Tomcat 404 classNotFoundException in HelloWorld servlet

Question

I see most of similar problems and try most solutions, but nothing has worked for me!

I am completely new in Java EE and this is my first servlet.

This is my servlet that placed in: C:\tomcat\webapps\jspbook\WEB-INF\classes

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;

public class HelloWorld extends HttpServlet {

@Override
public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {

    response.setContentType("text/html");
    PrintWriter out = response.getWriter();

    out.println("<html>");
    out.println("<head>");
    out.println("<title> hello World Title </title>");
    out.println("</head>");
    out.println("<body>");
    out.println("<h1> Hello To World in body!</h1>");
    out.println("</body>");
    out.println("</html>");
   }
}

And this is web.xml file in C:\tomcat\webapps\jspbook\WEB-INF

 <servlet>
    <servlet-name>HelloWorld</servlet-name>
    <servlet-class>HelloWorld</servlet-class>
 </servlet>

 <servlet-mapping>
    <servlet-name>HelloWorld</servlet-name>
    <url-pattern>/HelloWorld</url-pattern>
 </servlet-mapping> 


<welcome-file-list>
<welcome-file> welcome.html </welcome-file>
</welcome-file-list>

</web-app>

Now, when i restart tomcat, and try http://127.0.0.1:8080/jspbook/HelloWorld

At first time Time this is my first error:

type Exception report

message Error instantiating servlet class HelloWorld

description The server encountered an internal error that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Error instantiating servlet class HelloWorld
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
    org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
    org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2462)
    org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2451)
    java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Thread.java:722)

root cause

java.lang.ClassNotFoundException: HelloWorld
    org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1720)
    org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1571)
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
    org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
    org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2462)
    org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2451)
    java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Thread.java:722)

And when i reload the page, this is my second error:

HTTP Status 404 -

type Status report

message

description The requested resource is not available.

What is wrong with my code?

UPDATE:

I create a package and named it com.jspbook and placed it in here C:\tomcat\webapps\jspbook\WEB-INF\classes\com\jspbook\HelloWorld.java

package com.jspbook;

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;

public class HelloWorld extends HttpServlet {

    @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();

        out.println("<html>");
        out.println("<head>");
        out.println("<title> hello World Title </title>");
        out.println("</head>");
        out.println("<body>");
        out.println("<h1> Hello To World in body! </h1>");
        out.println("</body>");
        out.println("</html>");
    }
}

web.xml is here: C:\tomcat\webapps\jspbook\WEB-INF\web.xml

<web-app xmlns="http://java.sun.com/xml/ns/j2ee" version="2.4">

 <servlet>
    <servlet-name>HelloWorld</servlet-name>
    <servlet-class>com.jspbook.HelloWorld</servlet-class>
 </servlet>

 <servlet-mapping>

    <servlet-name>HelloWorld</servlet-name>
    <url-pattern>/HelloWorld</url-pattern>

 </servlet-mapping> 



<welcome-file-list>

<welcome-file> welcome.html </welcome-file>

</welcome-file-list>

</web-app>

I try http://127.0.0.1:8080/jspbook/HelloWorld but the same Error appear!

(There is no compiled class file at all)

Mind if you move your class inside a package and update the web.xml full class name? — Silviu Burcea, Nov 21 '14 at 16:50
Just like @SilviuBurcea said, don't use default package. Check this post for details: http://stackoverflow.com/questions/7674500/tomcat-cant-find-class-that-is-placed-directly-under-classes-folder. — longhua, Nov 21 '14 at 17:25
@SajjadHTLO You need to compile HelloWorld.java and put the class file there. — longhua, Nov 21 '14 at 19:10

score 1 · Accepted Answer · answered Nov 21 '14 at 18:40

1

Please put the servlet in a package. The container is unable to load classes from default package.

answered Nov 21 '14 at 18:40

javaCurious

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Tomcat 404 classNotFoundException in HelloWorld servlet

1 Answers1