Database Visit Counter

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Database Visit Counter

Write a Servlet which displays a message and also displays how many times the message has been displayed (how many times the page has been visited). 
  
Hint: Create a file which will update the counter each and every time the page is being loaded. 


(Using Database Connection)

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Step 1: Create a database with name database.mdb , Table name dbCounter , Column name counter with type numeric and add dsn with name db_count.

Step 2: Create VisitCounter.java servlet file which can interact with database for fetching and update counter value. 

package pack6;

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

public class VisitCounter extends HttpServlet
{
public void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException
{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
Connection conn = null;
                Statement stmt= null;
Statement update=null;
ResultSet rs = null;

try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
conn = DriverManager.getConnection("jdbc:odbc:db_count");
stmt = conn.createStatement();
rs = stmt.executeQuery("select * from dbCounter");

if(rs.next())
{
int count = Integer.parseInt(rs.getString(1));
out.println("counter : " +count);
count ++ ;

update = conn.createStatement();
String str = "UPDATE dbCounter SET Counter ="+count;
update.executeUpdate(str);
}
else
{
out.println("Data Not Loaded");
}
rs.close();
stmt.close();
update.close();
conn.close();
}
catch(ClassNotFoundException cnfex)
{
out.println("cnfex : " +cnfex.getMessage());
}
catch(SQLException sqlex)
{
out.println("cnfex : " +sqlex.getMessage());
}
}
}

Step 3: Create WEB.XML file for Mapping Servlet file.

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app>
<servlet>
      <servlet-name>DatabaseVisitCounter</servlet-name>
      <servlet-class>pack6.VisitCounter</servlet-class>
</servlet>  
<servlet-mapping>
        <servlet-name>DatabaseVisitCounter</servlet-name>
        <url-pattern>/Visit</url-pattern>
</servlet-mapping>
</web-app>

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Cookies Visit Counter

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Cookies Visit Counter

Write a Servlet which displays a message and also displays how many times the message has been displayed (how many times the page has been visited). 
  
Hint: Create a file which will update the counter each and every time the page is being loaded. 

(Making use of cookies)

---

Step 1: Create VisitPage.Java using Packages Concepts for servlet which can handle counter variable to keep a track on visits.

package pack5;

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

public class VisitPage extends HttpServlet
{
public void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException
{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String cookieName = "Visit";
Cookie[] cookies = request.getCookies();
if(cookies == null)
{
out.println("Wellcome New User<br>");
Cookie c = new Cookie("Visit","0");
c.setMaxAge(60*60*24*365);
response.addCookie(c);
}
if(cookies != null)
{
for(int i=0;i<cookies.length;i++)
{
Cookie c = cookies[i];
if(cookieName.equals(c.getName()))
{
out.println("Wellcome Back Again..!!<br>");
int count = Integer.parseInt(c.getValue());
out.println("Count :" + ++count);
Cookie repeat = new Cookie("Visit",String.valueOf(count));
repeat.setMaxAge(60*60*24*365);
response.addCookie(repeat);
}
}
}
}
}

Step 2: Create WEB.XML file for Mapping Servlet file.

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app>
<servlet>
      <servlet-name>CookiesVisitCounter</servlet-name>
      <servlet-class>pack5.VisitPage</servlet-class>
</servlet>  
<servlet-mapping>
        <servlet-name>CookiesVisitCounter</servlet-name>
        <url-pattern>/VisitPage</url-pattern>
</servlet-mapping>
</web-app>

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Write a Servlet which displays a message and also displays how many times the message has been displayed (how many times the page has been visited).

---

Write a Servlet which displays a message and also displays how many times the message has been displayed (how many times the page has been visited). 
  
Hint: Create a file which will update the counter each and every time the page is being loaded. 


