Spring Rest Controllers: deployment to Tomcat - spring

I want to develop a RESTful API within my multi-module Spring-based project using Spring Rest. For that purpose, I have a webapp module and some other business/data layer modules. For example, this would be my simplified project structure:
myProject
-- webapp (war-packaged)
-- business (jar-packaged)
-- data (jar-packaged)
Business module depends on data module and so does webapp on business module. Webapp imports successfully every module's application context. Now I want to be able to use some business module classes that do some kind of calculation according to some data retrieved from a DB in order to provide a certain resource. All examples I had a look at were quite simple and this multi-module approach was not covered at all.
What is the problem? As far as I am concerned, Tomcat loads classes in a certain order. Concretely, it first loads WEB-INF/classes and only then WEB-INF/lib (where all webapp dependencies are placed, business module in this case). So, there goes my question. Where should I place my Controller classes? If I place them within the webapp module I won't be able to autowire any business-module bean since Tomcat will throw a ClassNotFoundException when I deploy the webapp war (at least this is the behaviour I have experienced).
The answer is probably easy but I'm quite new to Spring and its world!
Thank you all in advance.

Your business and data jars would go into the WEB-INF/lib directory. Then those jars will automatically be added to the CLASSPATH for your app when you deploy it. You will need to deploy your application as a WAR file.
Ideally, you would build the business and data jars, add them to some repository, and then the build system would pull the proper version of each jar into the WEB-INF/lib directory for you.
And as to the original question, the controller classes go into the webapp/src directory.

Assuming you are using Maven 2. Make sure your assembly creator (e.g. maven war module) is including your dependent .jar files within the final .war file's WEB-INF/lib directory. This should be the default procedure (per: http://maven.apache.org/plugins/maven-war-plugin/war-mojo.html#dependentWarIncludes ). The other concern, then is whether your sub-projects (business and data) are even creating jars so that they could be included in the WAR output.
If you have doubts as to the contents of that war file, browse the listing of it by executing
'jar tvf $WAR_FILENAME' from the command line and by observing the WEB-INF/lib directory contents. You should see your business and data jars in there. Go further by exploding your war file, then browsing the contents of business and data jar (using 'jar xvf $FILENAME' to explode in a new directory).
Hope this helps!

Related

cannot find service.jar file custom portlet liferay

I am using liferay 6.2 & built a maven portlet and working fine, I want to use its tables to store data for another portlet so that I need its services in this portlet.
But we can't access it externally so i find a way something like: required-deployment-contexts=Portlet-Project1 inside liferay-plugin-package.properties, then found its works for Ant only.
I was also finding the xxx-portlet-service.jar but didn't able to, so that i could manually put it in other portlet's lib folder i.e inside tomcat-webapps-xxxportlet-WEB-INF.
Just want to find how to use xxxLocalService.util in other in maven portlet
The best approach you can implement is a plugin to manage all the interaction with the DB.
First of all you must create a Service with a maven project and include it into your pom.xml in each portlet that you need. Then you can invoke its methods whenever you want because each portlet will store the dependencies.
Create Service Plugin into jar file
Rebuild with mvn clean liferay:build-service
Custom your own methods to manage the iteraction with the DB (LocalServiceUtilImpl and rebuild).
Include this plugin into pom.xml portlets
Rebuild your portlet.
The JAR will be placed in your .m2 folder, then each time that you rebuild your Service Plugin will be updated.
If i understood your question correctly, You need to create service builder project using maven and then you can add as dependency in other project wherever you need access to use xxxLocalServicutil class.
You can follow below link to create maven service builder project.
http://www.liferay-guru.com/how-to-use-liferay-servicebuilder-archetype/
As you mentioned in your question.
was also finding the xxx-portlet-service.jar but didn't able to, so
that i could manually put it in other portlet's lib folder
To answer this, manually putting .jar file in lib directory will not help when you are working with maven project

