Which kind of fresh-keeping jar is the most suitable for preserving coffee beans?

1. Is it a sealed can, or a jar with a single vent (like the ILLY jar)? Or a Starbucks bag with an one-way exhaust valve?

2. Coffee beans will emit carbon dioxide. Sealed cans are not conducive to the discharge of carbon dioxide. Can coffee beans still be put in sealed cans?

3. Do coffee in sealed cans need to be shaken every day?