Develop Reference

How to create a java client for a Spring service?

I have a service definition using Spring annotations. Example (source):
#RequestMapping(value = "/ex/foos/{id}", method = GET)
#ResponseBody
public String getFoosBySimplePathWithPathVariable(
#PathVariable("id") long id) {
return "Get a specific Foo with id=" + id;
}
The question is whether spring (or another library) can auto-create a remote implementation (client) of the same API without the need to manually type paths, method type, param names, etc. (like needed when using RestTemplate)?
Example of an such a client usage:
FooClient fooClient = new FooClient("http://localhost:8080");
String foo = fooClient.getFoosBySimplePathWithPathVariable(3l);
How can I get to such a client "generated" implementation"?

You are probably looking for Feign Client. It does everything you need: calling one service via HTTP is similar to calling method of Java interface. But to make it work you need Spring Cloud, standard Spring framework doesn't have this feature yet.

You can generate it using Swagger Editor. You shoud just define the path of the resources and then it'll generate for you the client for almost any language of your choice

wsdl file location path setup in java

I'm using wsdl files to generate client & is working fine on my local server since the generated files have path like "C:\path\to\wsdl\Air.wsdl"
I'm trying to replace all the paths as above to the one that work on live server I've found some hints but I'm not so sure how to implement it (I'm new to web services).
Below is how my files currently look like
#WebServiceClient(name = "AirService",
wsdlLocation = "file:/C:/Eclipse WorkSpace/TravelPortCXF/WebContent/wsdl/air_v33_0/Air.wsdl",
targetNamespace = "http://www.travelport.com/service/air_v33_0")
static {
URL url = null;
try {
url = new URL("file:/C:/Eclipse WorkSpace/TravelPortCXF/WebContent/wsdl/air_v33_0/Air.wsdl");
} catch (MalformedURLException e) {
java.util.logging.Logger.getLogger(AirService.class.getName())
.log(java.util.logging.Level.INFO,
"Can not initialize the default wsdl from {0}", "file:/C:/Eclipse WorkSpace/TravelPortCXF/WebContent/wsdl/air_v33_0/Air.wsdl");
}
WSDL_LOCATION = url;
}
This seems to be like it should be changed (I'm not sure about that, found it on googling)
#WebServiceClient(name = "AirService",
wsdlLocation = "classpath:wsdl/air_v33_0/Air.wsdl",
targetNamespace = "http://www.travelport.com/service/air_v33_0")
static {
URL url = AirService.class.getClassLoader().getResource("wsdl/air_v33_0/Air.wsdl");
if (url == null) {
java.util.logging.Logger.getLogger(AirService.class.getName())
.log(java.util.logging.Level.INFO,
"Can not initialize the default wsdl from {0}", "classpath:wsdl/air_v33_0/Air.wsdl");
}
WSDL_LOCATION = url;
}
But I actually don't understand how that method works.. Can someone please make me understand how can I change the path and where to place the wsdl files in the project so that it works properly on the live server and also the difference between both the codes.
Also I don't want to generate every-time when build is created, I want to generate the files (that are already been generated), place the wsdl somewhere in the project folder from where it can be accessed and then change the path in the Java files (by replacing all the paths at once) as in the above codes.

Few intro points for you:
Wsdl file contains description webmethods callable on the server (in general method names, their input parameters and its types and types of results of this methods). Therefore wsdl file is like contract between client and server - client knows what methods to call on the server, what parameters it will need to send with method name, and what type of result it can expect.
You can download and store wsdl file from server, and then use it for generation of special client class(es) (called stubs). This classes have java methods 1 to 1 corresponding to web service methods described in wsdl file. Source code of these classes is generated automatically by special tool (wsimport) which reads content of wsdl file and generate corresponding methods. From your perspective as developer of client, it is then very simple - you need only in some way create instance of this class (giving it url of wsdl file on the server) and call it's method like you call any other Java class method. (Generated implementation code of this methods cares for serialization of inputs and sending of webservice request to server, and then deserialization of response back to you, so you will obtain normal Java object as a result of call).
Maybe you now ask, why you need to set url to server's wsdl file before call of webservice method. Answer is that client code before calling your webservice automatically download's wsdl from the server and check's if it does not change meantime (if yes it does not call webservice and throws error). It sometimes happen that developer of server changed e.g. parameters of webservice method and you as client developer have still old version of wsdl, therefore validation aspect of this technology saves you a lot of time.
Now real examples:
Look at JAX-WS deployment best practice: WSDL location and client generation question to see client code how webservice method (hello) is called using HelloWorldPOCImpl stub class.
For server side implementation you need only two annotation #Webservice and #WebMethod, please look at chapter 3.1 to see example: https://metro.java.net/getting-started/building-a-simple-metro-application.html
For server, you dont need to create wsdl file manually, server generates wsdl file automatically - based on your code and mentioned annotations.

How do I support localization with Jersey?

I am designing a REST API that I would like to be localizable in the future.
Therefore I am defining the URLs to be of the form
/en/<resource_url>
With the intention of being able to support
/fr/<resource_url>
In the future if need be.
However I only want to define each resource url service once. Therefore I figure I need to get the URL parsed and rewritten without the language piece of the URL before it is matched to services. Finally that language should be made available to the services somehow for them to localize if necessary.
How can I achieve this?
I am using Jersey 1.17 inside Jetty container embedded in a larger server process.

