Monday, 24 March 2014

Servlets : HTTPServlet


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HTTPServlet

 HTTPServlet Project Dir Structure

HTTPServlet

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

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

public class HelloHttpServlet extends HttpServlet
{

  private static final long serialVersionUID = 1L;

  ServletConfig             config           = null;

  public void init( ServletConfig config )
  {
    this.config = config;
    System.out.println("-----------------------------------------------------");
    System.out.println("init method has been called and servlet is initialized");
    System.out.println("-----------------------------------------------------");
  }

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

    System.out.println("-----------------------------------------------------");
    System.out.println("doGet method has been called");
    System.out.println("-----------------------------------------------------");

    response.setContentType("text/html");

    PrintWriter out = response.getWriter();
    out.print("<html><body>");
    out.print("<b>hello HTTP servlet</b>");
    out.print("</body></html>");
  }

  public void destroy()
  {
    System.out.println("-----------------------------------------------------");
    System.out.println("destroy method has been called and servlet is destroyed");
    System.out.println("-----------------------------------------------------");
  }

}

web.xml
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<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" metadata-complete="true" version="3.0">
  <display-name>HelloHttpServlet</display-name>
  <description>
        This is a simple web application with a source code organization
        based on the recommendations of the Application Developer's Guide.
    </description>
  <servlet>
    <servlet-name>HelloHttpServlet</servlet-name>
    <servlet-class>HelloHttpServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>HelloHttpServlet</servlet-name>
    <url-pattern>/helloHttpServlet</url-pattern>
  </servlet-mapping>
</web-app>

index.html
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<!DOCTYPE HTML><html lang="en"><head>
<meta charset="UTF-8">
<title>HelloHttpServlet</title>
</head>
<body>
<p>
<h3>HelloHttpServlet</H3>
<p></p>
<ul>

<li><a href="helloHttpServlet">HelloHttpServlet</a></li>

</ul>
</body></html>

Environment Used: 

JDK version :1.6.0_30
Tomcat version : 7.0.50 

To Download HTTPServletApp Project Click the below link

https://sites.google.com/site/javaee4321/servlets/HTTPServletApp.zip?attredirects=0&d=1 

See also:

  • Servlets Tutorial
  • All Design Patterns Links
    • at

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