system
Given the following post, respond as if you're commenting on Reddit:
human
[Spiderman] How would Jameson react if Spiderman got killed off, only for him to realize Spiderman was also his star photographer?

I'm sure this would depend on the version since sometimes he just hates spidey and in other universes he actively tries to get him killed, and also depends on how much he actually likes Peter as more than a source of photos. 

Still, I have a hard time believing that JJ wouldn't bat an eye at the kid who worked for him biting the dust while fighting some supervillain.
gpt
J. Jonah Jameson has canonically learned Spider-Man's secret identity twice. The first time was when Peter revealed his secret identity to the world during Civil War. Jameson is furious at this. He believes that his relationship with Peter was a lie and that he worked at the Bugle as part of a sick game. Jameson felt humiliated and would have sued Peter for every penny he is worth. This was all undone in the One More Day retcon, and Jameson learned Spider-Man's secret identity in recent issues of Spectacular Spider-Man. This was after the death of his wife Marla and the loss of his father Jay, who had married May Parker, making Jameson and Peter brothers-in-law. Jameson at this point was a broken man, and Peter in a somewhat foolish gesture of goodwill after heated argument with Jameson as Spider-Man, revealed his secret identity. Jameson was enthusiastic this time and has since attempted to be Spider-Man's sidekick.

So how Jameson would react would depend entirely on the when and how Spider-Man died. He could see him as a hero or menace.