Problem running a servlet.

Question

I'm seeing a problem while attempting to run a java servlet under eclipse (Ganymede), I'm running Java 1.6 and Apache Tomcat 6.0.

Here is what i am doing:

1. Stop Tomcat.
2. New Dynamic webproject.
3. Call the project TestProject
4. Use default options: Context = "TestProject", Context Directory = "WebContent", Java Source Directory = "src"
5. Right click on project and select new servlet
6. Use default package and call the class "HelloTest" all other options are defult
7. Change URL Mapping to /hello

The Code for the servlet is as follows (I've only edited the doGet and doPost methods everything else is generated):

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class HelloTest
 */
public class HelloTest extends HttpServlet {
    private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public HelloTest() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
     PrintWriter writer = response.getWriter();
     writer.write("Hello World");
     writer.flush();
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
     doGet(request,response);
    }

}

Here is how I try to run the project: 1. Save the project 2. Right click on the project and select run on server. 3. Select existing Tomcat server 4. Click Finish.

When I try to browse to http://localhost:8080/TestProject/hello I get an exception saying that the class was not found.

javax.servlet.ServletException: Wrapper cannot find servlet class HelloTest or a class it depends on
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
java.lang.Thread.run(Thread.java:619)

root cause

java.lang.ClassNotFoundException: HelloTest
    org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1387)
    org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
    org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
    org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
    org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)

Am I doing something wrong?

If I add a .jsp page called test.jsp it displays perfectly, so I know Tomcat is running and serving pages and that I have the right path.

Answer 1

First check if the class is correcty deployed. See also this question.