Couchbase is a NOSQL persistent data store. You can store Serializable Java objects in couchbase.
I have used Couchbase extensively to save all the configurations properties. I have saved all the properties as JSON objects. These objects can be created and edited directly using the admin console provided by Couchbase.
You can perform asynchronous get/set operations with couchbase.
I have observed that the get/set operations fail at certain times. Hence, I have also implemented retrying mechanism. In the retry mechanism I add the the failed tasks to a List of pending tasks. I perform the get/set operations of these pending tasks by means of a separate Timer task which is scheduled at a regular interval.