Guest Book Application Using Servlets

// guestbk.java //

import java.sql.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class guestbk extends httpservlet
{
Connection con;
public void doPost(HttpServletRequest req,HttpServletResponse res)
throws
IOException,ServletException
{
PrintWriter out=new PrintWriter(res.getOutputStream());
int ctr=0;
res.setContentType("text/html");
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
con=DriverManager.getConnection("jdbc:odbc:booksrc","","");
Statement stmt=con.createStatement();
ResultSet rs=stmt.executeQuery("select * from gbook");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("

GUEST BOOK DETAILS

");
out.println("");
while(rs.next())
{
ctr++;
String email=rs.getString("emailid");
String cmt=rs.getString("comment");
out.println("");
}
out.println("

E-Mail Address	Comment
"+email+"	"+cmt+"

");
if(ctr==0)
out.println("
No Records Found
");
stmt.close();
con.close();
}
catch(SQLException SQLExcep)
{
System.out.println("error");
}
catch(ClassNotFoundException CNFE)
{
System.out.println("error");
}
out.println("");
out.close();
}
}

// submit.java //
import java.sql.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class submit extends HttpServlet
{
Connection con;
public void doPost(HttpServletRequest req,HttpServletResponse res)
throws
IOException,ServletException
{
String str1,str2;
str1=req.getParameter("emailid");
str2=req.getParameter("comment");
System.out.println(str1);
System.out.println(str2);
res.setContentType("text/html");
PrintWriter out=res.getWriter();
out.println("

Guest Book is Successfully
Updated

");
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
con=DriverManager.getConnection("jdbc:odbc:booksrc","","");
Statement stmt=con.createStatement();
ResultSet rs;
int i= stmt.executeUpdate("insert into gbook
values('"+str1+"','"+str2+"')");
if(i==1)
{
System.out.println("ok");
}
stmt.close();
con.close();
}
catch(SQLException SQLExcep)
{
System.out.println("error");
}
catch(ClassNotFoundException CNFE)
{
System.out.println("error");
}}
}

//guestbk.htm//

ENTER YOUR EMAIL ADDRESS



COMMENTS ARE ALWAYS WELCOME

Simple Program in Java to Implement Multithreading

// Multithreading (odd or even)

import java.io.*;
import java.lang.*;
import java.awt.*;
import java.awt.event.*;

class test extends Frame implements ActionListener,Runnable
{
int lower,upper;
Label l1=new Label("ODD");
Label l2=new Label("EVEN");
List lb1=new List();
List lb2=new List();
Button b2=new Button("EXIT");
test(int low,int up)
{
lower = low;
upper = up;
setLayout(new FlowLayout());
setSize(700,700);
setTitle("Thread Demo");
setVisible(true);
add(l1);add(lb1);add(l2);add(lb2);add(b2);
b2.addActionListener(this);
Thread t=new Thread(this);
t.start();


addWindowListener(
new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{ System.exit(0); }
}
);

}
public void actionPerformed(ActionEvent ae)
{
if(ae.getSource()==b2)
System.exit(0);
}
public void run()
{
try
{
if((lower % 2) != 0)
{
lower = lower + 1;
}
while(lower <= upper)
{
Thread.sleep(1000);
lb2.add(String.valueOf(lower));
lower += 2;
Thread.sleep(500);
}
}catch(Exception e){}
}

public static void main(String args[])
{
int lower,upper;
lower = Integer.parseInt(args[0]);
upper = Integer.parseInt(args[1]);
test ob = new test(lower,upper);

if((lower % 2) == 0)
{
lower = lower + 1;
}

try
{
while(lower <= upper)
{
Thread.sleep(1000);
ob.lb1.add(String.valueOf(lower));
lower = lower + 2;
Thread.sleep(500);
}
}
catch(Exception e){}
}

}