Configure manifest.mf classpath in ear

I have an ear application which has 3 modules:
web.war
services.jar(ejb)
domain.jar(ejb)
I worked with maven tutorial:tutorial
At the end author says about problems with manifest.mf in web module and suggesting some solutions. But this not worked for me. I think configuration is broken not only in that case. In my ear MANIFEST (classpath) i have also prefix "lib/" before services module(services are separated jar as ejb module in my app).
I saw i can use my specific prepared Manifest.mf, but i don't know how to configure it manually. Could I duplicate jars in my app modules? For example add domain.jar in services and web? Is it correct?
I have specific structure:
1.sample-ear with web and services module
2.sample-web with sample servlet(without dependencies from other project in code).
3.sample-services with dao classes(using entities)
4.sample-domain with entity beans
I tried modify manifests in every package, but I didn't find a solution. When i want to run my application on WildFly10 i get NoDefClassError (Class from domain.jar used in service.jar). Could anyone help to configure it?
On the other hand maybe you have better maven configuration in project and manually configuring the manifest.mf is not needed.

What is the use of converting jars to bundles in WAB(OSGI)?

After exploring the OSGi framework, I had developed a sample web application.The Web Application Bundle(.war or .jar) is packaged inside an eba.
The war file contains a bunch of embedded jar files in its WEB-INF/lib
directory.These jars have been converted to OSGi bundles(using maven-bundle-plugin) with the required export and import packages as per the relation between the jars.
Now I have to even mention all these jars(WEB-INF/lib) in the bundle-classpath.
The above works because a bundle(wab is also a bundle) can include one or more jarfiles within it, and use a Bundle-Classpath manifest.mf entry to point to them.
Incase I dont include the jars in the bundle-classpath I get a ClassNotFoundException.
The question is,then there's no point converting the jars to osgi bundles.Obviously all the jars in the WEB-INF/lib are loaded by the same class loader(i.e wab's class loader) ,so then we are not reaping the major benefits of OSGi which is mainly a per bundle classloader concept?
Putting jars inside the WEB-INF/lib is the old-style normal-java way of handling dependencies, and putting them outside the war is the new-style OSGi way of handling them.
By packaging your war's dependencies in WEB-INF/lib, you're treating them as normal jars (remember a bundle is also a jar). So in that case, you're right that there wasn't much point in using bundles.
One of the benefits of using wabs instead of wars is to get away from the dreaded 100 Mb monolithic war. Rather than packaging the bundles inside WEB-INF/lib, try having the war import the packages it needs using Import-Package:, and package the dependencies inside the eba. (If you don't remember to have the war import the packages it needs, you'll get the class not found exceptions you were seeing, because the OSGi container won't know your war needs those packages.)

