How to Create and Display Cookies Using Servlets?

The following example code demonstrates How to Create and Display Cookies Using Servlets.

Here is an example of a dynamic web application using servlets to create and display cookies in Java.

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

public class CookieServlet extends HttpServlet {

  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    String name = request.getParameter("name");
    if (name != null) {
      Cookie cookie = new Cookie("name", name);
      cookie.setMaxAge(30 * 24 * 60 * 60); // 30 days
      response.addCookie(cookie);
      response.sendRedirect("/display-cookie");
    } else {
      RequestDispatcher dispatcher = request.getRequestDispatcher("/create-cookie.jsp");
      dispatcher.forward(request, response);
    }
  }
}

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

public class DisplayCookieServlet extends HttpServlet {

  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    Cookie[] cookies = request.getCookies();
    String name = null;
    if (cookies != null) {
      for (Cookie cookie : cookies) {
        if (cookie.getName().equals("name")) {
          name = cookie.getValue();
          break;
        }
      }
    }
    request.setAttribute("name", name);
    RequestDispatcher dispatcher = request.getRequestDispatcher("/display-cookie.jsp");
    dispatcher.forward(request, response);
  }
}

Here is an example of the JSP page, create-cookie.jsp.

<!DOCTYPE html>
<html>
<head>
  <title>Create Cookie</title>
</head>
<body>
  <h1>Create Cookie</h1>
  <form action="/" method="get">
    <div>
      <label for="name">Name:</label>
      <input type="text" id="name" name="name">
    </div>
    <div>
      <button type="submit">Create Cookie</button>
    </div>
  </form>
</body>
</html>

Here is an example of the JSP page, display-cookie.jsp.

<!DOCTYPE html>
<html>
<head>
  <title>Display Cookie</title>
</head>
<body>
  <h1>Display Cookie</h1>
  <p>Name: ${name}</p>
</body>
</html>

In this example, the CookieServlet class creates a cookie and adds it to the response if the name parameter is not null. If the name parameter is null, the request is forwarded to the create-cookie.jsp page, which allows the user to enter a name. The DisplayCookieServlet class retrieves the cookies.

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