Introduction

This tutorial aims to guide you through creating a simple Servlet and deploying it on a server. Servlets are server-side technologies used to extend capabilities of servers that host applications accessed by means of a request-response programming model. They are used to handle requests received from the client, run some business logic, and then send a response back to the client.

You will learn:
- The basics of Servlet programming.
- How to deploy a Servlet on a server.

Prerequisites:
- Basic understanding of Java programming.
- Basic understanding of HTML.
- Apache Tomcat or any other server installed on your system.

Step-by-Step Guide

Servlet programming involves creating Java classes that extend the capabilities of servers that host applications accessed via a request-response model.

Creating a Servlet:
1. First, create a new dynamic web project in your IDE (Eclipse, IntelliJ, etc.)
2. Next, create a new Servlet. You can do this by right clicking on your project -> New -> Servlet. This opens a dialog box where you can enter the 'Package' and 'Class' names.
3. After creating your Servlet, you'll see that it extends HttpServlet and overrides doGet() and doPost() methods. These methods are where you write your business logic.

Deploying a Servlet:
1. After writing your Servlet, you need to deploy it on a server. Most IDEs have servers like Apache Tomcat integrated, making it easier to deploy.
2. To deploy, right-click on your project -> Run As -> Run on Server. Choose the existing server or add a new one.
3. Once the server starts, it will display your output in a browser.

Code Examples

// Import required java libraries
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

// Extend HttpServlet class
public class HelloWorld extends HttpServlet {

  private String message;

  public void init() throws ServletException {
    // Initialization code...
    message = "Hello World";
  }

  public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
    // Set response content type
    response.setContentType("text/html");

    // Actual logic goes here.
    PrintWriter out = response.getWriter();
    out.println("<h1>" + message + "</h1>");
  }

  public void destroy() {
    // Finalization code...
  }
}

In this example, we create a simple Servlet that displays "Hello World". We override init() method for initialization, doGet() for handling GET requests, and destroy() for finalization code.

Summary

In this tutorial, we have learned about Servlet programming and how to deploy a Servlet on a server. The next step would be to learn about ServletConfig, ServletContext, and Session Tracking. You can find more resources on the official Oracle documentation.

Practice Exercises

1. Create a Servlet that takes an input from the user and displays it on the screen.
2. Create a Servlet that counts how many times a user has visited a webpage.
3. Create a Servlet that redirects the user to a different webpage.

Remember, the more you practice, the better you get. Keep practicing and happy coding!