Speaking afterwards, Mr Harvey asked for forgiveness from the boy who was left with a fractured skull and partial loss of hearing after the attack last July.
But he said he did not feel guilt about the attack, which he said he could not have prevented and warned that unless something is done to ease teachers stress the same thing could happen again.
He told the Daily Mirror: If it could happen to me it could happen to anyone.
There are lots of teachers who are ticking time bombs.
I know teachers who, because of stress, can’t hold a cup of coffee or are too frightened to cross the road.
It could happen again and probably will if something isn’t done.