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Java Web Container implementation independant development

One of the most important non-functional requirements of any project is the build process in my opinion and that's where I kinda get stuck in my java project, which has just one external dependency, a jdbc compatible database. All the tutorials about spring and deployment out there; I've read them all, but they either say:
run it with gradle bootRun applications.properties (yes works but on a webserver I'm not going to have any properties-files, but JNDI resource for example) or
build a deployable war file with JNDI resources (yes it works on the webserver, but not in my embedded webserver or I'm doing it wrong, but I cannot find any doc about how an embedded tomcat loads a context.xml from outside the jar file).
Now I tried to use the same setup as my server and installed tomcat7 and the #Asyc #Scheduled services run, but no servlets, like a simple /status page should return "OK" just for checking. catalina.out does not show any errors. My /manager from tomcat7-admin says deployment ok, and when I click start: "FAIL - Application at context path /xyz-0.1.0 could not be started
FAIL - Encountered exception org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/xyz-0.1.0]]"
And now I want to make a cut here and throw every "bootstrap" stuff away and start from zero.
So my question is, am I wrong when I say, that the big deal of my deployment is a jdbc JNDI resource provided from the web container, which is called 'jdbc/xyz' and everyone who wants to deploy my war needs that JNDI. That means so matter if you're using wildfly, jboss, tomcat, glassfish or any embedded server: your server impl has to provide that web container and jndi resource to make it run. And I don't want to configure any tomcat, glassfish or whatever implementation in my war.
Is that wrong?
It would be great, if you could help me. I'm playing around with that many weeks now :( and if A works B does not and vice versa. Would it be easier to use JEE?
Thank you.

Still have Eclipse EE 404 on Mac after following advice on this issue

First of all, I am aware that there are other questions regarding Tomcat, Eclipse, and the infamous 404 error. However, none of them manages to resolve the issue. I have spent well over 24 hours on this issue.
To save time, when I configured everything (including Tomcat, and creating a server in Eclipse), I:
• Changed the server location from "workspace metadata" to its correct location by using the "Switch Location" button located in the server's Properties window.
• I chose the "Use Tomcat Installation" option in Server Locations, and saved the choice I made.
In both cases, I restarted the server. If you're curious as to what app I'm currently working on, it's a simple Hello World app, found at: http://theopentutorials.com/examples/java-ee/servlet/how-to-create-a-servlet-with-eclipse-and-tomcat/
• I have included the Java file in the "welcome file" list inside web.xml.
Lastly, out of curiosity, why does the Eclipse browser only go to the project directory, and not the servlet itself? (If I add on the servlet name, then "Hello World" appears).
• Yes, if I enter "http://localhost:8080", the default Tomcat page appears, so no issues there.
Can anyone clue me in, as to why I am still getting 404s after all this, and following advice that has been marked as "Accepted" here at SO, such as the following:
HTTP Status 404 - The requested resource (/) is not available
Thanks in advance for any help, it is greatly appreciated.

The error 404 may occur because of large amount of different reasons. In order to resolve that, you should check your tomcat log file out first. It contains by the path:
%PATH_TO_WORKSPACE%\.metadata\.plugins\org.eclipse.wst.server.core\tmp%SERVER_NUMBER%\
logs
Usually it contains some stacktraces which discribes the problem. If not, then you should check your deployed application out there:
%PATH_TO_WORKSPACE%\.metadata\.plugins\org.eclipse.wst.server.core\
tmp%SERVER_NUMBER%\___YOUR_APP____
It might happen that your application was not deployed correctly by eclipse plugin (happens very often) and you should try this:
Project --> clean
'Right click on your server' --> clean
Or just remove your webapp from the directory I mentioned erlier and redeploy it from scratch.

There is something basic you need to understand regarding using tomcat(or application server for that matter). There is a slight difference between using from Eclipse and using from outside
Using From within Eclipse
What happens here is that Eclipse (by default) uses a copy of your tomcat installation and places it in its metadata workplace. This secondary tomcat is used by Eclipse for all deployments, re-deployments and all. Keep in mind that this is not your original copy of tomcat installation.
The difference in this tomcat installation is that is actually a minimal server, meaning that although it has all the deployment capabilities, it does not have some of the extra features that come with the tomcat installation and one main feature is the tomcat's homepage (the only reason why people out there get the infamous 404 resource not found when they try to run-on-server their application).
Workaround
Although not an issue (nor a bug from the Apache's end), you can still view your application by changing the URL to your application's url, homepage or no homepage ! All you have to do is change the url from http://localhost:8080 to http://localhost:8080/yourApplicationName and voila , the default page of your application will be shown that you mentioned in the welcome-page-list. Keep note that if you didn't specify a default page in your web.xml, you will again wind up with, yet again, the dreaded 404 resource not found page. The reason is that Tomcat has found your application, but it doesn't know what to do at the root context of your application. You can either map your servlet to the root of the application (that way it will always run at http://localhost:8080/yourApplicationName) or you can change the URL to the url-pattern that you mapped with the servlet in the web.xml, it must be something like http://localhost:8080/myApplicationName/myServletMappingPattern

