Make simple web service

Question

Hi all, I'd like to make simple web service. I made a desktop (swing) application, which requires access to database. The database is not accessible from outside of the server.
But I have web application on this server, so I can create a servlet (or jsp), which could operate as web service. Afterwards I can create a connection in my desktop application directed to this service page. The page downloads required data and grants them for my desktop application.
But I don't know the way I could do it. Can you help me please? Thank you :-).

Answer 1

Hi again, after several days, I'm back. It seems to be very good solution for me, but I have a problem. I can't catch it :-(. I've read the manual pages maybe twenty-times and I've looked for another tutorials and so on. Nothing helped. I don't know, how I can run it :-(. I create following:
My web.xml:<web-app version="2.4"
           xmlns="http://java.sun.com/xml/ns/j2ee"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
           http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
     <servlet>
          <servlet-name>EOTService</servlet-name>
          <servlet-class>services.EOTService</servlet-class>
          <init-param>
               <param-name>enabledForExtensions</param-name>
               <param-value>true</param-value>
               <description>Sets, whether the servlet supports vendor extensions for XML-RPC.</description>
          </init-param>
     </servlet>
     <servlet-mapping>
          <servlet-name>EOTService</servlet-name>
          <url-pattern>/service</url-pattern>
     </servlet-mapping>
</web-app>In package services I have two .java files. The first one, Calculator.java:package services;
public class Calculator {
     public int add(int a, int b) {
          return a + b;
     public int sub(int a, int b) {
          return a - b;
}and the second one, EOTService.java:package services;
import org.apache.xmlrpc.*;
import org.apache.xmlrpc.common.*;
import org.apache.xmlrpc.server.*;
import org.apache.xmlrpc.webserver.*;
public class EOTService extends XmlRpcServlet {
     private boolean isAuthenticated(String pUserName, String pPassword) {
          return pUserName.equals("username") && pPassword.equals("password");
     protected XmlRpcHandlerMapping newXmlRpcHandlerMapping() throws XmlRpcException {
          PropertyHandlerMapping mapping = (PropertyHandlerMapping) super.newXmlRpcHandlerMapping();
          AbstractReflectiveHandlerMapping.AuthenticationHandler handler =
               new AbstractReflectiveHandlerMapping.AuthenticationHandler() {
                    public boolean isAuthorized(XmlRpcRequest pRequest) {
                         XmlRpcHttpRequestConfig config = (XmlRpcHttpRequestConfig) pRequest.getConfig();
                         return isAuthenticated(config.getBasicUserName(), config.getBasicPassword());
          mapping.setAuthenticationHandler(handler);
          try {
               mapping.addHandler("Calculator", Class.forName("services.Calculator"));
          } catch (ClassNotFoundException e) {
               e.printStackTrace();
          return mapping;
}In the myapp/WEB-INF/lib I have these files:xmlrpc-common-3.1.3.jar
xmlrpc-server-3.1.3.jarAnd now, I'd like to connect to this servlet and download data. So I have another application and in main method of the application I call this:public static void main(String[] args) {
try {
            XmlRpcClientConfigImpl config = new XmlRpcClientConfigImpl();
            config.setServerURL(new URL("http://127.0.0.1:8080/service"));
            XmlRpcClient client = new XmlRpcClient();
            client.setConfig(config);
            Object[] params = new Object[]{new Integer(33), new Integer(9)};
            Integer result = (Integer)client.execute("Calculator.add", params);
            System.out.println("33 + 9 = " + result);
        } catch (java.net.MalformedURLException e) {
            System.out.println(e.getMessage());
        } catch (org.apache.xmlrpc.XmlRpcException e) {
            e.printStackTrace(System.out);
}But following exception is thrownException in thread "main" java.lang.NoClassDefFoundError: org/apache/ws/commons/serialize/DOMSerializer
        at org.apache.xmlrpc.serializer.NodeSerializer.<clinit>(NodeSerializer.java:30)
        at org.apache.xmlrpc.common.TypeFactoryImpl.<clinit>(TypeFactoryImpl.java:88)
        at org.apache.xmlrpc.common.XmlRpcController.<init>(XmlRpcController.java:31)
        at org.apache.xmlrpc.client.XmlRpcClient.<init>(XmlRpcClient.java:51)
        at main.Main.main(Main.java:51)
Caused by: java.lang.ClassNotFoundException: org.apache.ws.commons.serialize.DOMSerializer
        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
        ... 5 moreI'm trying to implement it for five days and my failure is very stressful. Help me please... please :-[.