According to wikipedia “novel” in and of itself is a genre, and it is the genre that Catcher in the Rye falls into.

I’d go so far as to say “proto-young adult,” but I’ve never read any of his other works.

Catcher in the Rye has a taste of the Jewish angst that appears so vividly in the later work by Philip Roth, Portnoy’s Complaint. It is somewhat disguised as Holden seems to be attending a prep school that is an old-WASP bastion. You can see it more in see of the short stories, as the story in which a young girl comes home to ask why it is so horrible to be called a “kite.”

Mid 20th Century Urban Angst.

Existentialist fiction.

Salinger hit the angst motif right on the head in pretty much every one of his works. And all of his characters had a presumably great childhood, but still hold a lot of resentment towards their parents and authority figures. So bildungsroman, definitely, with upper class angst, but also a shame of being so fortunate.

Early-Emo.

seriously.

Classic 20th century American novels.

Postmodern anti-social individualism.

Teenage angst.

Either that, or CIA assassin training trigger.

Late modernism. Early postmodernism. Subjectivity plays a huge role in Catcher in the Rye, especially since the story is told from the POV of an unreliable narrator.