Experts
When we redeploy any application from an IDE such as MYEclipse , it just redeploys the .class files. I want to customize the eclipse developer, so the deployer can also deploy the custom files (other than class files).
Should i write any custom ANT script for Myeclipse or any custom settings the My Eclipse provides us ?
IDEs along the classes and libraries usually deploy everything they find in the web / www-root folder (in the folder that contains the WEB-INF and META-INF).
So you can configure your deployed applications structure using the IDE by structuring the content of that folder.
If it still doesn't fit your needs, then ANT would be the best option.
In my opinion ANT is always the best option, but using the development environment's functionality is proven faster then writing an ant build file.
Say, if you're developing a web service, a web application consuming that service, and a library that both the service and the webapp uses, then with a single (and not even long or difficult) ant file you can build them, create the aar, war and jar files and deploy them all in their correct places, eg. under axis, inside the global lib folder, and in the webapps folder.
All these in one step.
Related
I have a Java EE web application written in Eclipse and deployed on WebLogic.
When I deploy it from Eclipse (as a virtual application) it works fine. When I try to create an EAR file and deploy it from the WebLogic console I get a ClassNotFoundException.
What could be the reason?
How can I create an EAR file that will match the structure of the virtual application so it will work?
Usually this means a dependent library is not being deployed. This tends to be where Eclipse has a dependency which it fulfills as part of the internal build. When building it yourself, work out which libraries you need, and which are part of your application, and which are part of WebLogic. For your own libraries (ie those in the lib folders, or those that SHOULD be in the lib folder) make sure they are on the classpath. For external libraries, ie those WebLogic fulfills, make sure you have the appropriate schema descriptors setup to tell weblogic which libraries it needs to deploy with your application (typically things like JSF).
If you want proper control over the build, take a look at things like Ant. You basically tell it via xml what is needed, put it together, and it generates the Ear/Jar file for you (the Ear file containing all the dependencies as well, and/or with your descriptors for weblogic built in libraries).
If you are planning many builds, I find Ant useful once setup (you can tie it in with other programs too, so it can push a build to your Source Control Server as a tag, build documentation, etc). Ant can be a pain though- you need build descriptors for each library you need to build, as well as the Ear file.
Eclipse's Web Tools Platform (WTP) allows you to configure Tomcat to "Server modules without publishing":
Web content will be served directly from the "WebContent" folder of the Dynamic Web Project. A customized context is used to make the project's dependencies available in the Web application's classloader.
In a 5 step process (just joking, you pick the # of steps), what happens technically and where are the files that Eclipse generates? I did notice that Eclipse generated a org.eclipse.jst.server.tomcat.runtime.70.loader.jar file in the Tomcat lib directory.
The idea is to serve a web application directly from the scattered directory structure of the development workspace, without packaging modules into JARs which then end up in WEB-INF/lib in a WAR.
The main benefits are:
You don't need to build archives.
When you change a resource in your workspace, the change is reflected in the running webapp without redeploying the webapp or restarting the server.
With Servlet 3.0, web resources may also be bundled in library JARs in META-INF/resources, so classes and resources may come from multiple workspace directories.
Tomcat 7.0 supports a VirtualWebappLoader and a VirtualDirContext to configure a web application based on a collection of scattered resource and class directories.
To serve your web app directly from your Eclipse workspace, WTP generates a suitable Tomcat configuration matching your project structure
in $WORKSPACE/.metadata/.plugins/org.eclipse.wst.server.core/tmp1/conf/server.xml
For some reason, WTP does not directly use the Tomcat loader and context implementations but has its own WtpDirContext and WtpWebappLoader which are slightly different but similar. (I believe this approach is older than the current solution in Tomcat. There is some special logic for TLD scanning - I'm not sure if this is still required with the latest Tomcat versions.) These helper classes are contained in the org.eclipse.jst.server.tomcat.runtime.70.loader.jar you noticed.
Without Serve modules without publishing, when you change a web resource in META-INF/resources in a library module, this change will not be directly visible in the running application after reloading the current page in the browser.
