Interfaces/SOAP Web Service

We will show how to make J component available as a web service and consume it with a .NET client here, as well as a Mac SOAP Client or J SOAP Call.

Exposing J Service

Here we will see how to expose J component as a SOAP web service without writing any code, just configuring Windows Component Services.

Creating COM+ Application

Here we will expose J.dll as a COM+ application. To learn more about various selection user the [?] title button and point the mouse to the option of interest.

COM+ Application-Container

See also Creating a New COM+ Application, MSDN
Launch Component Services from Administrative Tools
Locate Component Services / Computers / My Computer / COM+ Applications
Right-click COM+ Applications, New / Application
In the wizard, select Next, Create Empty Application
Give it a name JApp
Leave Application Type as Server Application
Select Next, Next, Finish

J Component

See also Installing New Components, MSDN
Under JApp, right-click Components, select New Component
Select Next,
- select Import... to choose registered JDLLServer.3, or
- select Install new component and choose j.dll as a file
Select Next, Finish

Now JApp is ready to be consumed as a COM+ component.

SOAP Service

See also Creating XML Web Services (COM+), MSDN
Right-click JApp, select Properties
In Activation tab, check [X] Uses SOAP
In SOAP VRoot, give it a name, e.g. JApp

Navigate to http://localhost/JApp/ so see the wsdl interface of JDLLServer component.

Consuming J Service

Now we will create some client applications to consume the SOAP service.

.NET Web Service Client

Adding Web Reference

In Visual Studio, select File / New / Project
Visual C#, Console Application, select location and name JSoapClient, click OK
From menu, select Project / Add Web Reference
Paste http://localhost/JApp/ into URL, select Go, select JDLLServer...
In Web reference name, enter Local_JApp, click Add Reference

To verify, in Solution Explorer, under Web References, double-click Local_JApp to see the interfaces in Object Browser. The JDLLServerClassService is the one we are going to work with. There are other interfaces to do async calls, etc.

Calling Web Service

At the top of the Program.cs source enter using reference, intellisense is helping here {{{using JSoapClient.Local_JApp;

}}}

The web service must be disposed after use, so we create it
with using construct or must call .Dispose() safely {{{using (JDLLServerClassService jsvc = new JDLLServerClassService()) {
- .. // the code

} }}}

Now let's do some J calls. In Object Browser, method DoR has signature
public int DoR(string input, out object v), so we have
```
    object result;
    jsvc.DoR("i.2 3", out result);
    Console.WriteLine("   i.2 3\n{0}", result);
```
Now run it and see the result

i.2 3
0 1 2
3 4 5

If we define a name,

    jsvc.Do("a=: i.2 3");
    jsvc.DoR("+/ a", out result);
    Console.WriteLine("   +/ a\n{0}", result);

we will lose its definition

+/ a
+/ a

This is because the Web Service is activated in the SingleCall mode. To change that open C:\WINDOWS\system32\Com\SOAPVRoots\JApp\Web.config and change <wellknown mode="SingleCall" to "Singleton", and save it.
Now the same construct will retain the name definition

+/ a
3 5 7

Java Web Services Client

Since J component is exposed as a web service it would be possible to consume it from different machines using any language that can call SOAP web services, or even just can make an HTTP request.