Practical introduction to Web Service and Interoperability using ASP.NET Web Matrix and AXIS 1.1
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In this article we will check how .NET and Java can talk to each other using web services. Again I will assume that the reader of this article is not in a position to afford high-end tools that involve significant financial commitments. I will also assume that the reader of this article uses Windows 2000 or Windows XP Professional as operating system. So what do we need for the start? From .NET side we will need .NET Platform SDK and ASP.NET Web Matrix. Maybe the best place to get those is www.asp.net, there you will find all the information about download and installation process. If you are using dial-up (like me) then paying a visit to local Microsoft and exploring the possibility to get .NET Platform SDK on CD is a good idea. If you happen to be in possession of VS.NET then you already have .NET Platform SDK and you can use VS.NET instead of ASP.NET Web Matrix. From Java side the list is longer but download is altogether smaller. First we need JavaTM 2 SDK, Standard Edition, that could be downloaded from http://java.sun.com/j2se/1.4/, when we are at Sun Microsystems web site we may download also JavaTM Web Services Developer Pack, the link is here http://java.sun.com/webservices/downloads/webservicespack.html. WSDP contains Tomcat and lot of other goodies which we are going to need later to make Axis feel at home on our machine. The story about visiting local Sun branch and exploring the possibility of getting those two on CD is certainly an option here. Finally, we will need Axis and for its WSDL tools crimson. For those two we will look at http://xml.apache.org/axis and http://xml.apache.org/crimson/. At the moment of writing this article Axis 1.1 RC2 is the latest available binary download. If you are still in the mood for more downloads there is a number of free IDE for Java which you may wish to try, like :

- NetBeans IDE 3.5 http://www.netbeans.org/
- Eclipse 2.x http://www.eclipse.org/
- jEdit 4.x http://www.jedit.org

to name a few. Free IDE for .NET which is very good is SharpDevelop and it could be found here http://www.icsharpcode.com/. If you had enough of downloading, don't worry, simple text editor and command line approach is something you can always rely on.

Installing all that on Windows

So you got .NET Platform SDK, webmatrix.msi, jwsdp-1_1-windows-i586.exe (or later), j2sdk-1_4_1-win.exe (or later), axis-1_1rc2.zip and crimson-1.1.3-src.zip (or bin). All that comes in form of exe or msi file is associated with wizard which will guide you through installation process. Accept defaults and consistently choose Next until you are done. Prior to installation of .NET Platform SDK be sure that you have IIS installed. In our exercise we won't use IIS at all, so when you are done with installation you can shut it down. If you encounter any difficulty during installation of any of those feel free to ask Microsoft or Sun for advice, they have FAQ-s and forums dedicated to their products where answers to most commonly encountered problems can be found. Now we may check how Tomcat and ASP.NET Web Matrix WebServer.exe work. Don't try them together because both of them are using http://localhost:8080 by default. To start WebServer.exe we could open ASP.NET Web Matrix IDE, create some hello world web page and press F5. It will show Start Web Application dialog where you can pick parameters like directory or port number. If you are happy with suggested parameters select Start button and WebServer.exe will start with work. To move WebServer.exe to a different port execute from command line WebServer /port:9090 /path:"C:\Inetpub\wwwroot\testws2" /vpath="/testws2", if that is where your preferred virtual directory is and port 9090 is port which you would like to use. Also, you can configure it from ASP.NET Web Matrix using GUI when you press F5. To start Tomcat we need to execute startup.bat which is typically in C:\Documents and Settings\Administrator\jwsdp-1.1\bin directory if you are logged in as Administrator and you are using WSDP 1.1. If you are planning to spend some time with Tomcat you will find out that C:\Documents and Settings\Administrator\jwsdp-1.1 is also called CATALINA_HOME. Give some time to Tomcat to start and point browser to http://localhost:8080. If there is index page Tomcat is up and running. To move Tomcat to another port open C:\Documents and Settings\<How you are known to your computer>\jwsdp-1.1\conf\server.xml in text editor and search and replace 8080 with desired port value. Be sure that all 8080 entries are replaced with new value. That is under condition that you are using WSDP 1.1, if you are using another WSDP version change jwsdp-1.1 to jwsdp-1_0, jwsdp-1.2 or whatever it may be in your case. Now we need to install Axis. While building crimson is not too difficult (and Ant is included in WSDP) I would advise to get Axis as binary distribution. Unpack axis-1_1rc2.zip somewhere, for example into D:\axis-1_1rc2. There are two main ways how Axis could be installed on Tomcat. The first is : locate D:\axis-1_1rc2\webapps\axis and copy it to C:\Documents and Settings\Administrator\jwsdp-1.1\ webapps. Start Tomcat and point browser to http://localhost:8080/axis, you should see Axis welcome page. The other way is to edit C:\Documents and Settings\<How you are known to your computer>\jwsdp-1.1\conf\server.xml and create Context for Axis. The simplest is to locate admin context and to looking at it create axis context, something like this :