You can make the /en/ or the /fr/ part a variable. Then set your locale to the value of the variable. Here's an example:
#Path("/{locale}/username")
public class UserResource {
#GET
#Produces("text/xml")
public String getUser(#PathParam("locale") String locale) {
...
}
}
But that may not be the best way to go about it. After answering, I found this other SO question that is a better way to solve the problem: Getting the client locale in a jersey request With this way, you don't need to add this to the URL. Just make the client set a header.

How to start GWT from web service REST

Is it possible to run GWT application from web service REST?
#Path("/main")
public class RestService {
#GET
#Path("{name}")
public Response getUserByName(#PathParam("name") String name){
// return Response.status(200).entity("My name is " + name).build();
}
}
What is important for me, the URL which calls REST, must not be changed after GWT will run. So when the browser go to localhost:8080/application/main/adam, the REST runs and calls the GWT application which shows message box with My name is adam. After that, I can sill see the same URL in the browser.
Maybe I should explain the reason of my requirements.
I want to create application where the end-user will use only the URLs, example:
localhost:8080/application/somecommand/somedata
localhost:8080/application/anothercommand/anotherdata
No windows, no forms, only URLs.

Yes, it is possible. Just serve the HTML page with your GWT app.

If you can deal with Urls Like this:
localhost:8080/application#somecommand/somedata
localhost:8080/application#anothercommand/anotherdata
It is just the GWT History-API

Axis2 Web Service Client Generation - Types without modifying the client

Is it possible with Axis2 and Eclipse to generate a Web Service client and have it use java types that you already have in packages instead of creating it's own types. Reason being of course if I have type A already created and it creates it's own Type A I can't just assign variable of type A to variable of type B.
The wsdl is being generated from a Web Service deployed to an application server.
If it's not possible to generate it from that would it be possible to generate a client from the already existing java files.

If you really want to reuse existing classes, you can call the Axis2 API directly without generating a client using wsdl2java. Below is some relatively simple code to call a web service. You just need to fill in the web service endpoint, method QName, expected return Class(es), and arguments to the service. You could reuse your existing classes as the return values or arguments.
If your web service is pretty complicated then you may find that you have to go deeper into the API to get this approach to work.
serviceClient = new RPCServiceClient();
Options options = serviceClient.getOptions();
EndpointReference targetEPR = new EndpointReference("http://myservice");
options.setTo(targetEPR);
QName methodName = new QName("ns","methodName");
Class<?>[] returnTypes = new Class[] { String.class };
Object[] args = new Object[] { "parameter" };
Object[] response = serviceClient.invokeBlocking(methodName, args,
returnTypes);

You are generating the web service client from wsdl, correct?
The only thing that the wsdl2java tool knows about is the information in the wsdl, so it won't know about any types that you have already created.
If you can get the type information into the wsdl you may get it to work, although I have never tried.
If you want an easy way to copy from Type A to Type B then you could try BeanUtils.copyProperties, as long as the setters and getters of Type A and Type B match.

pretty much most java webservices projects go through this. I don't know if the .NET/C# world have a more elegant solution.
It makes sense, as Mike mentioned, to use BeanUtils.copyProperties.
BR,
~A

If you use eclipse as your ide, that is waht you need: http://www.eclipse.org/webtools/. It does beyond other things exactly what you want.

You can directly use ServiceClient class to call web service, which provides call using XML only and returns XML response. For different methods of web service, you have to convert the XML response to some java POJO to use it. Only Response handling needs to be done at your end. that you can do like from XML to Map etc...
So you won't need any other stub classes to call any web service, only needs to handle response XML. You can convert XML to POJO using Castor or JAXB libs.
This is the way you don't need to modify your client every time for diff. web services. You can develop like providing a response handler to client externally. So that for every different web service you will have diff. response handler class which is implementation of you interface.
//common interface for response handlers...
//implement this for diff. web service/methods
public interface WSRespHandler{
public Object getMeResp(Object respData);
}
//pass particular handler to client when you call some WS
public class WebServiceClient {
public Object getResp(WSRespHandler respHandler) {
..
return repHandler.getMeResp(xmlData);
}
}
reference:
http://www.developer.com/java/web/article.php/3863416/Using-Axis2-and-Java-for-Asynchronous-Web-Service-Invocation-on-the-Client-Side.htm
http://www.devdaily.com/blog/post/java/java-web-service-client-read-array-list/
thanks.
www.techlads.com

In case this post is still of any use to someone I read the axis2 generating clients guide: http://axis.apache.org/axis2/java/core/docs/userguide-creatingclients.html.
It seems that the Axis2 Eclipse plugin is configured to call ADB code generation in integrated mode (see http://axis.apache.org/axis2/java/core/docs/adb/adb-howto.html), thus creating inner classes in the Web service stub. I don't know if changing the generation mode to expanded mode (generate data classes out of the stub class) is possible, but you can do it command line using Wsdl2Java:
%AXIS2_HOME%\bin\WSDL2Java -uri <wsdl file path> -p <package name> -u
The -u option tells the ADB code generator to create data classes as separate classes and not inner classes in the stub.