JDK 1.5 installation

[stuthemonkey]

I have gotten a vps with plesk 8.1 installed on it. And I noticed that the tomcat plugin for it is a tomcat 5.0 setup, which is fine. However it only runs jdk 1.4.2. My question is, if I were to install jdk 1.5.x onto the linux machine, would that break anything in plesk? Does anything it does use the jdk that is installed, that it couldn't do with 1.5?

I would be installing it along side 1.4, and not overwriting it, so that shouldn't be a problem, and I just won't change the java_home environment variable. and then just setup the tomcat.conf files to point to the location of the jdk 1.5. But does anyone know of any reasons why this wouldn't work? Or have any trouble experiences they want to share about doing this?

Thanks for the help.

 

[stuthemonkey]

Does anyone have any suggestions about getting jdk 1.5 to run with plesk? is it as simple as installing the jdk 1.5 rpm in a secondary location to the 1.4.2 that plesk installed, and pointing tomcat to use it instead?

I've looked all over the net and have not been able to find any information on this. And my host says that if swsoft doesn't have any info, they won't help me either.

I would hope that now that jdk 1.6 is out, that 1.5 will soon be supported, but who knows.

 

[garan]

There's no issues with Tomcat when it comes to having multiple version of the JDK on a box. Setting the JAVA_HOME variable within the startup script to point at a specific JDK directory isn't difficult and Tomcat will obey. RPMs are the easiest way to install.

If you're running other Java tools on the box though (scripts for example that call 'java') then you will need to be more careful. On most linux distributions I've come across recently there is a /etc/alternatives directory. Something like /usr/bin/java will be a symlink to /etc/alternatives/java which will in turn point to a specific java binary. If you're looking to globally change the java version on the box you have to be a lot more careful. But as I said above this isn't needed just to update the JDK that Tomcat references.

If you're looking to update Tomcat from 5.0 to 5.5 then you may be interested in this post

http://forum.swsoft.com/showthread.php?s=&postid=162498#post162498

Cheers,

Garan.

 

[stuthemonkey]

Garan,
Thanks for the response. I knew that resetting the java_home globally on the box could potentially be an issue with other things that run java on the box, which is nothing that I know of, except anything internal to plesk. Which I believe after some research is only the ssh client through the plesk admin interface. Thats why I thought I would do the install of jdk 1.5 somewhere different then the 1.4 install that plesk is currently using. And then pointing tomcat itself to that, so anything that runs java wise outside of tomcat could still use the other jdk just in case 1.5 would break it.

Thank you for reconfirming my thoughts, and I now believe this is quite do-able. Although my host says not to, since plesk doesn't say they support it yet. and all of that. but if I leave the one plesk supports there, and only point tomcat to the new one there should be no issues.

Thank you also for pointing out the post to how to get tomcat 5.5 to run. I don't need this one yet, but I probably will sooner or later.

Thanks again
trolli

 

[CiViX]

I asked SW-soft about this sometime ago, and they answered:

1) Is it possible to upgrade to Java 1.5.0? Will this break Tomcat/PLESK in any way?

Currently Plesk only support Tomcat version <=5.5 and you can read from tomcat 5.5 release notes that ( http://tomcat.apache.org/tomcat-5.5-doc/RELEASE-NOTES.txt ):

Tomcat 5.5 is designed to run on J2SE 5.0 and later, and requires configuration to run on J2SE 1.4.

So upgrading Java will break Tomcat definitely. Plesk will work properly in this case, of course apart from tomcat management.

Next tomcat version support will be implemented in next plesk releases (I do not know when currently and cannot provide you with any ETA)