java code for React to user form input

import java.util.Enumeration;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class FirstServlet extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {

//set the MIME type of the response to "text/html"
response.setContentType("text/html");

//use a PrintWriter send text data to the client
java.io.PrintWriter out = response.getWriter();

//output the HTML content
out.println("");

out.println("");
out.println("

Please submit your information

");

//make sure method="post" so that the servlet service method
//calls doPost in the response to this form submit
out.println("

+ request.getContextPath() + "/FirstServlet\" >");

out.println("");
out.println("

"); out.println("Your first name:	"); out.println(""); out.println("
"); out.println("Your last name:	"); out.println(""); out.println("
"); out.println("Your email:	"); out.println(""); out.println("
"); out.println("

");
out.println("");
}

public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {

//display the parameter names and values
Enumeration paramNames = request.getParameterNames();

String parName;

boolean emptyEnum = false;
if (!paramNames.hasMoreElements())
emptyEnum = true;

//set the MIME type of the response to "text/html"
response.setContentType("text/html");

//use a PrintWriter send text data to the client
java.io.PrintWriter out = response.getWriter();

//Begin assembling the HTML content
out.println("");
out.println("");

if (emptyEnum) {
out.println("

No parameters

");
} else {
out.println("

Here are the submitted parameter values

");
}

while (paramNames.hasMoreElements()) {

parName = (String) paramNames.nextElement();
out.println("" + parName + " : "
+ request.getParameter(parName));
out.println("
");
}
out.println("");
}
}