The docmentation only tells me how to add more connectors, but I cannot find anywhere to tell me how to stop those connectors from being loaded. Removing the camunda-connector libs from the classpath just causes the ProcessEngineConfiguration to throw ClassNotFoundException.
We use Camunda 7.17.0 as an embedded workflow engine that doesn't need to be accessed through REST or SOAP, so I want to close those avenues of attack.
Related
I have a very typical problem. I am using in-house developed platform which uses Jetty server and rest easy to provide a wrapper over REST framework. When they did that they made lot of tweaks for some specific scenes.
Now problem is that when I developed a REST based service with raw interfaces of rest easy and embed my jetty server in same JVM. My service can receive the request but response is always 500 server error.
I feel the in-house framework is intercepting the response doing some security validations so my response doesn't reach.
I was wondering if there is a way to use the different rest easy version and run in same JVM. I have tried to embed a jetty server and added a normal Servlet and I can access it but I can't achieve the same with my rest based servlet.
Any Idea how could I load two versions of rest easy on same JVM ?
What you can't have is two applications in the same web application context, since you are supposed to define only one class implementing javax.ws.rs.Application.
But that shouldn't be a problem, as long as classes live in different ClassLoaders. Each web application context must be in isolation of other contexts, each defining its own ClassLoader.
You can perform all kinds of class loading manipulation in Jetty: https://wiki.eclipse.org/Jetty/Reference/Jetty_Classloading
In conclusion, as long as you use different jar files of RESTEasy in each web context, you should be able to run two REST applications using different RESTEasy versions in the same JVM process.
I'm having trouble wrapping my head around how to use servlets properly
I've set up a postgres database, and downloaded a JDBC driver for it.
What I want to have is my webpages post to the servlet, and the servlet get info from the database. I understand how to code everything (eg add library for driver, open connections, execute queries), but I think I'm lacking knowledge in how to set up the file structure.
I have the postgresql database running on pgAdmin. Do I also need to have a server running to make the servlets work as well? Can't I just make a web.xml file that maps to the servlets, and open the webpages to use the website? If I run the project through an IDE with a server running (glassfish) everything works. If I close the IDE and go to open the webpages on my browser again, I get 404's whenever I submit to a servlet.
Can someone give me a bit of guidance on the big picture of how everything is supposed to interact (with details on servers please). I've been searching the web and I havent found anything that explains the big picture very well.
Thanks
A Java web application is a set of files obeying a well-defined structure, and which can be packaged in a war file.
This web application is deployed into a server (also called container), which understands the file structure, listens to HTTP requests, and calls the appropriate servlet of the appropriate deployed web application when it receives one.
And of course, if you shut down the server, nothing listens to the HTTP requests anymore, so you won't get any response.
You could read the Java EE tutorial for more explanations.
In fact, I'm trying to see which would be the best approach to achieve play framework native support on openshift.
Play has it's own http server developed with netty. Right now you can deploy a play application to openshift, but you have to deploy it as a war, in which case play uses Servlet Container wrapper.
Being able to deploy it as a netty application would allow us to use some advanced features, like asynchronuos request.
Openshift uses jboss, so this question would also involve which would be the recommended approach to deploy a netty application on a jboss server, using netty instead of the servlet container provided by jboss.
Here is request for providing play framework native support on openshift There's more info there, and if you like it you can also add your vote ;-)
Start with creating 'raw-0.1' application.
SSH into the server and
cd $OPENSHIFT_DATA_DIR
download and install play into a directory here. $OPENSHIFT_DATA_DIR is supposed to survive redeploys of your application.
Now you can disconnect from SSH.
Clone the application repository. In the repository, there is a file .openshift/actions_hooks/start. It's task is to start the application using a framework of your choice. The file will need to contain at least (from what I know about Play)
cd $OPENSHIFT_REPO_DIR
$OPENSHIFT_DATA_DIR/play-directroy/play run --http.port=$OPENSHIFT_INTERNAL_PORT --some-other-parameters
Important
You have to bind to $OPENSHIFT_INTERNAL_IP:$OPENSHIFT_INTERNAL_PORT. Trying to bind to different interface is not allowed, also most of the ports are blocked.
To create some sort of template, save the installation steps into .openshift/action_hooks/build file. Check if play is installed, if it is do nothing, if it's not, execute the installation process.
