I am currently writing a web application which uses JBoss6.x as the application server, for load sharing what I have decided is to write some EJB's which can be either run locally on the same machine as the web application on the Jboss or in a separate machine which will be remotely connected which will have Jboss running on it.
Now the question here is, I would be needing only 1 JBoss server to serve the web application, all other Jboss in question should be running with only the EJB Containers. Is it possible to run only the EJB Container and the naming services so that I can remotely connect to the same? Pointers or specific links as to how to go about doing this would be much appreciated.
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I have a stand alone Java application that needs to get information (string data) from a Java EE application, running on a Glassfish 3.1 Application server. I have created a web service for my Java app, but I'm wondering how I could achieve communication with the Java EE glass fish app (using servlet?).
I hope to have a method on my app that can be called from, for example, a client running on glassfish (and vice-versa). This method would have something like a String array as parameter, so that I would be able to pass the data between the apps.
Note: I am unable to deploy my app on Glassfish, since we are trying to achieve separation till we are sure the application I am developing will not cause Glassfish to crash ( we currently have other critical apps running on Glassfish). Also note that this is all taking place on the same machine.
You should develop a web service and deploy it on Glassfish within your existing application. You can do this via a Servlet based web service, or a Session Bean web service, whichever is more appropriate for you.
You will then create a web service client against that web service for your Java app, and integrate it appropriately with calls to the servers via the web service.
Of course, this should all be done against development servers, not your production servers. Glassfish can be deployed pretty much anywhere: your machine, another machine, a VM, in "the cloud". Not having a development server available for, well, development is unacceptable. There is no way you can determine if your app will "crash Glassfish" unless you can test it.
To quote the esteemed Donald Knuth: "I have only proved it correct, not tried it."
Get a test server, develop against it. Move forward.
Have you looked at the URL class.
try this url Java URL example
This may help
I am new to Java EE. Does EJB need a dedicated server in order to be used or can I potentially make a Java EE application simulation on my laptop via only a web server?
EJB need an application server like JBoss, WebSphere, WebLogic, GlassFish, etc.
Pure web servers like Tomcat or Jetty cannot run EJB.
All application servers can also function as a web server.
So the answer to your question is - no, you can't run EJB only via a web server but yes, you can run an application server on your laptop and use it to run web and EJBs.
A more technical explanation is that you need an EJB container to run EJBs and a web container to run servlets and JSPs. A web server has only a web container. An application server has both.
You need an EJB container to run EJB with all the features (i.e. transaction, security etc.). But if you are are using EJB3 you can use something like ejb3unit to unit test the functionality of the EJB classes.
http://ejb3unit.sourceforge.net/
You need a EJB container to run EJB applications. However, it is easy to run one on your computer, just as it is easy to run Apache server for HTML/PHP applications. Glassfish is an example server which contains an EJB container.
If you only want the EntityManager functionality from EJBs, then you can simply use Java SE. See here.
I ‘m trying to create a small EJB 3.1 application in which I want to use two application servers from two different vendors. (JBoss 6.1.0 Final and Glassfish 3.1). This is just to experience the taste of distributed applications and new features of EJB3.1.
This is the problem I’m having…
I have created a simple EJB (kind of a hello world ejb) and deployed it in GlassFish server which is running in the machine A. Let’s call it GlassFishHelloWorldEjb. This one has business remote and local views.
I have created another EJB project in which I have an EJB called JBossHelloWorldEjb. I have deployed it in the Jboss server which is running in the machine B.
Now I want to inject GlassFishHelloWorldEjb to a reference in the JBossHelloWorldEjb so that I can call it within the JBossHelloWorldEjb. Then I have a web app deployed in the Jboss which calls the JBossHelloWorldEjb.
MyWebApp(Jboss, machine B)-----> JBossHelloWorldEjb (Jboss, machine B)----> GlassFishHelloWorldEjb(GlassFish, Machine A)
I tried many ways to inject the GlassFishHelloWorldEjb in to the JBossHelloWorldEjb but failed. Could some please shed some light to achieve this.
Would greatly appreciate if you could show me the way to do this through both INJECTION and Programmatic JNDI look up.
Cheers
Lekamge
one option might be to use Spring RemoteEJB Proxies
OR. import client required jars for remote and write your own wrapper
Apache Derby has an option to run its "Network Server" as a web application in a servlet container (derby.war).
The problem is then how to deploy other applications that depend on derby in the same container to load after derby loads (preferable in a Tomcat container).
From what I recall there is no way to control the order of web application initialization in Tomcat.
Has anybody gotten derby.war to work in a multiple web application environment?
You'll probably find it easier and more reliable to run the Network Server in a separate standalone process of its own, rather than as part of the Tomcat process. It will make it easier to start, stop, control, and administer your Derby databases separately from your applications.
I had a similar issue too, but with HSQLDB. I went to using standalone instances.
Does Tomcat use a different Java Virtual Machine (JVM) for each web application running in its container, or does all web applications in Tomcat run under the same JVM?
So for a specific example: if a web application under webapps, enables JMX programmatically (via System properties) does this mean that JMX is enabled for all web applications running in the container?
I believe this is the case, but would like to confirm.
This question came up from my problem in this thread: question on tomcat and jmx. Any input on the subject is appreciated.
Tomcat runs in a single JVM, so every app deployed to a single tomcat instance runs in the same VM as every other application. They get different classloaders, so they're isolated from each other in that sense, but the JVM is the same.
So any feature enabled JVM-wide will be enabled for every application in that instance.