<Context className="org.apache.catalina.core.StandardContext" 
   crossContext="false" reloadable="false" 
   mapperClass="org.apache.catalina.core.StandardContextMapper" 
   useNaming="true" debug="0" privileged="true" 
   wrapperClass="org.apache.catalina.core.StandardWrapper" 
   docBase="D:/axis-1_1rc2/webapps/axis" cookies="true" path="/axis" 
   cachingAllowed="true" 
   charsetMapperClass="org.apache.catalina.util.CharsetMapper">
   <Logger className="org.apache.catalina.logger.FileLogger" 
      debug="0" verbosity="1" prefix="localhost_axis_log." 
      directory="logs" timestamp="true" suffix=".txt"/>
</Context>

<%@ WebService language="C#" class="InteropHW" %>

using System;
using System.Web.Services;
using System.Xml.Serialization;

public class InteropHW {
   [WebMethod]
   public int ArrLength(int[] a) {
      return a.Length;
   }
}

public class JInteropHW {
   public String[] getArr(int l) {
      return new String[l];
   }
}

//     Changes to this file may cause incorrect behavior and will be lost if 
//     the code is regenerated.

public JInteropHWService() {
   this.Url = "http://localhost/axis/JInteropHW.jws";
}

static void Main(){
   JInteropHWService jhw = new JInteropHWService();
   Console.WriteLine(jhw.getArr(9).Length);
}

set AXIS_HOME=D:\axis-1_1rc2
set JWSDP_HOME=C:\Documents and Settings\Administrator\jwsdp-1.1

set CLASSPATH=.;%AXIS_HOME%\lib\axis.jar;%AXIS_HOME%\lib\axis-ant.jar;%AXIS_HOME%\lib\commons-discovery.jar;

%AXIS_HOME%\lib\commons-logging.jar;%AXIS_HOME%\lib\jaxrpc.jar;%AXIS_HOME%\lib\saaj.jar;%AXIS_HOME%\lib\crims

on.jar;%AXIS_HOME%\lib\wsdl4j.jar;%AXIS_HOME%\lib\log4j-1.2.4.jar;%JWSDP_HOME%\jaxp-1.2.2\lib\endorsed\dom.ja

r;%JWSDP_HOME%\jaxp-1.2.2\lib\endorsed\sax.jar;%JWSDP_HOME%\jaxp-1.2.2\lib\jaxp-api.jar

public class InteropHWClient
{
   public static void main(String [] args) {
      try {
         org.tempuri.InteropHW il = new org.tempuri.InteropHWLocator();
         org.tempuri.InteropHWSoap i = il.getInteropHWSoap();
         org.tempuri.ArrayOfInt ip = new org.tempuri.ArrayOfInt();
         ip.set_int(new int[5]);
         System.out.println("Length of array is " + i.arrLength(ip));
      } catch (Exception e) {
         e.printStackTrace();
      }
   }
}