I am new to jboss and would like to know what are the differences between ServiceMBean and load-on-startup servlet tag in web.xml? Also, I would like to know which one will always get loaded first or they are loaded at the same time? In what situation, I should use MBean and when I should use startup servlet or it doesn't matter?
I need to write a a class/servlet to validate if all the required system properties (e.g -DINSTALL_DIR=blah ) is set. If not, then stop right there. else proceed and start the application.
Thanks in advance
-A
ServiceMBean is JMX, it is part of your JVM. load-on-startup servlet tag in web.xml is part of your J2EE application.
JMX is part of J2SE starting from JDK 1.5. So, you can have one ServiceMBean per JVM. not per application. JMX is used mostely for monitoring and managing the JVM. It provides access to information such as: number of classes loaded and threads running, memory consumption, garbage collection statistics, on-demand deadlock detection, and others. Another common use, is to refresh your cache.
JMX will allow you to instrument your application and control/monitor it using what-ever management console that your JMX container supports. An example would be a web application that implements a reference data cache...
A problem we had before was we would occasionally need to refresh the cache because a customer name changed in the database. If we had a refresh method on the MBean interface then we should be able to trigger this event using the JMX console. The JMX console may be a web or fat client that comes with our J2EE server. Our J2EE server may also support SNMP. This means that we may be able to invoke the method from a standard Tivoli or UniCenter console.
http://www.theserverside.com/news/1364664/J2EE-Application-Management-The-Power-of-JMX
You don't need remote access to ServiceMBean in order to trigger some asynchrious action. Moreover, you need validation on scope of application, not the whole JVM (while, you can, theoretically, handle this issue in the ServiceMBean). So, it is more naturally, to do it as load-on-startup servlet tag in web.xml. In this way, in every start up of your application validation will happen.
One more clarification: ServiceMBean is JBoss-way to write JMX. All MBeans are server wide (not application wide). That's why I use MBean and ServiceMBean freely above.
I have a scenario where during the system install time, a few services were deployed on to the OSGi container and these services will be listening for other bundles that provide data and are dynamically installed and uninstalled at runtime.
These data providers do not expose any services and should not even invoke services; my idea is to enable the pre-deployed services to listen for the event of installation of these data provider bundles and if the pattern matches, then process and persist the data into the data store.
For example I have a WidgetService which will listen for installation or uninstallation event of Widget data provider bundles, ShppingCartService that will listen for the installation/uninstallation events from ShoppableItem data provider bundles, etc.
This helps me to keep the processing and persisting logic be centralized and my data providers need not write any code to make their data processed. All that is expected from the data provider bundles is the Service Name/id, Service Version,PreRequisites, and the data that they need to publish.
I have read several articles on OSGi that explain dynamic pluggability of services and the clients able to discover or discard services based on their availabity; however, those are all talking about scenarios where clients are to be intelligent to discover and execute the services they are interested in.
My intention is to make client completely unaware of any service discovery, for that matter any code. All that the client passes is the info about the service the client is interseted in, the dependencies, and the data; the client should be completely dumb.
Is this possible in OSGi? I'm ready to consider this architecture even at the cost of extending a few of the OSGi core framework classes!
I have found some what, may be, remotely related question on stack overflow at :
Discovering Bundle MetaData with out installing the bundle
However, I want a hook or an event that will call my respective service when one or more data provider bundles have been installed. These data provider bundles can be interested in any of the services that are installed in the system. I'm even ready to write a central bunle repository manager/listener kind of stuff that will listen to any bundle installation and invoke my Service facade that will decide which service to execute based on the meta data provided by the data provider bundle.
I'm just starting OSGi, so need a little direction on how to move forward...
I'll be really thankful to you guys/girls :) if you can help me achieve this!
I have a doubt deep in my mind that this may not be readily available in OSGi, and even if that is true I'm ready to spend time and extend the framework to achieve this. All I need is a few guidelines and a clear direction. Who knows, if OSGi is really lacking this functionality, then it would be a very useful add-on to a future OSGi spec.
You might have a look at section 4.7 (Events) of the OSGi Core spec. The Framework raises BundleEvents when there is a change in the lifecycle of a bundle, e.g. when it is installed or uninstalled. What you need to do is to implement a BundleListener, which then will receive the events, so your service can react on the changes.
I have described a design pattern that I call "OSGi Mediator", which may be a solution to your problem.
The items you want to mediate would only require to register with the service registry; all the dependencies could be managed by your mediator implementation.