“High School Musical 3’’ star Justin Martinappeared in Suffolk Superior Court on Tuesday and was sentenced to 18 months in the house of correction.

The charges against Martin stemmed from an incident that took place in Dorchester last summer, when Martin was accused of shooting guns with a 17-year-old on Bowdoin Avenue. Police alleged that he aimed a gun at officers as he fled.

The 22-year-old actor, who lives in California, pleaded guilty to all of the charges against him: assault with a dangerous weapon, unlawful discharge of a firearm within 500 feet of a dwelling, unlawful possession of a firearm, unlawful possession of ammunition, and unlawfully carrying a loaded firearm, according to Jake Wark, a spokesman for the Suffolk County District Attorney’s office.

Wark said Judge Peter Krupp sentenced Martin to 18 months followed by one year of probation with the conditions that he remain drug- and alcohol-free and stay away from the scene of the crime. The court ruled that his probation may be shortened if he obtains employment outside Massachusetts, Wark said.

Wark said Martin will serve his sentence in the Suffolk County House of Correction (unless the sheriff’s department places him elsewhere) and he’ll receive credit for the short period of time he was held before posting bail.

After the sentencing, Martin gave the following statement to People magazine: “I have matured a great deal in the past year and had to learn some hard lessons because of my actions. I should have acted more responsibly and taken my choices more seriously.’’

He continued: “This last year, I have been speaking at schools in Boston and educating high school students about making good choices, anti-gun violence, and drug awareness. I focus on being accountable for your actions and emphasize that one mistake doesn’t have to define your life. I appreciate everyone’s support, especially my family and friends for standing by me and knowing that my choices that night are not reflective of my true character. I look forward to moving past this time in my life and getting back to my career. Thank you for all the positive messages and support.’’