[GERONIMO-453] DerbySystemGBean doesn't call System.gc() in doStop() and soFail() as recommended in the Derby doco

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0-M4
• Fix Version/s: 1.0
• Assignee: Matt Richard Hogstrom
• Reporter: John Sisson
• Created: 08/Nov/04 00:40
• Updated: 07/Aug/06 15:05
• Resolved: 11/Nov/05 04:24

Description

The Derby doco in the section "Shutting Down the System" at http://incubator.apache.org/derby/manuals/develop/develop12.html says the following:

Typically, an application using an embedded Derby engine shuts down Derby just before shutting itself down.
However, an application can shut down Derby and later restart it in the same JVM session.
To restart Derby successfully, the JVM needs to unload org.apache.derby.jdbc.EmbeddedDriver,
so that it can reload it when it restarts Derby. (Loading the local driver starts Derby.)

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 Derby in the same JVM.

Anyone have any objections to the recommendation of calling System.gc()?