I'm having a hard time getting JRebel to work in my current development environment.
I have multi module maven projects. Currently, the Tomcat instance is controlled via service (tomcat monitor) and the deployed web apps are configured with a XML located at ${catalina.home}/conf/Catalina/localhost where the docBase attribute points ${absolute maven project path}/target/app (and the attribute reloadable is true). So every time I do a maven build I only have to manually restart tomcat if there any classes changed. If the modifications occurred in the static resources (JSP, HTML, JS,
etc..) a page refresh will do it.
On my first attempt, I configured the web apps to run on a tomcat server running inside Eclipse. The maven plugin provided was also configured with success: all my sub-modules inherited the plugin configuration and I can saw in the tomcat startup the output messages from JRebel indicating the absolute project paths that were been listen. The only problem is that Eclipse WTP / Tomcat plugins don't go weel with War overlay feature in eclipse. After starting the server, only the resources present in the last web app (the module that have other War as dependencies) were deployed.
So, I returned to my original configuration development and introduced JRebel to it. I passed the JRebel java options to the Tomcat Vm, all maven modules had the rebel.xml (listening to the correct resource folders), but nothing happens. I can't see the usual JRebel messages and I experimented changing a JSP in the source folder and do a page refresh but the file ins't automatically redeployed (in this case a simple copy from the source folder the the ${maven.projec}/target/app will do the trick).
My two questions are:
It's possible to over come that eclipse WTP issue?
What is a funcional development environment involving maven eclipse and a external tomcat?
Any help would be much appreciated!
UPDATE 1
So, I got it. Kind of...I'm still struggling with the war modules overlaying. I have a main web app module that depends on several webapps modules. Because the rebel.xml it's generated dynamically via jrebel maven plugin when the main webapp build occurs, only the it's jrebel.xml prevail. All the other are squashed. The rebel.xml for the jars modules are at the right places (inside the jar file).
I can get it work if I create a custom rebel.xml for the main webapp that points to all the absolute directories containing the source files (static files such as JSP, HTML, JS, CSS, images, etc.) of the depending web apps. But this is worthless for my team development environments. I'm using maven properties but we've have two different maven multi-module hierarchy that don't know about each other and I can't use a root pom to connect them. So these kind of properties will not be enough to guarantee that the absolute paths generated on each developer machine in the rebel.xml are correct.
For now, I'm trying to tackle using some kind of maven plugin to do the rebel.xml merge. For the record without success yet.
This is becoming another issue a bit different of the original question :) Maybe I should through another question.
UPDATE 2
I got it working!..finally.
I used the XSLT Generator Maven Plugin to help me merge the various rebel.xml files. Also had to use the fabulous Maven Copy Plugin because the xslt transformation occurred after the final war packaging and I had to add the resulting rebel.xml to that WAR.
If someone needs the configuration files details down't hesitate asking.
Hope's this helps someone out there.
I got it working!..finally. I used the XSLT Generator Maven Plugin to help me merge the various rebel.xml files. Also had to use the fabulous Maven Copy Plugin because the xslt transformation occurred after the final war packaging and I had to add the resulting rebel.xml to that WAR.
So far i've been using tomcat and glassfish to develop a testing webapp, without maven. And the usual development-till-deploy cycle is simple :
develop in eclipse ide, with a WebContent folder, which is the root webapp folder that has the WEB-INF, web.xml, WEB-INF/lib, n all. The compiled classes location in eclipse is set to WEB-INF/classes.
after coding, i could just click on the reload button in glassfish admin console for that specific webapp. In tomcat, i believe it's reload also in the tomcat manager.
i could access the web application in the browser
Now if i would like to create a new webapp, that'll make use of latest stuffs of jsf, spring, jpa, hibernate, postgresql :
what recommendation of archetype should i use in the creation of the project ?
can i still use my previous steps of development? because i think it's very easy without having to repackage everything into a war file, or copying it into the tomcat's webapp folder everytime i want to test. Saving the files in eclipse, hit on the reload in the admin console / tomcat manager, and i could instantly test the updated webapp.
