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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