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Modular jars/plugins within a Wildfly Web Application using ServiceLoaders

We extensively use Java ServiceLoaders as a plugin infrastructure for our application components. We define interfaces, and then use the loader to load them at run time. Adding additional jars with extensions and service files are fine for our use cases.
However, i'm struggling to understand how we would be able to continue this approach while deploying an application within Wildfly. The intent is as stated above, the ability to add "extension" jars to the web-application class path without having to
Stop the server
Unzip the war
Add additional jar
Zip war
Start the server
In Tomcat, we could deploy web application folders instead of a war. So stopping the server, dropping in a jar, and starting the server worked fine. Within Wildfly (latest), it appears to not like the deployment of a folder vs war.
I've read about the modules approach, but have not been successful using this approach to get the deployed application to see the module from the service loader implementations.
Would like to know if there is an alternative solution or perhaps we are doing something wrong?
Thanks

WildFly supports exploded deployments with the deployment scanner or using the explode command with jboss-cli. Using the jboss-cli you can even update files remotely.

How to access beans loaded in common jar in different web applications deployed in tomcat

I'd like to know the best way to load shared jars into Tomcat so that two or more WAR's deployed in Tomcat are able to access Spring Beans from common jars without any issues.
When I'm deploying more than one WAR into Tomcat, beans in common jars are getting overwritten every time an application is deployed. How can I configure or load common jars that every application deployed in Tomcat gets its own set of beans without overwriting any other application beans.
I'm loading common jars from shared path.. Tomcat loads jar from its lib directory, then from shared location then from WEB-INF/lib[.war] and so on... My Question here is, how to load jars which are shared between multiple web applications. I also wanna ensure that spring beans loaded in one application context are isolated from others.

I am not sure whether I understand your meaning. In java web, the jars are loaded by class loader based on some strategy. If your jars are in lib directory of tomcat, every application deployed in this tomcat can load these jars from tomcat lib directory.
And if the jars are in your war packages, every application will load from it own war package.
In the normal, we will not put any jars into tomcat lib by ourselves.

How to Deploy Java EE Project which reference external JAR files in weblogic

I have a web application which consist of JSP pages, Servlet and Consumes Web Services.
It also references apache axis and excel libraries.
Now I want to deploy my application directly in Weblogic server
How do i do that.Whcih archive shud i make WAR or JAR??
ALso how to ensures that it covers all the referenced libraries.
I have made my application in Jdeveloper, but I dont want to deploy it using Jdevelper..

I would package my solution as a .war file, containing all dependent .jar files.
That way your solution is self-contained. You can deploy to an app server containing other apps with their own versions of your libraries (dependent or developed). If you put the dependent jars directly into the app server (as you can do), then you're forcing those versions on all applications deployed, and that could well cause you grief.
The downside is that your developed .war file can become sizable. It's not normally a major problem, and I wouldn't worry about it until it's identified as an issue.

A JAR-file cannot contain a JAR-file, so that option is out. Since you mention JSPs and servlets a WAR would seem the appropriate option, although an EAR with a WAR and several JARs could also be a way forward...
Cheers,

Consider a WAR with your JAR files in WEB-INF/lib. Or, create an EAR with APP-INF/lib folder.

Webapp not deploying in glassfish when I have jars in the modules folder

I have a Spring webapp running in Glassfish 3.1.2. I am just beginning to convert the webapp to OSGi. I undeployed the existing webapp and copied the spring and gemini OSGi jars into the modules directory in the Glassfish installation. I then installed and activated them using the Glassfish OSGi web console (which I understand to be some sort of customised Felix web console) and everything was fine. It didn't do anything but I could install and activate them in the web console which is what I wanted to test.
I then started to redeploy the non-OSGi jars of my existing webapp using the Glassfish Application console to see if the 2 type of jars could coexist, which, given my understanding of OSGi I thought they should be able to. At this point NoClassDefFoundErrors started getting thrown complaining about not being able to find org.apache.commons.logging amongst other classes. These class were present in both the Module directory as the installed OSGi jars and the application classpath. I then deactivated the jars in the console but didn't remove the the OSGi jars but the exceptions continued to be thrown.
I got a classloader print out and found that the jars in the WEB-INF of my webapp weren't getting loaded but I wasn't sure whether this was the problem or a symptom.
I then removed the jars from the uninstalled the OSGi jars and everything started working again and the webapp could be deployed.
Can anyone think of any reason why this might happen? I am guessing that the content of the module directory is on the classpath but if so why? How would I prevent this from causing problems if I want OSGi and non-OSGi jars to work together?
Side Notes
When I viewed the classes getting loaded by the classloader I couldn't see content form the modules folder getting loaded.
I can install and activate the OSGi jars after the the non-OSGi jars are deployed but not the other way round.

( Disclaimer: I do not have specific experience with glassfish, but JBoss and other
strange environments sporting classloader hierarchies)
You have to be carefull with classloader hierarchies in java - the same bytecode equal class will not be equal or asignable to if comes from another classloader, and while loading classes it is important to find dependencies through loading classloader or his parents.
To resolve your situation you will have to carefully examine this hierarchy and check settings for delegation and class resolution ( like parent first / self first ).
JBoss tried to solve this problem by introducing unified classloader which resulted in one big pile of assorted classes and leaks of resources between contexts / webapps in default setting.

When releasing a java spring web application, what are the steps to deploy/release?

If I make a spring mvc application, what are the things I have to do to deploy the application? (say its a commercial application)
What options do I have? Do all applications compress the classes into a .war file?
/WEB-INF/web.xml, appname-servlet.xml, etc.
/WEB-INF/jsp/*.*
/WEB-INF/appname.war ???

Done correctly, the build process will create a war which can be dropped into any servlet container (Tomcat, Jetty, Glassfish).
If you use external source files, those would have to be configured.
If you use advanced features provided by the servlet container, the server would have to configured as well.

Spring application is no different from any java web application when deploying. but generally the only thing I have to do is flip the order of test spring config with the actual one.

Any IDE could create the WAR file for you. As you've said the configuration xml files go to /WEB-INF folder and jsp files (by default) to /WEB-INF/jsp/. You also need to put all required jar files in /WEB-INF/lib folder. Compiled classes will go to /WEB-INF/classes, but let the IDE do that for you.
The war file shouldn't be in the /WEB-INF folder. In Tomcat for example you need to copy it to the webapps folder.