I am looking for a simple hornetQ example that does not use JMS, JNDI or the JBoss AS. Most of the examples included in the release use JNDI and JMS, or the JBoss AS. I've looked at the embedded examples, but I don't want to run hornetQ embedded in my application. Could someone please point me in the right directions. Thx.
It was impossible to us to write every single example in core and JMS API, and maintain both working.
For that reason we have included just a few core examples, and the JMS examples.
JMS is just a thin layer on the core-api, and all you probably need to know about the core-api is there on these embedded and core examples.
If you have any specific question about the API, or you're looking for a specific example I can help you with.
You could check the examples of chapter 3 of the new HornetQ book
www.amazon.com/dp/1849518408/?tag=packtpubli-20
Related
I have a CQRS/Eventsourcing architecture with 3 microservices. I implemented 2 microservices with vert.x 4 and I implemented CQRS/Eventsourcing without framework to improve my knowledge of this type of architecture. For the third microservice I would like to use AxonIq Framework but I have a problem with Aggregate annotation because it's not avalaible with vert.x but only with Spring.
I implemented a Spring microservice using Axon and everything work fine but I would like to know if someone can help me for use vert.x with AxonIq ? If anyone know a workaround for this problem ?
Thank
Axon Farmework provide something called Configuration API. You can have a look at the Configuration class but for making use of it, you need a Configurer, which will provide you all means of configuring your components!
On the ref-guide, you also have several examples of how to do the configuration using the API or Srring Boot. Example for Commands can be found here.
To help a bit more, I can also share a small project I made using Dropwizard and Axon Framework, meaning no Spring was used and all the Configuration was done through the API.
You can find it here https://github.com/lfgcampos/axon-playground/tree/master/chat-getting-started-dropwizard
A question is running into my mind for a several days ago.
I read several docs about vert.x and quarkus.
Which kind of message are sent throuh event-bus? Only received http request?
Has it sense to configure an clustered eventbus inside a quarkus application? Any example?
Those above question have not been able to find some lights.
Any ideas?
You can send any type of message through the Vert.x Event Bus, as long as a codec exists for this particular type. There are several built-in codecs, but you can register custom codecs too.
Quarkus does not support clustering officially so far. You can make it work with some tweaks, though.
From my perspective (I'm a Vert.x development team member), it can be useful to have a clustered eventbus inside Quarkus, just as it can be useful inside a Vert.x application. There are plenty of articles on the web about use cases.
I've created a RESTful web service using jersey and JAX-RS annotations. It's also documented using enunciate and looks great. However, SOAP support has been requested as an option. I noticed in this outdated enunciate example JAX-WS and JAX-RS annotations in the same class. Is this possible? I've tried it myself and enunciate generates documentation correctly, but the services don't actually work.
I'd prefer to have the exact same class support both interfaces rather than two separate classes (one soap one rest) pointing to the business logic class. This would prevent possibly having code in two places.
Here's the example on outdated software versions:
http://docs.codehaus.org/display/ENUNCIATE/A+Rich+Web+service+API+for+Spring
I'm using
Jersey 1.8
Spring 3.0.5
Weblogic 11g
Thanks!
/Chip
I'm not sure what might not be working, but a lot of the Enunciate example modules use both the SOAP and REST annotations on the same class.
Here's one for Jersey/JAX-WS.
Here's one for JBoss WS/RestEasy.
Here's one for CXF.
We ended up making a separate service for SOAP than the REST service. We also found it best to have interfaces for each that enunciate could generate from. This way we could control what documentation it generated. It also started functioning smoother. Still having a problem with the namespaces though as they're all default and ns0 is generated but enunciate links are to ns2/3/4/5/etc. So many links are broken.
I want to exchange data between two applications JEE6/JSF2.0 and i'm looking for the best solution. I thought of the below solutions :
by using a JSON file.
by using XML file.
by using GSON file.
by using Remote interface (EJB 3.0).
For you, what's the best solution to use ?
edit : This two applications will be always running on the same network (but can not be on the same JVM)
I want to provide an alternative to David's answer, as I feel that there are some drawbacks to RMI that he underplayed.
This is a Java specific technology. If a third server needs to be introduced and it is a Microsoft Reporting Services server for example, then it cannot talk in the same language.
RMI is an OLD technology and doesn't particularly look well on a CV. Web services are the future. Experienced RMI developers are more uncommon than experienced web service developers.
Cumbersome and heavy framework
A better solution in my opinion would be to use SOAP XML based web services. Here are some advantages to this approach:
Universal acceptance in nearly any development framework. No matter the technology, nearly all have helpful libraries for interacting with web services.
Java has good support for object serialization into XML. This means objects can be quickly serialized into a SOAP XML request, sent to the other server, and deserialized back into a Java object by the other application server for processing.
A service layer can give you the decoupling interface between the two applications just as RMI can.
I hope you reconsider the use of SOAP XML based web services in your application.
There's two options really as you yourself stated.
