Provided a WSDL I create a dynamic web service client. What I want is to expose the methods and the types of the parameters those methods have and test the code from a webpage. Bare in mind that the client is dynamic, so what I have to build must me able to work with different WSDLs.
What I want to do is what the Eclipse web service explorer does for testing a web service client from the provided user interface. How does it find the methods and the parameters? Does it parse the WSDL? I've searched for the source code, but I couldn't find anything relevant. I don't even know where to begin.
What I want is suggestions and some guidance of what I have to build, what is already provided out there (that I'm not aware obviously) and a place to begin. I'm not asking for code.
Essentially creating a generic web services client would involve the following:
Analyse the WSDL for service definitions i.e. the method names and their definitions. Remember your WSDL defines your service.
Analyse any XSD (embedded or linked) to retrieve the datatypes of the parameters etc.
As a suggestion why not look at the SOAP UI project which is really great as a generic web service test client. As it is open source you might be able to learn how they do it. Go have a look at the project here
Also go look at the Apache CXF framework. This framework will allow you to easily create a webservice client. See this tutorial for more information: how to create a client in CXF. CXF is also usable via javascript so it might be what you are looking for see this link
I would suggest that you try leveraging these tools before you try to invent one yourself as parsing WSDL's and XSD while NOT difficult to parse it going to take a substantial programming effort. CXF already has this covered for you if I read your question right.
Related
I am new to Java GUI, I have knowledge of core Java.
I have to call a REST client from my NetBeans project, give values to it, and receive its output in the same project.
Please point me to some helpful resources.
This tutorial covers the basics using Twitter's REST api which should be stable enough for you to be confident that any errors you see are in your implementation and not the API.
"In this tutorial, you create a NetBeans platform application that consumes the Twitter What Are You Doing service, displaying a list of your Twitter friends' status messages. First you create the platform application. You select the libraries needed in the application. Then you create a NetBeans module. Finally, you add a RESTful client and some basic display elements to the module. The client uses OAuth authorization."
https://netbeans.org/kb/72/websvc/jersey-rcp-client.html
You could try looking at the Oracle documentation on JAX-RS clients, which is how you can access REST resources using Java.
http://docs.oracle.com/javaee/7/tutorial/doc/jaxrs-client.htm
In addition, client libraries like RestEasy and Jersey can help make your life even easier.
When dealing with RESTful webservices, you'll also want to know how the request bodies map to your Java objects. Are you using XML, JSON, a combination? It will help to know that as well so that you know if you need an XML mapping framework or a JSON mapping framework. You can just parse the strings, but depending on how complex it is, that might get really messy!
I don't know much about the J2EE/Web Project in Java.
Actually the thing is like that I have git some projects (10-12) inter-related with each other (contains lots of packages, classes, etc). And it requires JBOSS server to run the complete project.
I am confused after seeing some little bit code of it. When I tried to run it using JBOSS server then it opens a link in the browser.
I want to know that actually where the web service is present in the project so that I can come to know the little bit by bit things.
Sorry for asking idiot question.
Please advice.
Thanks
Have a look at the web.xml file of the Project.
It will give you a head start.
Bhavesh.. Firstly you should know which type of webservice has been developed in your project. Either REST or SOAP service.
Second thing you should know that on which library or technologies your web service built on.
for example REST based service can be developed by using Jersey or Spring MVC (in this case you can find some annotation like #RequestMappling or #GET).
SOAP based web-services commonly contain WSDL file and some .XSD (in case of contract first webservice) file.
Being without specific information it is pretty hard to tell about where is your web-service part in project.
Web services are used to share the services provided by an application, to outside world. This is my basic understanding of web services.
Suppose my application is to expose some specific behaviors and I have written the code for it and exposed the methods. The ones who want to use it can take the link to the wsdl, generate stub and call the methods.
What is the use of doing all this, when I can myself expose the methods, generate a jar and bundle everything in it and share the server address,jar.
How differently is web services important, when compared to a case explained above. Am asking such a general question due to unsuccessful search in many websites.
If you'd generate a client jar, whoever wants to use that would have to deal with Java. If you expose a Web Service instead, the user can use whatever technology he/she wants to use (e.g. Python, Ruby, .net, C, C++ etc. etc.). That would be a huge advantage.
Web service use a series of standards(SOAP, WSDL...) to make different kinds of system work together, certainly you can generate client jar as you like, but that requires your service consumer to learn how to play with it, so it's not a generic solution.
What you are suggesting is quite close to RESTful webservices. Unlike SOAP webservices, RESTful webservices do not require any WSDL files. All that you need to do is to issue a request to a particular URL.
As you explained correctly (in my opinion) SOAP webservices involve some more work which needs to be done, thus making them more complex, if you will, to integrate with other systems. This is not the case with RESTful webservices.
EDIT: You can check out a tutorial here. I have tried it myself a while back and it is enough to get you started.
I have a project coming up that will require me to call a SOAP web service from my java application. I'm wondering what toolsets I should look at to do this? All advice appreciated.
I've looked at jax-ws and Axis2 but these appear to be mostly for creators of web services instead of consumers and I only wish to consume.
Thanks!
First of all you need wsdl. Some service providers might distribute Java client classes, but WSDL is the safest approach.
Once you have it, run tool like wsdl2java for apache-cxf or analogous in apache-axis against it. It will create a bunch of Java classes (you only need the client side). These tools are also capable of generating server-side code, hence the impression you had that they aim service developers.
This is all you need - the client classes will handle XML marshalling/unmarshalling and HTTP connectivity for you. Just use appropriate stub implementing WS endpoint interface.
You can also use WebServiceTemplate from spring-ws portfolio.
Jax-WS comes with a tool called wsimport which you run against the .wsdl of the SOAP service. It generates a whole bunch of classes your client can use to interact with the service. After that it's just plain Java coding.
If you are using eclipse you may want to view this solution:
What is the easiest way to generate a Java client from an RPC encoded WSDL
If you want a rapid-functional client you can use JAX-WS tools to generate the code that you need to consume a Web Service. But sometimes this approach can generate non-portable code (like with Websphere tools) but you the productivity gain maybe worth it.
Spring Framework also offers tools to build and consume web services, but it requires some extra effort to develop the client and it may require some manual mapping of the input/output messages with technologies like JAXB or Castor. You can also directly read XML with Spring, it's a flexible framework that assures you portability between containers but it requires extra effort and time.
Every approach has it pros and cons. It's up to you to decide.
I need to write a web service client in Groovy. The author of the web service has proposed various unappealing blobs of Java code that I could use to call the service from my Grails application.
At this point, I think it might be better if I just ask them to give me the WSDL and I'll take care of the client code myself. I'm looking for suggestions about the best way to go about writing a Groovy web service client using only a WSDL document?
I expect most suggestions will involve using some tool to generate a client-side API that I'll call from my Grails app. If so, then it's important that I can integrate generation of this API into a Grails build, because the WSDL document will probably change frequently.
I've looked at using GroovyWS which provides a very simple way of calling web services. However, it seems to lack any concept of a contract which concerns me from the point-of-view of testing. I would like to define a contract (interface) for the web service, for which I provide a real implementation that the app will use and a mock implementation that my unit tests will use.
Given your desire for more stability than the very dynamic GroovyWS, I'd suggest the easy way:
Use JAX-WS to generate a Java client, compile that and use it from Groovy. It's all statically typed and the generate Java source is reasonably clean (definitely much better than older WS client frameworks such as Axis 1).
Of course that would require that you have access to the WSDL.