(Simple Counter Variable is Used Without making use of session , cookies  or database)

---

Step 1: Create VisitCounter.Java using Packages Concepts for servlet which can handle counter variable to keep a track on visits.

package pack4;

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

public class VisitCounter extends HttpServlet
{
private int Count = 0;
public void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException
{
response.setContentType("text/html");
PrintWriter out = response.getWriter(); if(Count > 0)
{
out.println("Wellcome Again ...!");
out.println("<br>Page Visited : " + ++Count+ " Times");
}
else if(Count <= 0)
{
out.println("Wellcome..!!");
out.println("<br>Page Visited : " + ++Count+ " Times");

}
}
}

Step 2: Create WEB.XML file for Mapping Servlet file.

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app>
<servlet>
      <servlet-name>SimpleVisitCounter</servlet-name>
      <servlet-class>pack4.VisitCounter</servlet-class>
</servlet>  
<servlet-mapping>
        <servlet-name>SimpleVisitCounter</servlet-name>
        <url-pattern>/Visit</url-pattern>
</servlet-mapping>
</web-app>

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Write a Servlet to display all the attributes available from headers

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Write a Servlet to display all the attributes available from headers (request and context).
Hint: Make use of getHeader() to get all the related and display all the attributes available in the getHeader() function.
All the attribute:
• Accept
• Accept-Charset
• Accept-Encoding
• Accept-Language
• Authorization
• Connection
• Content-Length
• Host
• Referer
• User-Agent

---

Step 1: Create GetHeader.Java using Packages Concepts for servlet which can handle all header Attributes.

package pack3;

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

public class GetHeader extends HttpServlet
{
public void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException
{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<html><head><title>Header Info Methods</title></head>");
out.println("<body><table align='center' border='2' width='50%' height='50%'>");
out.println("<tr align='center'><td colspan='2'>Header Attributes</td></tr>");
out.println("<tr align='center'><td>Accept :</td><td>"+request.getHeader("Accept")+"</td></tr>");

out.println("<tr align='center'><td>Accept-Charset :</td><td>"+request.getHeader("Accept-Charset")+"</td></tr>");
out.println("<tr align='center'><td>Accept-Encoding :</td><td>"+request.getHeader("Accept-Encoding")+"</td></tr>");
out.println("<tr align='center'><td>Accept-Language :</td><td>"+request.getHeader("Accept-Language")+"</td></tr>");
out.println("<tr align='center'><td>Authorization :</td><td>"+request.getHeader("Authorization")+"</td></tr>");
out.println("<tr align='center'><td>Connection :</td><td>"+request.getHeader("Connection")+"</td></tr>");
out.println("<tr align='center'><td>Content-Length :</td><td>"+request.getHeader("Content-Length")+"</td></tr>");
out.println("<tr align='center'><td>Host :</td><td>"+request.getHeader("Host")+"</td></tr>");
out.println("<tr align='center'><td>Referer :</td><td>"+request.getHeader("Referer")+"</td></tr>");
out.println("<tr align='center'><td>User-Agent :</td><td>"+request.getHeader("User-Agent")+"</td></tr>");
out.println("</table></body></html>");
}
}

Step 2: Create WEB.XML file for Mapping Servlet file.

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app>
<servlet>
      <servlet-name>HeaderAttribute</servlet-name>
      <servlet-class>pack3.GetHeader</servlet-class>
</servlet>  
<servlet-mapping>
        <servlet-name>HeaderAttribute</servlet-name>
        <url-pattern>/GetHeader</url-pattern>
</servlet-mapping>
</web-app>

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Write a Servlet to display all the headers available from request.

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Write a Servlet to display all the headers available from request. 


Hint: display all the header content using all the header function available in the request header.


