Tomcat & XML-rpc

[Joe Schaffer]

Hi everybody,

Actually I have some problems to understand the real requirements for the XML-RPC. What I later on want to do is to transport information in an XML format and transform them on my server into SQL data for further tasks.

The simple program I am looking for is the Servlet Class - HelloServer. This contains the doPost/doGet functions. Accessing this should be performed by a commandline call "java HelloClient" .

The client should then trigger a "System.out.println" on the Server Side which will be displayed in the Tomcat server window. I think this should only be a few lines. My actual code is the following:

HelloHandler.java:

 public class HelloHandler {

public String sayHello(String name) {
return "Hello " + name;
}
} 

HelloServer.java

  import org.apache.xmlrpc.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.OutputStream;
import java.io.*;
 
public class HelloServer extends HttpServlet{
 
private XmlRpcServer xmlrpc;
 
public HelloServer (XmlRpcServer xmlrpc){
this.xmlrpc=xmlrpc;
System.out.println("create hello Handler");
this.xmlrpc.addHandler("hello", new HelloHandler());
}

public void doGet(HttpServletRequest req, HttpServletResponse res) 
throws ServletException, IOException {
doPost(req,res);
}

public void doPost (HttpServletRequest req, HttpServletResponse res) 
throws ServletException, IOException {
try{
xmlrpc.addHandler("hello", new HelloHandler());
 
}
catch (Exception e){
System.out.println("Error: "+ e);
}
try{
byte[] result = xmlrpc.execute(req.getInputStream()); 
xmlrpc.execute (req.getInputStream());
res.setContentType("text/xml");
OutputStream output = res.getOutputStream();
output.flush();
}
catch (IOException e){
System.out.println("Error: "+ e);
}
}
}

HelloClient.java

 
import org.apache.xmlrpc.*;
import java.util.*;
public class HelloClient {

public static void main(String args[]){
 
Vector params = new Vector();
params.addElement("World");
 
try {
System.out.println("create request");

//???Can I check if this was successful????????
XmlRpcClient client = new XmlRpcClient("http://localhost:9090/HelloServerServlet/servlet/HelloServer");

System.out.println("create request done");
 
//!!!An error occurs by calling this command!
String result = (String) client.execute("hello.sayHello", params);
System.out.println("execute done");
System.out.println("Response from server: "+ result);
}
catch (Exception e){
System.out.println(e);
};
}
} 

My Error Message is on the HelloClient command line:
java.io.IOException: Werver returned HTTP response code: 500 for URL: http://localhost:9090/HelloServerServlet/servlet/HelloServer

On the tomcat side I get
- Ctx(/HelloServerServlet) : Exception in preInit HelloServer - java.lang.InstantiationException: HelloServer
at java.lang.Class.newInstance0(Class.java:293)..... There is none of my classes mentioned! Mentioned are Class, ServletHandler, ContextManager, Tomcat3Adapter, Http11Processor, Http11Protocol, PoolTcpEndpoint, ThreadPool, Thread all have the .java ending

Thx for your help

Regards

Joe

[William Brogden]

1. Put your servlet class in a package
2. create the correct web.xml for your application, specifying the servlet class and the url-mapping you will be using.
3. Read this FAQ entry on the invoker servlet to understand why you should NOT be using a URL with /servlet/ in it.
Bill

[Joe Schaffer]

Hi,

Thanks for your help. I additionally found an error in my code. I haven't initialized the XML-RPC

THis is missing in the server:

 public void init (ServletConfig config) throws ServletException   {      
      xmlrpc = new XmlRpcServer();
      xmlrpc.addHandler("hello", new HelloHandler());
      System.out.println("Debug: RCMConnector.init - initialization done");
 
}  

Regards

Joe