Group,

I'm getting an HTTP 500 Status error using Apache Tomcat.  I'm
learning Servlets and JSPs from the Head First book.  I've searched
the groups and on the Internet, and can't seem to resolve my problem.

I have a webpage, form.html, that displays just fine with http://
localhost:8080/beer-V1/form.html.  This web page is mapped in web.xml
to /BeerSelect.do:

- <servlet>
 <servlet-name>Ch3 Beer</servlet-name>
 <servlet-class>com.example.web.BeerSelect</servlet-class>
 </servlet>
- <servlet-mapping>
 <servlet-name>Ch3 Beer</servlet-name>
 <url-pattern>/SelectBeer.do</url-pattern>
 </servlet-mapping>
 </web-app>

BeerSelect.do maps the BeerSelect servlet class, which controls the
BeerExpert model.

BeerSelect:
package com.example.web;

import com.example.model.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;

public class BeerSelect extends HttpServlet {

    public void doPost(HttpServletRequest request, HttpServletResponse
response)
                throws IOException, ServletException {

        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        out.println("Beer Selection Advice<br>");
        String c = request.getParameter("color");

        BeerExpert be = new BeerExpert();
        List result = be.getBrands(c);
        Iterator it = result.iterator();
        while (it.hasNext()) {
            out.println("<br>try: " + it.next());
        }
    } //end doPost
} //end class

is stored in C:\Apache\Tomcat6\webapps\beer-V1\WEB-INF\classes\com
\example\web\BeerSelect.class  - it compiled just fine.

BeerExpert:
package com.example.model;
import java.util.*;

public class BeerExpert {

    public List getBrands(String color) {
        ArrayList<String> brands = new ArrayList<String>();
        if (color.equals("amber")) {
            brands.add("Jack Amber");
            brands.add("Red Moose");
        }
        else {
            brands.add("Jail Pale Ale");
            brands.add("Gout Stout");
        }
        return(brands);
    }
}

is stored in C:\Apache\Tomcat6\webapps\beer-V1\WEB-INF\classes\com
\example\model\BeerExpert.class, and it compiled just fine.

When I hit the submit button on form.html, I get this HTTP 500 error:
java.lang.NoClassDefFoundError: com/example/web/BeerSelect (wrong
name: BeerSelect)
    java.lang.ClassLoader.defineClass1(Native Method)
    java.lang.ClassLoader.defineClass(Unknown Source)
    java.security.SecureClassLoader.defineClass(Unknown Source)
   
org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappCl
assLoader.java:1815)
   
org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoade
r.java:872)
   
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoade
r.java:1325)
   
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoade
r.java:1204)
   
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.jav
a:105)
   
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:
212)
    org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:
844)
    org.apache.coyote.http11.Http11Protocol
$Http11ConnectionHandler.process(Http11Protocol.java:634)
    org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:
445)
    java.lang.Thread.run(Unknown Source)

I'm not sure what's going on... I can't seem to find what I'm
configuring incorrectly.  Could someone please help?