Handling GET requests

The GET method is like sending a polite request to the server, saying, "Hey, can I have this webpage, please?" It's perfect for retrieving data without making any changes on the server side. This could be anything from loading a webpage to fetching specific information like search results or user profiles.

Example

Imagine you're building a simple web application that greets users with a personalized message when they visit a specific URL. Let's call it the "GreetingServlet".

java

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

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

        // Get writer object to write HTML response
        PrintWriter out = response.getWriter();

        // Write HTML response content
        out.println("<html>");
        out.println("<head><title>GreetingServlet</title></head>");
        out.println("<body>");
        out.println("<h1>Welcome to GreetingServlet!</h1>");
        out.println("<p>Hello there, visitor! Thanks for stopping by.</p>");
        out.println("</body></html>");
    }
}

In this example, we've created a Java servlet called GreetingServlet. When a GET request is made to this servlet, it responds by generating a simple HTML page with a welcoming message.

Here's a breakdown of what's happening in the code:

We import necessary servlet and IO packages to handle HTTP requests and responses.
We extend the HttpServlet class and override the doGet method, which gets called when the servlet receives a GET request.
Inside the doGet method, we set the content type of the response to text/html since we're going to send back an HTML page.
We obtain a PrintWriter object from the HttpServletResponse object, which allows us to write the HTML response.
Then, we simply write the HTML content using the PrintWriter, including a basic welcome message.

To use this servlet, you would compile it into a .class file and deploy it on a servlet container like Apache Tomcat. Once deployed, you can access the servlet by visiting its URL, and it will respond with the greeting message.

Handling GET requests ​

Example ​

Handling GET requests

Example