java.sql.SQLException: database locked

Answer 1

It seems that more than process is trying to modify the database. You can have only connection open at any given time. More background of the problem may help us provided you with a more concrete answer.

Answer 2

Reading an SQLite database sets the locking state to Shared. Multiple readers can be active at the same time.

Writing to an SQLite database sets the locking state to Exclusive. No other processes can be active at that time.

You can find a detailed explanation on http://www.sqlite.org/lockingv3.html