Andrew Charles Sangster (19) was told by Commissioner Francis Hamon in the Royal Court that his acts were ‘totally unacceptable’.
With two other boys Sangster also broke into Century Computers in the Parade, stealing nearly £1,000 worth in mobile phones and causing a further £1,000 damage.
On a separate occasion Sangster visited the home of Eugene Raimbault (70) with a young accomplice, having earlier seen him on his way to draw out £200 from the bank.
The court heard that Sangster demanded money, but when Mr Raimbault refused Sangster punched him and he fell to the floor.
Sangster then searched his trouser pockets for the cash but left when he could not find anything.
On that same day Sangster committed a further offence after being challenged by his accomplice about the assault on Mr Raimbault.
An argument ensued and Sangster repeatedly punched and kicked the victim, leaving him semi-conscious and with severe injuries.
