If the application that started the embedded quits
but leaves the Java Virtual Machine (JVM) running, continues
to run and is available for database connections.
In an embedded system,
the application shuts down the system
by issuing the following JDBC call:
DriverManager.getConnection("jdbc:derby:;shutdown=true");Shutdown
commands always raise SQLExceptions.
When a system
shuts down, a message goes to the log file:
----------------------------------------------------------------
Wed Mar 02 17:08:36 EST 2011: Shutting down Derby engine
----------------------------------------------------------------
Wed Mar 02 17:08:36 EST 2011:
Shutting down instance a816c00e-012e-789c-116d-000000bbdd88 on
database directory C:\sampledb with class loader
sun.misc.Launcher$AppClassLoader@11b86e7
----------------------------------------------------------------
Typically,
an application using an embedded engine
shuts down just before
shutting itself down. However, an application can shut down and
later restart it in the same JVM session. To restart successfully,
the application needs to reload org.apache.derby.jdbc.EmbeddedDriver as
follows:
Class.forName(org.apache.derby.jdbc.EmbeddedDriver).newInstance();
Loading the embedded driver starts
.
The JDBC specification does not recommend calling
newInstance(), but adding a newInstance() call
guarantees that will be
booted on any JVM.
If your application will need to restart
, you can add the
attribute deregister=false to the connection URL to avoid having to
reload the embedded driver:
DriverManager.getConnection("jdbc:derby:;shutdown=true;deregister=false");
It is also possible to shut down a single database instead of the entire system. See .
You can reboot a database in the same session
after shutting it down.