Externalizing static content from a WAR and serve both on jetty

In my project I use Maven to package a web application to a WAR which is later deployed to Jetty using a custom Maven plugin on CentOS. The custom plugin is used by every project that deployes to a production environment. There is now a requirement that all static content (like web site text, properties) is packed outside of the WAR so that it can be changed in production without requiring a new release cycle. I am unsure how to achieve this externalization.
The Jetty server has the directory structure described in Jetty quick start guide. Currently, the web application already offers some .properties files which can be altered externally, and these reside in the resources/ directory. These files are moved here by the custom Maven plugin. The WAR resides in the webapp/ folder. One option for my problem is to use <packagingExcludes> of maven-war-plugin to not include e.g. *.xhtml and *.properties in the WAR. Later, I can use the custom Maven plugin to move excluded files to resources/ directory. But, I have a feeling this is not the correct way to externalize static content... Shouldn't xhtml files live in webapp/ folder while the only the properties file live in resources/ folder?
I have also researched the option of deploying the WAR as exploded, but I am unsure of the implications of such. Clearly, the changes in the exploded WAR files will be overwritten in the next deploy, but the idea is to do static changes both in development and production. Also, I am not sure how to achieve WAR "explosion", is it something that Jetty does for your WAR if configured in jetty.xml or do I have to extract the WAR before deploying?
Lastly, how do people serve static content in Jetty which can be altered in production? Do both the WAR and static files live side by side
The Jetty resources folder should not be used for application files. A J2EE web application (war) should be self-contained -- and in Jetty, reside only on the /webapps folder -- and its only binding to the container (Jetty servlet engine) is via the web.xml deployment descriptor.
Since property files may be read from the classpath and the Jetty resources folder is part of the system classpath, a property file there could be read by the web application class loader. Note that there are other ways to read property files as well and the Jetty resources folder should not be used for application properties. Also, the application may not be portable as other application servers have different forms of webapp classloader isolation.
If the below architecture approach does not work for you, then your only approach would be to expand (explode the war) in the /webapps folder and hope for the best when files are edited.
Tackling this from a different angle,
- if your web application depends on .properties and .xhtml files in order to function properly, then these files are probably not 'content'. The fact that there is a business process that requires them to to be updated ad hoc does not make them content.
- 'content' is something like text, images, and videos that is added, edited and removed by an administrative user. The application does not depend on it for correct execution, it merely reads and passes it on the browser.
Suggestions:
I would suggest that you deploy your application every time there is a change to the .xhtml or .properties files change. If the editors of these files are power business users, you might think of a git push-pull tool for them and a continuous build hook, so that when they make changes and push them to the git repository, the application gets tagged with a newer version and gets built and deployed. If there is a problem (tag not closed in xhtml), then it would be easy to roll back to the last tag.
Alternately, if the changes are minor (such as text descriptions), then modify the application to read them from an arbitrary external file (outside the webapp) -- a location that is provided to the webapp on startup. You can then package a 'default' version of the file in the webapp, but the code would attempt to look in the specified external location first.
I discovered that you can add HTML tags to properties and later use <h:outputFormat> to fetch these properties with parameters. Also, you can do pretty neat stuff with property files as described in MessageFormat API.
My solution was to keep the .xhtml files inside the WAR, but use simple HTML snippets properties from the default resource bundle which is based on a .properties file. These properties were included in the .xhtml using <h:outputFormat>and <h:outputText>. This allows the user to add simple styling like bold and underline to the snippets.
The properties file are copied to the Jetty resource folder using the custom Maven plugin, so I have kept the .properties files in the WAR. For some reason the Jetty resource folder has precedence over the packed .properties files, so this works out fine. Also, as Akber pointed out, I will have the default versions of the properties available if for some reason the WAR was moved to some other application server where the resource folder is not available.
Of course, with this approach the code can break if malformed HTML is placed inside the snippet properties, as pointed out by Akber, but it works for our application as it is very small. I may never have done this if this was a much larger application, but then I might have gone for a database based solution for adding static text (like Joomla/Drupal/Wordpress).

Websphere 6.1 server

I have an issue in loading jars in websphere server. Some of the jars are present in WEB-INF/lib and some are present in local hard drive(ex., c:\lib folder). How can i load all these jars, during the startup of the application. If WEB-INF jars are loaded, external jars are not getting loading and viceversa..Need help on this....
WebSphere has a hierarchy of classloaders, parent classloaders cannot see child classloaders, hence you get surprises when you put different aspects of your application in different places.
Never attempt to place application jars in WebSphere's own lib directory, and never adjust WebSphere's own class path. There is ana rchitected way to make external jars visible, I'll explain that in a moment.
There are three places that you can put JAR files so that they will be loaded. By far the the best is simply to place the JARs in WEB-INF/lib. You can specify the search order preference PARENT LAST so that these take prececdence over jars supplied by websphere - but note that some fundamental jars cannot be over-ridden You cannot replace the IBM security for example.
Second you can add jars to the root of the EAR file. Noe that the hierarchy comes into play now, WEB-INF/lib jars can see EAR jars but EAR jars cannot see WEB-INF/lib jars.
Finally you can specify a WebSphere "Shared Libarary". See the Info Centre for how, it's very easy through the console. A shared library has a classpath, you add jars to that. Then you allocate the shared libarary to individual applicaitons or whole servers.
Once again You WEB app can see the shared library, but i don't beleive taht the convers is true. Hence putting framework code in a shread library may not work for you.

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