Easiest way to deploy web app to Apache Tomcat

I'm trying to deploy my first servlet to my server. There are, of course, many tutorials online. But most of them are very detailed and complicated, and I only need to deploy a few simply servlets to this server.
I found what I think to be the shortest method of deployment: Deployment on Tomcat Startup. I moved my .WAR file (FirstProject.war) into $CATALINA_BASE/webapps folder, but when trying to access it (ServerIP/FirstProject) I get the "The requested resource is not available." error.
Is there anything I forgot in the process of deployment?
I know that deployOnStartup has to be set to true, but I didn't change anything with the server's hosts, so the current host is localhost. I didn't change its settings, so deployOnStartup should be true (It's said that true is the default).
What am I missing?

You are using easiest way but I don't know what you are missing. Here what I would suggest is run your server and access through localhost:8080 then click manage app then enter username and password then you can deploy your war.
If you have any query post command.

Even i used to face this problem while deploying my first web application on Jboss and Apache ..
Even though your code is working properly with all your servlet mappings and paths using in your content files ...some times they kick back in real time environment ..So we have to know the proper deployment folder structure and accordingly we have to change our paths in the code
what i am concluding is check the below lines of code
Examples, assuming root is http://foo.com/site/
Absolute path, no matter where we are on the site
/foo.html
will refer to http://foo.com/site/foo.html
Relative path, assuming the containing link is located in http://foo.com/site/part1/bar.html
../part2/quux.html
will refer to http://foo.com/site/part2/quux.html
or
part2/blue.html
will refer to http://foo.com/site/part1/part2/blue.html

java.lang.NoClassDefFoundError: org/springframework/web/context/ContextCleanupListener

I have a webapp built using spring framework. I'm trying to deploy this to Tomcat6 using Eclipse. Everytime i make a change to jsp file, I had to clean the build, publish it & then start the server. I believe, we don't have to do all these steps for JSP changes. If i just publish the files, when the server is running, i get the below exceptions
SEVERE: Exception sending context destroyed event to listener instance of class org.springframework.web.context.ContextLoaderListener
java.lang.NoClassDefFoundError: org/springframework/web/context/ContextCleanupListener
SEVERE: Exception sending context destroyed event to listener instance of class org.springframework.web.util.Log4jConfigListener
java.lang.NoClassDefFoundError: org/springframework/util/Log4jConfigurer
And the war file is not getting deployed in server.
If I make a change to JSP file & then click restart in eclipse, it sometimes publish the files & then start the server. But in some cases, it restarts the server & then publishes the files (in which case i got the above mentioned exceptions & the war file was not getting deployed).
Ideal way that it works is, Stop the server, publish the contents & then start the server. I hate to do this every time i make a simple jsp change. Is there any alternate one click process to do this?

There's something wrong with the way you setup your project or server in Eclipse. I'd recommend following the instructions here. Also, you may want to download STS (Eclipse already bundled with Spring support) and use that instead of the vanilla eclipse.

Make sure that spring is deployed together with your application. Either set the correct export options in eclipse or copy the spring libraries to /WEB-INF/lib.
MyEclipse works fine here. You could also check JRebel as well. They advertise no redeployments. ;)

you can use exploded war and incremental hot-deploy.
this should work http://www.youtube.com/watch?v=OMtcjgTyP-g
folow at 2:30

modifying the jdbc.properties file for a Tomcat webapp

I am trying to point a Tomcat webapp from one Oracle database to another. To do so, I navigated to the webapps/[my web app]/WEB-INF/classes folder, and I edited the jdbc.properties file so as to change the connection URL, user, and password.
As soon as I did this, the webapp failed to work (it was working before). I end up getting Apache Tomcat error 404 - "The requested resource [my web app] is not available".
I know that the connection URL along with the user/password combo work perfectly fine, as I have tested it in SQL clients. Does anyone know why my webapp failed to work after my modifications? Are there any other modifications that I have to make?