Assume we have a .NET application that exposes its web services. This app needs to be integrated with our J2EE application running on Weblogic. Both are internal applications so we don't worry too much about security.
There are no really complex data structures/types so we should be able to map them between .NET and Java tier (or at least write adapters on the Java tier to ensure the match).
What is the best approach of consuming these .NET web services in the J2EE application?
The simple approach would be to just generate WSDLs for the .NET web services, and generate Java client classes using wsdl2java or other similar tool and see if that can work without adapters/changes, create unit tests, etc. But in case of data related challenges we may need to deal with XSD/Schemas, generating classes, etc.
I know there is WSIT to deal with interoperability issues, but want to keep this as simple as possible. Any thoughts, ideas?
You could connect the two applications with a RESTful API. This lets them talk in a shared, high level API over HTTP. Both languages have plenty of support for both creating and using HTTP/RESTful services, so this should be fairly simple to implement in either language.
Related
I want to develop a web service.Out of Java web service and .Net Web API which should I select.
.My requirement is that it should be stable and should be effective in performance.Which should bare load of thousands of requests and won't fail.Out of this two which should I choose and why?
My suggestion would be implement Rest WS in Java, Since it's platform independent, rich API's, you can go with Spring for rapid development.
My suggestion is Java. I'm used to Java to build REST server that serve thousands request and it's still working well.
The Jersey is good framework for you. Also Java is open source and independent platform.
I am having a Java application and a .NET application both residing in two different machines and need to design a communication layer between these two applications. Any inputs or ideas would be really helpful. Below mentioned is the nature of interaction between these two applications.
Java applications sends large amounts of data to the .NET application
Data latency should be kept to a minimum
.NET application should also be able to request for some data (synchronously/asynchronously)
The easyest way .Net and Java can talk is using Web-Services - we have done in my company with much success (using apache's cxf and standard code on the .Net side).
But if latency and size are the main requirements, you should use Sockets - both platforms offer a pretty extensive socketing frameworks and it would give you the best performance possible.
I think this can be done by setting up an xml webservices layer on the java side. You can use RestEasy for restful web services. Just my .2 cents.
Another alternative is some form of MOM (Message Oriented Middleware). There are a lot of implementations, but one to look at first might be ActiveMQ as it has both Java and C# bindings (among others).
I'm not saying this is better than using a web-service, it entirely depends on what your requirements are.
We have had good experiences with providing web services with JAX-WS (part of standard runtime in Java 6). They explicitly list .NET compatibility as a goal and is well supported in IDE's.
The Endpoint.publish() mechanism allow for small, simple deployments.
You can use Web Services. Jax-WS is the API in java that allow you to use it. As the implementation of this API I recommend metro (http://metro.java.net/), this already came with the SDK, and has a great integration with netbeans.
As already someone referred yet, you can use a socket, and create a communication channel on that, but this have some problems, starting with security. Don´t use this in real life applications.
If you need help with this subject you can start reading this:
Getting started with JAX-WS
It really depends on your requirements. The simple way is generally Web services. However, if you want higher performance, or more fine-grained access to the API on the other platform, you might want to consider JNBridgePro (www.jnbridge.com).
Disclosure: I work for JNBridge.
I'm developing a web application with multiple frameworks (spring, hibernate, spring-security, ZK for GUI), and using Tomcat as app server. I must say I have absolutely no experience with java web services technologies. Thing is, I will almost certainly have to expose number of services for some external applications in the near future, and I was wondering what would be the way to go (considering the frameworks I'm using)...
I saw and read various tutorials and some questions (link) regarding Axis, Axis2, JAX-WS... Thing that confuses me a little bit is that I don't know what is the common practice (if any) to integrate services within existing web application (mainly in the terms of project organization). As I see it now, these services that I need to implement will rely partially on the existing source code, so I don't know whether I should use completely separate project, or I can put it inside my existing web app folder (which I tried with Axis2, but don't know if it's a good practice).
Thanks.
How to organize the projects?
In general I agree with #ericacm, but there is one thing you should keep in mind... You said you're going to develop a number of services in the near future. You may come to a point at which you want to host the services on a separate server, e.g. for performance, availability or maintainability reasons. This may influence your decision of separating the projects. Furthermore, separation "enforces" loose coupling, but therefore introduces other challenges like session sharing across multiple WARs. It's a case-by-case decision.
If I were in your situation I'd first ask myself whether the service(s) logically belongs to the web application or not.
Implementation
When in comes to WS-* implementations you have to make 2 decisions:
Decide for an API to use; today, I can't see any reason for not going with JAX-WS together with JAXB as API, they work well and they are standardized.
Decide for a Framework; I've experience using Axis2 as well as METRO (keep in mind that JSE 1.6+ provides basic JAX-WS support). Both work well. It's fairly easy to change the frameworks if you use the JAX-WS APIs.
I have good experience with Spring-WS 2+ and manual Castor mapping . Is is easy but powerful combination.
Spring-ws 2:
provides contract-first development (specially good for the web app with number of services).
provides WS annotation
supports XML mapping (Castor, JaxB, etc)
Castor:
mapping based on xml configuration
allows map multiple messages (requests/responses) to one java object (based on xml configuration)
If you are using some Java EE 6 server, consider also JAXB for manual mapping:
mapping based on annotation
should be faster than Castor
allows map multiple messages (requests/response) to one java object (when you use java inheritance)
You can go ahead and put them into the same project. Each web service will be an additional interface and implementation class along with some configuration.
