He had been becoming increasingly aggressive, including trying to arm wrestle other patrons, and the refusal prompted him to lash out.
In the ensuing scuffle, he scratched the neck of a barmaid, Beth Loat, before punching duty manager Eilis Dowling twice in the face.
He accepted a sentence indication given by Judge Walker in March, and admitted charges of injuring Dowling with intent to injure, assaulting Loat, disorderly behaviour likely to cause violence, and breaching community detention.
Reading her victim impact statement in court, Dowling said she suffered a swollen jaw and whiplash that required her to wear a neck brace.
The attack took a psychological toll on her, and she suffered financially because payments from ACC did not cover her expenses, such as the cost of taxis.
She was only 155cm tall, and Hemi was "twice as wide and tall".
"A man of his size and strength knows the damage he can cause."
After 12 years as a duty manager, she had lost confidence in doing her job.
Counsel Tanya Surrey said Hemi "lashed out" after alcohol got the better of him.
The father of two sons, aged 6 and 7, "needs to do better for his tamariki".
Judge Walker said Hemi's explanation for his behaviour, that he had been refused contact with his sons that day, was "lame".
"If life hands you a problem, Mr Hemi, you can't resort to alcohol and end up punching a woman in the face."
He convicted Hemi and sentenced him to eight months' home detention at a Frankton address.
The defendant must not possess or consume alcohol or illicit drugs for the duration of the sentence and for six months' past the end date of the sentence, and must undergo intervention for drug and alcohol issues.
He must also pay Dowling reparation of $2500.
