In Java web development, handling requests and responses is a core part of building dynamic applications. The most common methods for handling data between the client (usually a browser) and the server are GET and POST.
GET Method
The GET method is used to retrieve data from the server. It appends data to the URL, which means the data is visible in the browser’s address bar. It is commonly used for requesting resources like web pages, images, or search results.
- Data is appended to the URL as query parameters (e.g.,
example.com?name=John&age=25). - GET requests are idempotent, meaning calling the same request multiple times does not change the server’s state.
- There is a size limitation (URL length), so GET is suitable for small amounts of data.
POST Method
The POST method is used to send data to the server, often when submitting forms (e.g., login forms or feedback). Unlike GET, POST data is included in the body of the request, making it invisible in the URL and more secure for sensitive data like passwords.
- Data is sent in the body of the HTTP request.
- POST requests are non-idempotent, meaning submitting the same data can result in different outcomes (e.g., a database update).
- There is no size limitation like GET, making POST ideal for large data.
Handling GET & POST in Servlets
In a Servlet, we handle GET and POST requests using the doGet() and doPost() methods. Here’s a simple example:
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@WebServlet("/example") public class ExampleServlet extends HttpServlet { // Handle GET requests @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String name = request.getParameter("name"); // Retrieve 'name' parameter from the query string response.getWriter().write("Hello, " + name); // Send response back to the client } // Handle POST requests @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String email = request.getParameter("email"); // Retrieve 'email' parameter from the request body response.getWriter().write("Email received: " + email); // Send response back to the client } } |