Since you are using Spring CXF is a good choice as a for JAX-WS as it integrates well with Spring. See this page as a starter.
Spring-WS is complex framework for simple web services. If you want to understand web services completely and to know the nuts and bolts of web services, learn Spring-WS. It is extremely flexible and provides lot of options.
Else, if you want simpler alternative use JAX-WS. Spring supports JAX-WS annotations. Refer to the section 17.5.7. Exporting web services using the JAX-WS RI's Spring support.
http://static.springsource.org/spring/docs/2.5.x/reference/remoting.html
Is it possible to create WS Server and WS Client manually (without generators) by JAX-WS? Specially if you are developing a big application you want to re-use objects but generators are generating a lot of classes that can be in 99% the same (for example if your app is WS Client and you have to connect to badly designed external WS Server). Is there some tutorial how co create ws manually?
There is a lot of reasons why I don't like generators and completely agree with http://ogrigas.eu/spring/2010/04/spring-ws-and-jaxb-without-a-code-generator
I'm developing a java application or service for execute remote commands or another applications and receive the results of these commands. And I think about to project this application to be possible his use with a swing interface or a web interface.
I have to take care with the parameters to pass for my businnes classes and how I will deal with the results. I need to use a architecture and project that let me able to use my classes with a desktop application or web application too.
I believe this is related with API and service design. Some popular applications have a web interface or dashboard for control services, and the services are manageable by agents installed for execute some demons, services or applications. To do start or stop commands for database systems, directory services an other tasks
There are some guides to how develop applications and services in java that can I use with web and desktop environments?
I felling a bite confusing about this, because in my mind if I choose to develop this with a swing approach all the thinks turn clear for me. But when I imagining the same project using the web perspective I lose my directives.
Sorry and Ihope that someone could undertand me. :-P
Consider spring and MVC architecture. Neither of them is constrained to Web development only, however they are extensively used as such.
You might look into Naked Objects ,where you develop a domain object model and gets the UI more or less for free (You can get a desktop GUI, and various forms of web UIs). This is probably not a feasible approach if you're developing a public facing application, but more suited towards applications developed for expert users.
I have been in a similar situation recently while I started working on a simple CMS. I wanted my cms engine to be free of what UI/client is used to interact with it and finally I settled for a Web Service oriented approach. As a student of RESTful WS/ROA I usually like to take that approach.
If I understand your problem correctly, I would design it to be, each external program, service, web service I want to provide remote access to would be a 'Application' to my web service, where 'Application' would be a 'Resource'. Performing actions on the 'Application' resource would mean executing GET requests with different query parameters. How the 'Application' infers would depend on the 'Application' resource.
A similar approach I took in the CMS engine is for generating representations for a content. I support Ruby (JRuby), Groovy, JavaScript (Rhino) and Velocity template for generating representation. User creates the template script as a resource and refers then in the content type definition. Clients are provided URI's to the representation from the content generic media formats (Atom XML, JSON) and upon fetching them receives the output generated by the script. I am tempted to take a similar approach for your problem. It would not only separated the UI from the business objects, but also provide flexibility to add new backend services in the long run.
As tools for RESTful WS over Java I would recommend, Jersey, Abdera, Jackson. As an example for how use them together you can have a look at the CMS project I was referring to.
Hi i would suggest you to build your system with a modular approach such that
you have all your business logic is exposed as a service which can be accessed by REST,
in addition create you can have web application layer and a desktop layer.
schemantically it will look like be at a higher level
weblayer/desktop---------{REST interface} ------- {business logic}-----EIS
and for modularisation you can consider OSGI
hope this helps
I'd like to learn how to create a java web service that can be consumed by a web tier, which is constituted of java and flex.
What books can help me learn how to create a java web service and consume it via java & flex?
Should I look to build a web service from scratch or from frameworks like: XFire, Axis, CXF, Spring Web Services, etc.?
If using a framework is recommended, which of the above or any others makes the most sense to learn/use?
EDIT:
Both the java AND flex components of the web tier need to independently access the web service. For example, the flex component helps the user create & save a spreadsheet; the java component retrieves the spreadsheet data and displays it accordingly.
Flex should do the job: Web Services with Flex tutorial
You may not need a web service. Your Flex app can consume Java POJOs directly using Spring and BlazeDS.
What kind of a service are we looking at? If it requires database integration you probably need at least some kind of a framework - you really don't want to be putting your SQL queries hard coded into the app. Spring + Hibernate seems to be one of the most popular choices for a Java server implementation, but both of them are quite massive and require some effort. Appfuse could be something that provides a good starting point for building a service.
Why do you want to do your service with Java anyway? Is this because you know only Java or because there is a Java container already running on your server? I've seen great results with Ruby on Rails too and now there's some buzz about Scala too in the Java world. This could be your chance to try out something new and more flexible ;)
I'll take this opportunity to plug my own book, Eclipse Web Tools Platform: Developing Java Web Applications. Chapter 10 deals exclusively with creating Java Web services. Although the examples are all shown using WTP tooling the lessons discuss Java Web services created with Apache Axis.