On 7/11/2012 10:14 PM, Matthew Hauck wrote:
I am writing about the well known error: "Failed to start database
'...' with class loader ..." I realize that you cannot have two
simultaneous connections from two different JVMs to a derby embedded
database. My question is whether or not it is possible to disconnect /
"unload" / "unboot" one connection in order to load up the other one,
etc. Or does the first JVM have to entirely stop before the next one
can make a connection?
I ask for TDD reasons. One of the tests I'm trying to write (on
cucumber / jruby) requires some out-of-process testing. i.e. I have
one process (cucumber) invoking the tests, which requires the spawning
of another process. I would like the parent process to be able to turn
off its connection to the embedded database (without shutting down),
such that it can allow the spawned process to access the database, and
then turn it back on and make sure things went as planned after the
other process completes.
Is this possible?
You can shutdown a single database without exiting the JVM using the
shudown=true attribute if using a DriverManager connection:
http://db.apache.org/derby/docs/10.9/ref/rrefattrib16471.html
or with the DataSource property shutdownDatabase()
http://db.apache.org/derby/docs/10.9/publishedapi/jdbc4/org/apache/derby/jdbc/EmbeddedDataSource40.html
This will allow another jvm to boot the database. Then then after the
spawned process completes, first jvm can reconnect which will reboot
the database.
Best
Kathey
