Jack Robert Whiffen was at a caravan park in Moruya with his girlfriend in March when he got into a verbal stoush with a man named Scott Napper.

The fight turned physical but quickly dissolved and the pair went their separate ways. However a few hours later, Whiffen heard a commotion outside his van and saw a group of men, two of whom he recognised: Napper and a second man named Will Holmes.

Arming himself with a knife, Whiffen chased after the group and confronted Holmes, who was also armed with a knife. The pair goaded each other but agreed to drop the knives and fight with their fists.

However, mid-way through the fight, Napper picked up Whiffen's discarded knife and stabbed him in the chest, causing a puncture to his lung.

Whiffen was hospitalised but later charged with wielding a knife in a public place. Napper was charged with reckless wounding.

Whiffen pleaded guilty to that charge and a host of others in Wollongong Local Court on Tuesday, including two more offences in Corrimal and where knives or machettes were used as weapons.

Already serving an intensive corrections order in lieu of a full-time jail for a previous offence, Whiffen sought another ICO as punishment, saying he wanted to change his ways.

However Magistrate Roger Clisdell said Whiffen's last chance had come and gone.

"His performance on his (current) ICO has been less than satisfactory," he said, adding all attempts to have Whiffen treated by psychologists for his mental health issues and post-traumatic stress disorder from childhood had been unsuccessful.

He said Whiffen's traumatic, "out of control" childhood had included him becoming addicted to drugs at the age of 10 and becoming homeless in his teens.

However, Magistrate Clisdell said Whiffen's behaviour could not be excused.

"We simply can't have people in the community armed with knives and machettes threatening people," he said.

He sentenced Whiffen to two years behind bars, with a non-parole period of eight months.

Whiffen began yelling "f--k" at the top of his lungs after the sentencing was explained to him by his lawyer.

He then repeatedly punched himself in the head with his right hand while crying, yelling and moaning as the reality of the sentence sank in.

Corrective Services were forced to intervene and restrain Whiffen to stop further self-abusive behaviour. His girlfriend also managed to calm him.

Whiffen then went willingly with prison guards but continued to yell loudly as he descended down into the holding cells below the courthouse.

Whiffen will be released on bail in April 2020.