Tomcat7 on Ubuntu14.04 html works but 404 error for servlets

Question

I'm new to servlets. I've installed Tomcat7 in Ubuntu14.04 and the service runs fine. But it gives 404(not found) error for servlet (http://localhost:8080/hello/HelloServlet). The html within the application runs fine. So are the Tomcat managerial tools.

Any idea of what I'm doing wrong?

Tomcat webapps structure: /var/lib/tomcat7/webapps

webapps
|-- ROOT
    |-- hello
    |   |-- index.html
    |   `-- WEB-INF
    |       |-- classes
    |       |   |-- HelloServlet.class
    |       |   `-- HelloServlet.java
    |       |-- lib
    |       `-- web.xml
    |-- index.html
    `-- META-INF
        `-- context.xml

web.xml:

<?xml version="1.0" encoding="UTF-8"?>
<web-app 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/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
     version="2.5">
<servlet>
    <servlet-name>HelloServlet</servlet-name>
    <servlet-class>HelloServlet</servlet-class>
</servlet>

<servlet-mapping>
     <servlet-name>HelloServlet</servlet-name>
     <url-pattern>/HelloServlet</url-pattern>
</servlet-mapping>
</web-app>

HelloServlet.java:

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.annotation.WebServlet;

@WebServlet(name="HelloServlet", urlPatterns={"/HelloServlet"})

public class HelloServlet extends HttpServlet{
  private String message;
  public void init() throws ServletException{
      message = "Hello World";
  }
  public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
      response.setContentType("text/html");
      PrintWriter out = response.getWriter();
      out.println("<h1>" + message + "</h1>");
  }
  public void destroy(){

  }
}

localhost:8080/hello/HelloServlet gives the 404 error. Sorry I missed this essential part in the question. — sariDon

sariDon sariDon · Accepted Answer · 2015-09-07T08:53:01

Finally I got it running :)

It was the directory structuring that was creating the problem. The application directory should be just outside the 'webapps/ROOT' directory. To be specific, just put the application directory directly under the 'webapps' (Seems to be specific case for Tomcat7 and Ubuntu 14.04LTS)

The corrected structure:

webapps
|-- ROOT
`-- hello
    |-- index.html
    `-- WEB-INF
        |-- classes
        |   |-- HelloServlet.class
        |   `-- HelloServlet.java
        |-- lib
        `-- web.xml

The previous structure (with error):

webapps
|-- ROOT
    |-- hello
    |   |-- index.html
    |   `-- WEB-INF
    |       |-- classes
    |       |   |-- HelloServlet.class
    |       |   `-- HelloServlet.java
    |       |-- lib
    |       `-- web.xml
    |-- index.html
    `-- META-INF
        `-- context.xml

Tomcat7 on Ubuntu14.04 html works but 404 error for servlets

3 Answers