Fans' favourite Hassell will start his 10th season at Oakwell after signing a new 12-month contract, while Cranie has put pen to paper on a new two-year deal.
Tykes manager David Flitcroft told the club's official website: "It's great to have Bobby on board.
"It took longer than it should of to get completed for a couple of reasons. The change at chief executive level and a situation where Bobby wanted to look after his wife and new-born child, which tells you everything about Bobby as a character.
"From a footballing perspective we have retained an experienced Championship player with pedigree and know-how. That experience will prove vital in strategic points of the season and in games.
"There's a feelgood factor around the club to the loyalty Bobby has shown. The fans love him, the club loves him and with Bobby signing the feeling seems to be mutual."
Flitcroft feels Cranie is also another crucial signing for the club, who have also signed winger Dale Jennings following his release from Bayern Munich and striker Chris O'Grady from Sheffield Wednesday.
"The signing of Cranes is another piece of business I am delighted with," Flitcroft added. "I spoke to him and his agent that much, I might as well have gone on holiday with the two of them.
"Cranes' form last season was outstanding. He got better and better with each game and his level of consistency impressed me.
"When you see a player on that curve you have to sign them or it's a year developing someone that's wasted and then you have to start again. We had to fight off other potential suiters that Cranes' form alerted."