouldn't notice the trains, but the trains usually stop over-night.
I will throw in a "however"; I stayed in a room adjacent to tracks where there were still freight trains during the night (that was no problem), but there was also track-work. The track-work was noisy with some of the cutting/power tools they were using - that kept me awake a while. Pretty rare though.

Modern hotels have good sound deadening. I'm doubtful you'd notice the noise enough to upset you.

This one is near Hakata Station and was built this year. Of course reading reviews of it they mention some noise but they don't say if it was also during the night.