Using RMI to connect to a EJB or using a webservice and communicating by JSON/XML etc...
From my experience RMI can be favorable if your applicaitons are on the same network, if not then you might get problems with firewalls etc and be forced to tunnel the RMI using HTTPS... which pretty much makes the RMI calls webservice calls.
If your on two different machines then webservices are nice as they dont cause as much trouble with firewalls. Also as they use the HTTP protocol you dont have to worry about the data being transfered.
These examples are kinda generalised but should give you some insight.
GSON vs XML vs JSON is a completely different subject... Non is superiour to the other, and all are fairly easily read by the human eye.
UPDATE
From what I've understod you wont have to worry about firewalls and such, I would recommend using RMI. It usually results in cleaner code and somewhat better performance.
Since I have seen both in action, I can make a comparison between the two technologies, EJB and WebServices. I can confirm that EJB is way more efficient, has support of transactions (including distributed transactions, if that is your requirement), exception handling, and binary streaming out of the box. In terms of performance EJB may exceed SOAP by a factor of 5 times in speed, and REST for about 3 times.
However, EJB is not an integration technology. In fact, it has never thought to do so. The biggest flaw of EJB is that it is very coupled to the Java Platform. Therefore, both endpoints must be written in Java and should use the same Java EE version.
Another problem is that EJB is not a protocol per se, so the implementations from two containers/vendors is probably different. If you need to access a remote EJB from JBoss AS on an Oracle WebLogic server, you must bring JBoss EJB client implementation with you.
Another big problem related to integration with EJB is a lack of data exchange format. Since it uses Java Serialized objects for communication, the data types must be shared on both ends. If you create a new exception type on the server that is classified as an Application Exception, if the client who consumes this service triggers the exception, his code will break. Note that, in this case the remote API was not violated, but another unknown type was introduced.
And, of course, by depending solely on the class type as an exchange format, you are giving the programmers opportunity for doing very stupid things. If you have many different teams in large projects using EJB as integration technology using different versions of Java EE, prepare yourself to experience uttermost pain. I've seem a programmer including a JPA entity on the client, who was annotated with named queries, the table which was accessing, its columns, etc, essentially giving away all the database layout to the service consumer. But it can get even worse. I've already seem a programmer returning a data structure that belonged to a dependency, namely Eclipselink 1.0. However, if you access this from a JBoss server, Eclipselink is also a JPA implementation technology, which conflicts with JBoss' hibernate. So, now you have to include Eclipselink jar in your JBoss APP classpath and configure the container for not loading JPA related packages, which otherwise will break your application completely. Even so, it can get WORSE than before: some other service you need to connect had also the bright idea of using the same datastructure, but now from Eclipselink 1.1.1, that has a different implementation, but the same class signature. Now you are in a very bad situation.
The bottom line: NEVER, EVER, use EJB as an integration technology. Use SOAP using a contract-first approach, where you define a canonical data model for the application, mapping java datastructures to a XML exchange format that can be used by any client, be it written in any language or using different stacks. Or use REST implementing a resource based, using HATEOAS principles. These days I rarely seem a reason for using EJB at all, since CDI is now on the market, support many features that EJB does and does not include any RPC related technology.
I'm learning how to develop with OSGi in recent days, but facing a lot of problems.
I don't know how to design my client-server system based OSGi with Equinox as framework. Should I use socket connections to implement this or use a distributed model?
I'm also confused whether I need to import some third party packages to support my programming on socket, jdbc, swing, etc, or there're existing packages offered by Equinox or other OSGi open source projects?
First time to ask questions here, can anybody help me?
just take a look at OSGi Remote services implementations (more details in OSGi spec):
Web services (Apache CXF: distributed OSGi) - http://cxf.apache.org/distributed-osgi.html
Eclipse Communication Framework - http://www.eclipse.org/ecf/
Cheers,
Dmytro
The HTTP model is probably the simplest to implement, as opposed to protocols based on low-level socket handling and binary protocols.
The first question I'd ask is what kind of information your clients and server need to exchange. If you can live with HTTP (and in many cases you can), you can just use servlets on the server-side, http client libraries on the client side and a RESTful communications model.
Servlets are easy to implement in OSGi using the HttpService, see for example http://www.osgilook.com/2009/09/08/osgi-http-service-registering-servlets-on-the-fly/
Working with sockets is not more or less complicated in OSGi than it is in 'plain' Java. You design your application in much the same way as you would normally, but gain the benefits of modularity and services by using OSGi.
You could, for instance, decouple connection acceptance and request handling by introducing something like a WorkerFactory, or maybe reuse services on both the client and the server; those are the things that OSGi is good at.
OSGi as a 'technology' (as far as that notion holds water) does not mandate any specific interaction method. The compendium specification mentions Remote Services (a.k.a. Distributed OSGi), but it also contains an HTTP service specification is Servlets are your thing.
In short, just pick the interaction solution that best matches your scenario, and let OSGi help you with the services and modularity.