Hunter, 31, spent nine seasons with the Islanders, compiling 99 goals and 229 points in 459 NHL games. Acquired from Anaheim on May 23, 2000, Hunter was a Ducks' sixth-round draft choice in 1998. Due to a torn MCL, he played in just 17 games last season, scoring one goal.
Rolston, 38, was in his second stint as a Devil. He had 14 goals and 34 points last season as New Jersey missed the postseason for the first time since 1996.
The deal brings the Islanders closer to the NHL's salary floor of $48.3 million next season. And it also gives the Devils a little more cap space to try and sign restricted free agent Zach Parise, who is scheduled to go to salary arbitration next week.
Rolston is entering the final year of a deal that pays him a little more than $5 million. Hunter is scheduled to earn $2 million.