Servlet Query
Monisha Kapur
Greenhorn
Posts: 1
posted 11 years ago
hi
I am new to servlets . My first program executed..
but the second one is having problem as all is going right but when the i submit the uid and pwd through the html i get a blank page.it shows nothing
Servlet Code:
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;
public class login extends HttpServlet
{
public void doGet(HttpServletRequest req,HttpServletResponse res) throws ServletException,IOException
{
String uid=req.getParameter("t1");
String pwd=req.getParameter("t2");
PrintWriter out=res.getWriter();
res.setContentType("text/html");
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con=DriverManager.getConnection("jdbc
dbc:ms","scott","tiger");
PreparedStatement psm=con.prepareStatement("select * from reg where uid1=? and pwd=?");
psm.setString(1,uid);
psm.setString(1,pwd);
ResultSet rs=psm.executeQuery();
if(rs.next())
{
out.println("<html><head><title>WELCOME</title></head>");
out.println("<body><b><i>Hello user "+uid+"</b></i>");
out.println("</body></html>");
}
else res.sendRedirect("http://localhost:8080/login.html");
}
catch(Exception e)
{
e.printStackTrace();}
}
}
plz help me out ...
thanks .
I am new to servlets . My first program executed..
but the second one is having problem as all is going right but when the i submit the uid and pwd through the html i get a blank page.it shows nothing
Servlet Code:
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;
public class login extends HttpServlet
{
public void doGet(HttpServletRequest req,HttpServletResponse res) throws ServletException,IOException
{
String uid=req.getParameter("t1");
String pwd=req.getParameter("t2");
PrintWriter out=res.getWriter();
res.setContentType("text/html");
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con=DriverManager.getConnection("jdbc
dbc:ms","scott","tiger");PreparedStatement psm=con.prepareStatement("select * from reg where uid1=? and pwd=?");
psm.setString(1,uid);
psm.setString(1,pwd);
ResultSet rs=psm.executeQuery();
if(rs.next())
{
out.println("<html><head><title>WELCOME</title></head>");
out.println("<body><b><i>Hello user "+uid+"</b></i>");
out.println("</body></html>");
}
else res.sendRedirect("http://localhost:8080/login.html");
}
catch(Exception e)
{
e.printStackTrace();}
}
}
plz help me out ...
thanks .
Bosun Bello
Ranch Hand
Posts: 1511
posted 11 years ago
I would first verify that the parameters are populated before using them in a query.
String uid=req.getParameter("t1");
String pwd=req.getParameter("t2");
if(your uid and pw fields != null && their length is > 0)
do what ever
Also, thee is a chance that no rows were returned. You need to display something if no rows were found.
String uid=req.getParameter("t1");
String pwd=req.getParameter("t2");
if(your uid and pw fields != null && their length is > 0)
do what ever
Also, thee is a chance that no rows were returned. You need to display something if no rows were found.
Bosun (SCJP, SCWCD)
So much trouble in the world -- Bob Marley
William Brogden
Author and all-around good cowpoke
Rancher
Rancher
Posts: 13078
6
posted 11 years ago
You should also take the precaution of closing the output stream to force flushing of the contents. A simple out.close() will do the trick.
Bill
Bill
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