Name List


Name List


September 11, 2021

example java server servlets post

This example uses an HTML form to create a POST request containing the user’s name, and then shows a list of all of the entered names.

index.html contains an HTML form:

<!DOCTYPE html>
<html>
  <head>
    <title>Name Form</title>
  </head>
  <body>
    <h1>What's your name?</h1>

    <form action="/post-name-list/names" method="POST">
      <input type="text" name="name" value="Ada">
      <br><br>
      <input type="submit" value="Submit">
    </form>

    <hr>

    <p>Click <a href="/post-name-list/names">here</a> to see everybody's name.</p>
  </body>
</html>

NamesServlet.java handles the POST request by outputting the user’s name to the response. You can also navigate to /names to see a list of all of the entered names.

package io.happycoding.servlets;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import jakarta.servlet.annotation.WebServlet;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

@WebServlet("/names")
public class NamesServlet extends HttpServlet {

  List<String> names = new ArrayList<>();

  @Override
  public void doGet(HttpServletRequest request, HttpServletResponse response)
      throws IOException {

    response.getWriter().println("<h1>Names</h1>");

    response.getWriter().println("<ul>");
    for (String name : names) {
      response.getWriter().println("<li>" + name + "</li>");
    }

    response.getWriter().println("</ul>");
    response.getWriter().println(
        "Click <a href=\"/post-name-list/index.html\">here</a> to enter another name.");
  }

  @Override
  public void doPost(HttpServletRequest request, HttpServletResponse response)
      throws IOException {

    String name = request.getParameter("name");

    names.add(name);

    response.getWriter().println("<h1>Hello " + name + "!</h1>");
    response.getWriter().println(
        "Click <a href=\"/post-name-list/names\">here</a> to see everybody's name.");
  }
}

name form

hello Ada

name list



Post Requests Examples

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