Process for deploying different from redeploying?

Question

In the OC4J "Containers for J2EE" manual, in chapter 3, section "What Happens when you Deploy?", there is a "Note" that mentions if you deploy an EAR that is already deployed, then:
"the new deployment renames the EAR file prepended with an underscore. It does not copy over the EAR file. Instead, you can copy over the EAR file. OC4J notices the change in the timestamp and redeploys."
So does this mean that if you just want to deploy a new version of the application, you always have to undeploy beforehand? Do you have to check whether it is already deployed before you undeploy, or is it harmless to undeploy an application which is not deployed?

Answer 1

Hi David,
I can tell you how I deploy new versions of my applications. I'm not
saying it's the only way (and possibly not the best way), but it works
for me, and I'm satisfied with it (so far :-).
I am running stand-alone version 9.0.2.0.0 of OC4J on a SUN computer
with Solaris 7, and JDK 1.3.1
I always "undeploy" an application before deploying a new version of
that application. Undeploying involves the following steps:
(Note: Assume that the "name" of the application is "myApp" and I have
created a deployment file called "myApp.ear".)
1. Delete the "myApp.ear" file from directory
$OC4J_HOME/applications
where "$OC4J_HOME" is the root installation directory. On my SUN
computer, for example, this is
/home/aabrami/OC4J/j2ee/home
2. Delete the entire application subdirectory. Using my example,
the application subdirectory is:
$OC4J_HOME/applications/myApp
3. Delete the entire application subdirectory from the "application-deployments"
subdirectory. Again, using the above example, this is:
$OC4J_HOME/application-deployments/myApp
4. Remove the appropriate "application" element from the "server.xml"
file. That file is located in directory:
$OC4J_HOME/config
and the appropriate entry would look something like:
<application name="myApp" path="../applications/myApp.ear" auto-start="true" />
And that's it! Of-course, I have written a UNIX shell script that
does all this for me. The script file name is "clean". So basically,
in order to undeploy my application, I simply type the command:
clean
Again, I don't know how relevant the above is for your situation
(which you haven't told us much about ;-) but, hopefully, you will
get some use from it.
Good Luck,
Avi.