Or what do you usually do in the webapp development cycle ? Please share your experiences, =)
Thank you !
Development Cycle with Maven and Friends
Use Maven to drive your code-build-test-deploy-release cycle.
Start with Maven Archetype that suits closest to your web-app. This will create the whole folder structure for you and will add Jar depencies.
Use an embeded light-weight server like Jetty, this will be very fast on dev machine without sucking resources and is highly configurable. Plus, you can set it to auto-reload changes.
Most of Maven project are supposed to be test-driven. Of which Maven takes care of using it's surefire plug-in. So, every build will have a test phase.
You can define multiple profile for various environments (test, dev, prod, Win, Unix..). These profile will alter the behaviour of the project to be compatible with the environment.
Use Cargo, again a Maven plugin to deploy your builds on test or production server, which can be Glassfish, Tomcat, Jetty or any oter webserver.
Use Liquibase with or without Maven :) to manage your database changes the same way you manage your code change.
I came from almost similar project as yours in my previous company. Development with Maven makes things so smooth and the change is appreciable.
A little Google search shows that someone has worked on archetypes for JSF and JPA with Spring
Edit#1 -- added more details
Feasibility and Ease of Use
Maven is born out of neccessity to simplify the dev process for large and distributed code.
Maven is very well integrated with Eclipse -- so it's painless.
Jetty keeps monitoring source folders, so your changes gets deployed almost immediately.
You can customize the build to skip tests, to not build dependecies. When you just edit a UI component, Jetty will silently copy it to "target" folder.
If you're worried about copying and redeploying. You must read THIS to see how efficiently things are done, keeping in mind that you don't have to compile-test-deploy everytime you change a JSP or HTML.
That said, I would like to mention that Maven might be a challanging learning. This is an object oriented way of development cycle, to say. Most of us, who are used to build script, can find a bit tedious/verbose initially.
Resources
I would suggest to go through the following resources
Maven Book - Maven basics
Automated Deployment with Maven - going the whole nine yards If you can, literally follow this pattern.
Maven 2 Effective Implementation -- this book really helped us a lot.
for the q2 :
You can still run/debug app with tomcat from within the IDE (eclipse) even if you change the directory structure. (like the maven dir structure instead of eclipse's dynamic web dir structure)
Project properties - >
project facets - >
Dynamic Web Module ->
Click the appearing "further configuration available"
and set your content dir and context root.
You dont have to package everytime you want to run/debug it.
Another option is using Jetty
And I am sure there are more options others will tell as well.
I have a Java web app that offloads some environment specific settings (Hibernate configurations, required directory paths, etc.) in a properties file that is ultimately packaged in the deployed WAR. If I wish to distribute this web app, what's the best way to handle the mangement of these settings? It's not feasible to ask the user to open up the WAR, update the properties file, repackage the WAR, and then deploy. I was thinking of either creating an installer (e.g. NSIS, WiX) that asks for the properties, writes them in the WAR, and then asks for the deployment location for the WAR. The other option is to have the properties file external to the WAR, and based on convention the web app will know where to read the file. What's the best practice in this case?
Some projects that require this sort of configuration, and face this issue, use the approach of building the projects (and the .war) on the server where it will be deployed.
So instead of:
Copy a pre-packaged .war file to a meaningful location
You get:
Check source code out of SCM (Subversion, CVS, etc.)
Configure to taste
Build the project (automated with Maven or Ant)
Deploy the project (also typically automated using Maven or Ant)
From here you can get fancy by checking each server's configuration files into SCM as well. This approach allows you to version & audit configuration changes.
I was also facing the same problem in the project. The developer before me had done crude fix for the solution which was adding all the required configuration in the hibernate.hbm.cfg.xml file and commenting them. The required configurations were uncommented as per the need. There is a better solution to problem however.
Use a configuration folder schema
Using configuration Parameter Reader
Use of ConfigurationReader component
Source : http://www.javaworld.com/javaworld/jw-11-2004/jw-1108-config.html