Display value for all the function:
• getAuthType
• getRemoteUser
• getContentLength
• getContentType
• getHeaderNames
• getMethod
• getRequestURI
• getQueryString
• getProtocol

---

Step 1: Create HeaderInfo.Java using Packages Concepts for servlet which can handle all header functions.

package Package;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class HeaderInfo extends HttpServlet
{
public void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException
{ response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<html><head><title>Header Info Methods</title></head>");
out.println("<body><table align='center' border='2' width='50%' height='50%'>");
out.println("<tr align='center'><td colspan='2'>Header Info</td></tr>");
out.println("<tr align='center'><td>getAuthType :</td><td>"+request.getAuthType()+"</td></tr>");
out.println("<tr align='center'><td>getRemoteUser :</td><td>"+request.getRemoteUser()+"</td></tr>");
out.println("<tr align='center'><td>getContentLength :</td><td>"+request.getContentLength()+"</td></tr>");
out.println("<tr align='center'><td>getContentType :</td><td>"+request.getContentType()+"</td></tr>");
out.println("<tr align='center'><td>getHeaderNames :</td><td>"+request.getHeaderNames()+"</td></tr>");
out.println("<tr align='center'><td>getMethod :</td><td>"+request.getMethod()+"</td></tr>");
out.println("<tr align='center'><td>getRequestURI :</td><td>"+request.getRequestURI()+"</td></tr>");
out.println("<tr align='center'><td>getQueryString :</td><td>"+request.getQueryString()+"</td></tr>");
out.println("<tr align='center'><td>getProtocol :</td><td>"+request.getProtocol()+"</td></tr>");
out.println("</table></body></html>");
}
}

Step 2: Create WEB.XML file for Mapping Servlet file.

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app>
<servlet>
      <servlet-name>HeaderInfo</servlet-name>
      <servlet-class>Package.HeaderInfo</servlet-class>
</servlet>  
<servlet-mapping>
        <servlet-name>HeaderInfo</servlet-name>
        <url-pattern>/HeaderInfo</url-pattern>
</servlet-mapping>
</web-app>

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Change the above program definition implement more than one textbox and other element on the page pass them as a parameter and handle

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Change the above program definition implement more
than one textbox and other element on the page pass
them as a parameter and handle

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Step 1 : Create HTML Page With All Form Elements Such As         TextBox,TextArea,Radio,CheckBox,List With MultipleSelection.

<html>
<head><title>Get Parameter Values</title></head>

<body>
<form action="http://localhost:8080/GetParameters/GetPara" method="post">
<table border="2" align="center" height="50%" width="60%">
<tr align="center">
<td colspan="6" align="center">
<b><u><i>Student FeedBack Form<i><u><b>
</td>
</tr>
<tr align="center">
<td colspan="2">
Name :
</td>
<td colspan="4">
<input type="text" name="txt_name" />
</td>
</tr>
<tr align="center">
<td colspan="2">
Address :
</td>
<td colspan="4">
<textarea rows="5" name="txt_add"></textarea>
</td>
</tr>
<tr align="center">
<td colspan="2">
Sex :
</td>
<td colspan="2">
<input type="radio" name="sex" value="Male" />Male
</td>
<td colspan="2">
<input type="radio" name="sex" value="Female" />Female
</td>
</tr>
<tr align="center">
<td colspan="2">
Hobbies :
</td>
<td>
<input type="checkbox" name="hobbies" value="Volleyball" />VolleyBall
</td>
<td>
<input type="checkbox" name="hobbies" value="Batminton" />Batminton
</td>
<td>
<input type="checkbox" name="hobbies" value="Basketball" />Basketball
</td>
<td>
<input type="checkbox" name="hobbies" value="TableTennies" />TableTennies
</td>
</tr>
<tr align="center">
<td colspan="2">
Subject :
</td>
<td colspan="4">
<select name="subject" multiple>
<option>C
<option>C++
<option>Java
<option>Oracle
<option>Servlet
</select>
</tr>
<tr align="center">
<td colspan="6">
<input type="submit">
<input type="reset">
</td>
</tr>
</table>
</form>
</body>
<html>

Step 2 : Create GetPara.Java which can handle all this form elements and display output in proper html page.

