Why Did Stradlater Punch Holden?

Why Did Stradlater Punch Holden? Holden and Stradlater fight because Stradlater has had a date with Jane Gallagher. They also fight because Stradlater acts entitled and asks Holden to write his English composition while Stradlater is on the date with Jane. Did Stradlater punch Holden? When Stradlater nonchalantly refuses to tell Holden any of the