mod_jserv/5057: output stream closed during a re-direct to a servlet

[Matthew King <mk...@district.vannet.k12.wa.us>]

>Number:         5057
>Category:       mod_jserv
>Synopsis:       output stream closed during a re-direct to a servlet
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    jserv
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Wed Sep 22 16:20:02 PDT 1999
>Last-Modified:
>Originator:     mking@district.vannet.k12.wa.us
>Organization:
apache
>Release:        Apache 1.3.6 Jserv 1.0
>Environment:
Windows 98
JDK 1.1.8
JSDK 2.0 and 2.1
>Description:
When performing a sendRedirect() from one servlet to another, calling out.flush()
causes the output stream to close.  

I was using the flush command to allow the parent class to write information at
the top of every page produced by the child classes.  This worked fine in normal
(ie GET, POST, etc) operations.  However, when the child class received a 
redirect, the call to flush() closes the output stream after writing.
>How-To-Repeat:
To replicate it, put a call to out.flush() in the middle of either doGet() or
doPost().  Example:

out.println ("Hello");
out.flush();
out.println ("Goodbye");

During normal operations, this will simply write "Hello" to the browser, followed
by "Goodbye" (demonstrating that the flush() did not close the output stream. 

During a redirect, it will write "Hello" and then close the output stream.  
"Goodbye" will never appear.

I can also send a pair of example servlets that show this problem, if you like.
>Fix:
The redirect should wait until a close() is received, or the specific number of 
bytes in setContentLength() are received.
>Audit-Trail:
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