Installing the mod_jserv Java Servlet Module for Apache.

Installing mod_jserv Dynamic Module

The mod_jserv Dynamic Module is a 100% pure Java servlet engine fully compliant with the JavaSoft Java Servlet API 2.0 specification.

NOTE: This Apache module is an older bridge between Java and Apache. On FreeBSD Virtual Servers this used to incorportate all the heavy parsing and so forth of JavaServer Pages as well.

On Solaris, this module runs unmodified and talks to the Jakarta Tomcat Server if it is available, but is not as fast (and is no longer supported by the Java Apache group) as the mod_jk Apache Module. For those who are migrating a lot of FreeBSD JavaServer Pages to Solaris, this might be a good solution until they can use the mod_jk module.

NOTE: The Java servlet engine can often be very memory-intensive. For this reason it is recommended that it be used on a Virtual Server C.

Installation
Connect to your Virtual Server via Telnet or SSH and do the following.

Issue the command below to install mod_jserv.

% vinstall mod_jserv
Using your favorite UNIX editor find the following line in your ~/www/conf/httpd.conf file and uncomment it to enable mod_jserv. To uncomment the line, remove the "#" character.

#LoadModule jserv_module /usr/local/etc/httpd/modules/mod_jserv.so
Finally, run restart_apache to reload your config file.

% restart_apache

Is mod_jserv Running?
At this point, if you run the top program you should see the Java servlet engine running. The output to top will look something like below. The line with the COMMAND java is the Java servlet engine.

last pid: 24593;  load averages:  0.00,  0.01,  0.00   up 10+04:48:51  20:10:25
11 processes:  1 running, 10 sleeping
CPU states:  0.4% user,  0.0% nice,  1.5% system,  0.0% interrupt, 98.1% idle
Mem: 18M Active, 160M Inact, 24M Wired, 6304K Cache, 8273K Buf, 29M Free
Swap: 512M Total, 512M Free

  PID USERNAME PRI NICE  SIZE    RES STATE  C   TIME   WCPU    CPU COMMAND
24593 biff      28   0  1500K   720K CPU1   1   0:00  3.08%  0.29% top
24192 biff      18   0 20676K  3240K pause  0   0:47  0.00%  0.00% java
24185 biff      10   0  2108K  1300K nanslp 1   0:01  0.00%  0.00% httpsd
24181 biff      18   0  2156K  1384K pause  0   0:00  0.00%  0.00% httpsd
24590 biff      18   0  1304K   964K pause  0   0:00  0.00%  0.00% tcsh

You can also check to see if the Java servlet engine is running by trying this URL.

YOUR-DOMAIN.NAME

If you see the following message in your browser then it is installed and running correctly.

Example Apache JServ Servlet

Congratulations, ApacheJServ 1.1 is working!

If you don't get the above message then check your error_log file and try enabling Apache Jserv logging by editing the following line in your ~/www/conf/jserv/jserv.properties file to read true instead of false.

log=false

You may also try adding the "Debug log channel" by adding the following to your jserv.properties file.

log.channel.debug=true

NOTE: Logging can be a very expensive operation in terms of performance. You should turn logging off as soon as you correct the problem you are diagnosing.

More Information
For more information, see the Apache JServ Project

SEE ALSO:

Installing mod_jk

About Java

Java Servlets

Virtual Server Configuration

About the Apache Web Server

BOOKS TO HELP YOU:

Writing Apache Modules with
Perl and C