It happened on Sunday, July 12 at about 3 a.m. at a store inside a strip mall in Middle Island.
Sixth Precinct officers responded to the scene after a 911 call.
The incident happened during a party at the store at 200 Middle County Road, according to police.
The victim, Domain Martin, 21, of Middle Island, was transported in a private vehicle to John T. Mather Memorial Hospital in Port Jefferson with non-life-threatening injuries.
The investigation is continuing.
Anyone with information is asked to call the Suffolk County PD Sixth Squad at 631-854-8652 or Crime Stoppers at 1-800-220-TIPS.
Click here to follow Daily Voice Massapequa and receive free news updates.