RecordStore

rms.list — List available record store names, or id's for a name.
rms.size — Returns the size occupied by the record store
rms.sizeavail — Returns the amount of space available to grow for this record store.
rms.set — Sets the value of a record store
rms.get — Fetch the value of the specified record store and record id
rms.add — Adds data to the specified record store, returning the new record id.
rms.delete — Deletes either the record store, or a record id associated with a record store.
rms.hset — Sets a key/value pair in the given record store.
rms.hget — Gets the value of a given key in the specified record store
rms.hexists — Determine whether a given key exists in a record store.
rms.hkeys — Returns all keys associated with a given record store.
rms.hdel — Deletes a key from the specified record store.

Record Store is the name for persistent storage in J2ME. Even simple MIDP1.0 phones have this feature, and utilize it to store data between invocations of the application.