Servlet source + web.xml + CLASSPATH all in one example

Tomcat - Configuring Web Applications example from a Well House Consultants training course
More on Tomcat - Configuring Web Applications [link]

Source code: Coffeeweb.java Module: A653

/* ------------------------ Coffeeweb.Java ------------------- */
/*
*/

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

// You can have your compiler find these classes via ...
// export CLASSPATH=/usr/local/tomcat/common/lib/servlet-api.jar

public class Coffeeweb extends HttpServlet{

/* A Coffeeweb is a standard servlet with the following
methods added / replaced ... */

        public static void main (String [] gerald) {

                /* This function is not used when we run
                as a servlet, but can be useful for testing
                the other stuff in the class in a standalone
                mode */

                System.out.println("Greetings World");
                int wide = 4;
                int deep = 3;
                int laptops = workitout(wide,deep);
                System.out.print("The desk should take ");
                System.out.print(laptops);
                System.out.println(" little computers");
                }

        private static int workitout(int w, int d) {
                // Represents the complicated "business logic"

                // If we can fit a lot of computers we had
                // better leave space for a cup of coffee for
                // the guy who is building them all!

                int spaces = w * d;
                if (spaces > 10) spaces = spaces - 1;

                return spaces;
                }

        public void doGet (HttpServletRequest inp,
                        HttpServletResponse outp)
                        throws ServletException, IOException {

                // Handles any GET requests. The look and feel
                // hard coded into the Java is pretty "yuk" but
                // it's fine for a first demo

                outp.setContentType("text/html");
                PrintWriter out = outp.getWriter();
                out.println("<head><title>Laptops on desk</title></head>");
                out.println("<body><h1>Laptop squash</h1>");

                // Run the business logic!
                int numtops = workitout(3,5);

                out.print("There is room for ");
                out.print(numtops);
                out.print(" systems");

                out.println("</body>");
                }

        }

/* ----------- Code to run this from web.xml
(Note - all commented out as far as the Java compiler is concerned!

<web-app>
<servlet>
                <servlet-name>George</servlet-name>
                <servlet-class>Coffeeweb</servlet-class>
        </servlet>
        <servlet-mapping>
                <servlet-name>George</servlet-name>
                <url-pattern>/deskspace</url-pattern>
</servlet-mapping>
</web-app>

*/

Learn about this subject

This module and example are covered on the following public courses:
* Deploying Apache and Tomcat
* Deploying Java Applications on Linux / Unix
Also available on on site courses for larger groups

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