In the Greymouth District Court on Tuesday, Greene admitted new charges of unlawfully possessing a knife and intentional damage.
The court was told that Greene was one of several young men who had been mouthing abuse at a group of tourists, including women, in Bright Street, Cobden, on February 4.
When some of the tourists advanced on them, Greene pulled the knife from under his jacket and yelled 'I've got a knife ... I've got a knife'.
He later told police that he had been too drunk to know whether he had a knife or not.
At 1am on December 9, Greene took exception to being evicted from a party.
He kicked in the panels of a rental car parked in the street, and then crossed the road to smash windows in the John Paul II School complex.
When he is released from jail Greene who had $13,000 in fines wiped in lieu of part of the prison sentence must pay $1200 reparation for damage to the car and $526 to the school.
Defence lawyer Eymard Bradley said Greene had sought a prison sentence as he wanted to get everything over and put crime behind him.
He had found his calling as a deckhand on fishing boats, and references suggested that he was a reliable, trustworthy employee.
Judge Raoul Neave said Greene's future was in his own hands: "You have a long life ahead of you, if you don't drink it away."
He ordered Greene to report to the Probation Service on his release from prison and to undertake any counselling or treatment recommended.