package pack2;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class GetPara extends HttpServlet
{
public void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException
{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String name = request.getParameter("txt_name");
String add = request.getParameter("txt_add");
String address = request.getParameter("txt_add");
String sex = request.getParameter("sex");
String[] hobbies = request.getParameterValues("hobbies");
String[] subject = request.getParameterValues("subject");
out.println("<html><head><title>Get Parameter Values</title></head>");
out.println("<body><table border='2' align='center' height='50%' width='60%'>");
out.println("<tr align='center'><td colspan='6' align='center'><b><u><i>Student FeedBack Submited Details<i><u><b></td></tr>");
out.println("<tr align='center'>");
out.println("<td colspan='2'>Name : </td><td colspan='4'>"+name+"</td></tr>");
out.println("<tr align='center'><td colspan='2'>Address :</td><td colspan='4'>"+add+"</td></tr>");
out.println("<tr align='center'><td colspan='2'>Sex : </td><td colspan='2'>"+sex+"</td></tr>");
out.println("<tr align='center'><td colspan='2'>Hobbies : </td>");
out.println("<td colspan='6'>");
for(int i=0;i<hobbies.length;i++)
{
out.println(hobbies[i] + " ");
}
out.println("</td>");
out.println("</tr>");
out.println("<tr align='center'><td colspan='2'>Subject : </td>");
out.println("<td colspan='6'>");
for(int i=0;i<subject.length;i++)
{
out.println(subject[i] + " ");
}
out.println("</td>");
out.println("</tr>");
out.println("</table></form></body><html>");
}
}

Step 3: Create Web.INF file for Servlet Mapping.

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app>
<servlet>
      <servlet-name>GetParameters</servlet-name>
      <servlet-class>pack2.GetPara</servlet-class>
</servlet>  
<servlet-mapping>
        <servlet-name>GetParameters</servlet-name>
        <url-pattern>/GetPara</url-pattern>
</servlet-mapping>
</web-app>

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Write a Servlet which will display all the parameters which are passed to the servlet page.

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Write a Servlet which will display all the parameters which are passed to the servlet page.

Hint: The previous page which will send the parameter should implement the method GET and the page should contain one textbox and a button. When the button is clicked the servlet page should get opened and should read the value of the textbox passed as an parameter.

Step 1 : Create Simple HTML Page With Form Elements. 

 
<html>
 <head>
  <title>GetParmter Servelt</title>
 </head> 
 <body>
  <form action="http://localhost:8080/GetParameter/GetParameter" method="GET">
   <input type="text" name="txt_value" value="" />
   <input type="Submit" name="btn_value" value="Get Value" />
  </form>
 </body>
</html>

Step 2 : Create Servlet File Which GET Values from this HTML Form.

package pack1;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
public class GetPara extends HttpServlet
{
          public void doGet(HttpServletRequest request,HttpServletResponse response) throws IOException, ServletException
    {
        response.setContentType("text/html");
        PrintWriter out = response.getWriter(); 
 String getValue = request.getParameter("txt_value");
 out.println(getValue);
    }
}

Step 3 : Create Web.XML File.

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app>
<servlet>
      <servlet-name>GetParameter</servlet-name>
      <servlet-class>pack1.GetPara</servlet-class>
</servlet>   
<servlet-mapping>
        <servlet-name>GetParameter</servlet-name>
        <url-pattern>/GetParameter</url-pattern>
</servlet-mapping> 
</web-app>

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Display Hello World using Servlet and implementing Package

Display Hello World using Servlet and implementing Package

Step 1: Create HelloWorld.Java in Package Test

package test;

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


public class HelloWorld extends HttpServlet
{
 public void doGet(HttpServletRequest request, HttpServletResponse response)
    throws IOException, ServletException
    {
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        out.println("");
        out.println("");
        out.println("");
        out.println("");
        out.println("");
        out.println("Hello World!");
        out.println("");
        out.println("");
    }
}

Step 2: Create Web.xml File in Ur Root Folder

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app>
<servlet>
      <servlet-name>HelloWorld</servlet-name>
      <servlet-class>test.HelloWorld</servlet-class>
</servlet>   
<servlet-mapping>
        <servlet-name>HelloWorld</servlet-name>
        <url-pattern>/HelloWorld</url-pattern>
</servlet-mapping> 
</web-app>