EJB3 initialization code - ejb-3.0

I've searched this for a while now, but can't seem to find an answer to this. How can I execute some code in when deploying an EJB3 jar-file to a JBoss server? For example, I need to run some sql migration scripts before the beans are ready to be used.

If you can't use EJB 3.1 (with #Singleton #Startup), I would recommend packaging your EJB module in an EAR with a WAR. Add a ServletContextListener to the WAR, and take your action in the contextInitialized method.

You can create a JBoss MBean service with a Listener that can perform any initialization (SQL scripts run in your case) after JBoss is fully started and before any EJB is used.
I have created such a service and we run it on JBoss 4.2.3.GA, so, you do not need to migrate to JBoss 7.

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Extend Kie-server in CDI environment

I want to extend Kie-server in a CDI environment (Wildfly 19).
I'm following official doc: https://docs.jboss.org/jbpm/release/7.45.0.Final/jbpm-docs/html_single/#_cdi
Currently, I have a jar file containing CDI environment producer class and some CDI beans for initialization. I put this jar inside kie-server\WEB-INF\lib manually.
Is there a way to build a war artifact using maven which extends kie-server? For example an archetype to use where I can package my jar without manual patch of the kie-server war?
Best regards,
Just in case someone has the same need.
I tried at the beginning jbpm-services-cdi with kie-server war but some services like deploymentService are present twice (CDI bean and kie-server deployment service singleton) which causes problems.
I ended up using kie-server services from ServiceRegistry.
Please note that ExecutorService is registered in ServiceRegistry only after containers are deployed. There is a system property to trigger containers synchronous deployment: org.kie.server. sync.deploy.
Thanks,

Is there any way we could figure out in code the environment where EAR is deployed?

I am facing an issue in my restlet project where I have to code some operations only if the EAR is deployed in Websphere in a restlet server project. Is there any way we can get information through code to find out where is EAR/WAR deployed? (Is the EAR is deployed in Websphere or Tomcat or other servers).
Try to instantiate some WebSphere API class. If you get a NoClassDefFound, it's probably not running on WebSphere. You might have to do class.forName(Websphere class), so your code will compile outside websphere.
If you only need to check that for example in Servlet/Filter class you can look for servlet context attributes related to WebSphere, for example com.ibm.websphere.servlet.application.name = Default Web Application. You can find some attributes looi=king at the /snoop servlet if you have that installed.
Or, as Bruce suggested try to load some WebSphere class and be prepared for errors when they are not there.

SpringBoot war and JNDI DataSource standalone not working

I have a SpringBoot2-Application configured as a war package that I want to run on the command-line but also be deployable in an application server.
Per the instructions, I configured the dependency to the embedded Tomcat to scope "provided" and also added a TomcatServletWebServerFactory to override the initialization of the embedded Tomcat so that I can enable jndi.naming because I want the datasource to be read from the jndi of the application server. In case I start the application standalone, I provide the jndi-resource by adding it to the embedded Tomcat during start.
This fails nicely: if the scope is "provided" and starting standalone, my TomcatServletWebServerFactory is not run and jndi is not activated so the lookup of the datasource fails. But that package works fine in Wildfly. If I remove "provided", the standalone application starts fine but it crashes in Wildfly out of obvious reasons (there is a Tomcat instance started to many that can not be cast to an Undertow-instance).
Has anybody else experienced this and has a solution? What does the SpringBoot-Maven plugin do to "hide" an embedded Tomcat in a war? Maybe my TomcatServletWebServerFactory has to adjust to the "provided"(hidden) configuration?
Thanks for all suggestions.

Does spring boot needs a WAS (Websphere Application Server)?

In my theory spring boot is capable of running java web application stand-alone. It says it has a own embedded servlet container and can use JNDI itself.
I built a war file before (spring-mvc, security, gradle built), but Spring boot assemble jar file and it runs on any machine which has JVM.
So my question is, if I made a spring boot based web app (contained JSP files & JNDI for looking up datasource), although it has own embedded servlet container and packaged jar file for running standalone, do I still need to package it as WAR file and deploy it in WAS (Websphere Application Server) or servlet containers for any reasons such as performance, stability, scaling-out etc?
WAS is an full blown Java Enterprise Application Server, on the other hand you have Spring that only requires a Servlet Container (Servlets are a part of full JEE).
Servlet Containers are for example: Tomcat, Jetty, but also WAS.
Spring Boot is able to package the complete application TOGETHER with the code of Tomcat in an JAR, so that this jar contains the Servlet Container and your Application.
Do I need a additional WAS for performance, stability, scaling-out etc?
Performance: No - There should be no important performance differerence between Tomcat and WAS when you run a Spring-Application. (Only that Tomcat needs less memory for itsself)
Stability: Tomcat and WAS are both very mature products.
Scaling: You can build a cluster of Tomcats by your own.
The main features of WAS over Tomcat are:
- WAS supports EJB and CDI (Tomcat would need TomEE for this), but Spring will not use it, because it is its one Dependency Injection container
- WAS has more Monitoring features, but this does not matter, because Spring Boot has Actuator
#See Difference between an application server and a servlet container? for more details
Simple answer is No. You do not need any Full blown application servers for any of the reasons that you mentioned (for performance, stability, scaling-out). You can just do fine with tomcat
Edit
Looks like you are using only JNDI feature from the Application server. Do you really need JNDI when you pack your servlet container along with your application ? I don't think so. That days are long gone.
JNDI really shines when you have to move an application between
environments: development to integration to test to production. If you
configure each app server to use the same JNDI name, you can have
different databases in each environment and not have to change your
code. You just pick up the WAR file and drop it in the new
environment.https://stackoverflow.com/a/7760768/6785908
(If you still need JNDI to be used to look up your data source refer: https://stackoverflow.com/a/24944671/6785908).
No, still I do not really see a reason for packaging your application as WAR and deploy it to traditional application server. That being said, if you have some existing infrastructure lying around and you are being forced to deploy to existing WAS (or WebLogic or JBoss any application server for that matter) server, then I rest my case :).

Best alternative to Weblogic startup classes in Websphere?

I am working on a Server Migration Project from Weblogic to Websphere. The problem is that in Weblogic, we are already using a class specified as Startup-class in Weblogic (and arguments to the class like log4j config file) which is present in a jar which is added to Weblogic classpath by editing the startup script. This jar initializes a global log4j file which is for all the apps deployed on the server and not for any particular app. Each app is distinguished by a category of log4j.
Now I could not find a similar thing in Websphere. So what is the best solution? I can create a new application which would do all initializations like that of the startup classes. I thought of using startup-beans but read in some IBM documentation that they are deprecated due to EJB 3.1 Session Beans. Also how to make sure this app loads first? By giving Websphere xml file startup weight 1 like here?
I am using Weblogic 6.3.2 and Websphere 8.5
The WebSphere migration toolkit suggests to replace the WebLogic T3StartupDef and T3ShutdownDef implementations with either a ServletContextListener implementation, session startup bean (Singleton), or a servlet that is configured to load at startup time. If you haven't used the WebLogic to WebSphere migration toolkit, check it out. It provides a lot of help especially with deployment descriptor extensions.
The #Singleton session bean in EJB 3.1 replaces the proprietary WebSphere startup bean.
The best approach depends on the type of module you need the startup logic.
If you are considering the custom services option, note that the com.ibm.websphere.runtime package is not available in Liberty if you are considering the Liberty server.
It sounds like custom services (or a custom feature on Liberty profile) are the best analog if you need to run logic during server startup. Otherwise, if you just need to add a library to every application, then create a shared library and then either associate it with the server or associate it with specific applications or modules.

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