mod_jserv/5117: Servlet's destroy method does not appear to be called on server restart or stop

[Peter Santoro <pe...@pscomp.com>]

>Number:         5117
>Category:       mod_jserv
>Synopsis:       Servlet's destroy method does not appear to be called on server restart or stop
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    jserv
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Sat Oct  9 06:20:01 PDT 1999
>Last-Modified:
>Originator:     peter@pscomp.com
>Organization:
apache
>Release:        1.3.6
>Environment:
Apache 1.3.6 and JServ 1.0
RedHat Linux 6.0 with updates and kernel 2.2.12
JSDK 2.0 and JDK 1.17B
>Description:
It appears that a servlet's destroy method is only called when the ServletManager
re-initializes a servlet.  I've verified this using the log() API call and have
also tried to write to my own log file.  This is not serious for simple servlets, but
is more of a concern for servlets that rely on using cached resources to improve
performance or want to save state before being destroyed.  Looking through the bug
database suggests that this problem may have been around as early as 1.3.4, but
it is not documented as such.

Further testing shows that destroy() is called when you update the servlet's
class file when autoreload.classes=true.
>How-To-Repeat:
Make sure autoreload.classes=true in zone file.

Add init() and destroy() methods to Hello.java example.  Add a log() call to
the init() and destroy() methods, recompile, and run servlet from browser.
View log file to see init's log() message.  Restart and/or stop Apache.
View log again and message from destroy is NOT in the log.

Re-run servlet from browser and see init's log() message in log file.  Recompile
Hello.java and re-run servlet from browser.  View log to see that destroy() is
called a few messages after the "Re-initing ServletManager servlet" message.
>Fix:
If the destroy method is really being called on server start or restart,
perhaps the log needs to be flushed.  However, the fact that I cannot write to
my own log file suggests that this may not be the case.

Perhaps this is a timing issue?
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