Can we define constructor in Servlet class?

Answer Posted / karnakar thallapalli

we can create default constructor and parameterised constructor.my servlet will anyways run and works fine.this question basically test our knowledge on servlet life cycle and how the container instantiate our servlet.but in real time i never recomend this .u may still use this concept in very exceptional cases.
below code

package com.oracle.scwcdtest;

import java.io.IOException;
import java.io.PrintWriter;

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

public class MyServlet extends HttpServlet {

/**
* Constructor of the object.
*/
public MyServlet() {
super();
System.out.println("in default constructor");
}
public MyServlet(String test) {
super();
System.out.println("param constructor");
}

/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}

/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

response.setContentType("text/html");
PrintWriter out = response.getWriter();
out
.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the GET method");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}

/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

response.setContentType("text/html");
PrintWriter out = response.getWriter();
out
.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the POST method");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}

/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {

}

}

Is This Answer Correct ?    4 Yes 2 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

How do you invoke a servelt?

824


What is the difference between encodeRedirectUrl and encodeURL?

828


List the Different types of servlet?

777


Why the concept of single thread model interface is used?

725


What do you mean by web applications? Explain web application directory arrangement?

725


The code in a finally clause will never fail to execute, right?

804


How can we implement a jsp page?

849


What are the different ways we can maintain state between requests?

770


What are the various ways of session supervision in servlets?

738


Explain session tracking and its importance?

733


What is the difference between the http servlet and generic servlet?

865


What is the use of httpservletrequestwrapper and httpservletresponsewrapper?

759


What is meant by Servlet? What are the parameters of service method?

798


What are the new features added to servlet 2.5?

822


How can the session in servlet can be destroyed?

888