If the application that started the embedded quits but leaves the 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:

Shutdown commands always raise SQLExceptions.

When a system shuts down, a message goes to the error log:

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 JVM needs to unload org.apache.derby.jdbc.EmbeddedDriver, so that it can reload it when it restarts . (Loading the local driver starts .)

You cannot explicitly request that the JVM unload a class, but you can ensure that the EmbeddedDriver class is unloaded by using a System.gc() to force it to garbage collect classes that are no longer needed. Running with -nogc or -noclassgc definitely prevents the class from being unloaded and makes you unable to restart in the same JVM.

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.