I have created a page which has login as well as Signup fields. I validated the login part by using jsp as it has to go through the database for checking for incorrect Username/password combination . Problem arises while validating the Sign up part as after clicking the submit button for sign up it also goes through the jsp code and returns incorrect Username/password combination. So how can I make the jsp code confined to the login submit button.
<html><form name=f1 method=POST action=log.jsp>
<body background="img.jpg">
<div align="right"><b><font size=4 color=#651A0A>
Username  <input type=text name=username>Â
Password Â
<input type=password name=password>Â
</font>Â Â
<script type="text/javascript">
function validateForm()
{
var x=document.forms["f2"]["fname"].value;
if (x==null || x=="")
{
alert("First name must be filled out");
return false;
}
}</script>
<%@ page import="java.sql.*" %>
<%@ page import="java.io.*" %>
<%@ page language="java" session="true" %>
<%
//Getting the text values from create login page
String uname = request.getParameter("username");
String pass = request.getParameter("password");
java.sql.Connection con;
java.sql.Statement s;
java.sql.ResultSet rs , rs1;
con=null;
s=null;
rs=null;
rs1=null;
String u = null;
String p = null;
int i=0;
try{
Class.forName("org.gjt.mm.mysql.Driver");
con = DriverManager.getConnection("jdbc:mysql://127.0.0.1/test","akshay","");
// out.println("1");
}
catch(ClassNotFoundException cnfex)
{
cnfex.printStackTrace();
}
String sql = "select * from us where uname='"+uname+"'";
try{
s = con.createStatement();
rs = s.executeQuery(sql);
while( rs.next() )
{
u = rs.getString("uname");
p = rs.getString("pwd");
//i++;
}
if(uname.equals(u) && pass.equals(p))
{
response.sendRedirect("http://localhost:8080/main.jsp");
}
else
{ %><br><%
out.println("incorrect username/password combination");
}
}
catch(Exception e){e.printStackTrace();}
finally{
if(rs!=null) rs.close();
if(s!=null) s.close();
if(con!=null) con.close();
}
%>
<input type=Submit name=login value="LOGIN" onclick="this.form.target='_blank';return true;">
  </div>
<form name=f2 method=POST action="Serv" onsubmit="return validateForm()" ><table noborder cellpading= 8 width= 100%>
<tr><th align="left"><iframe width = 65% height= 80% name=iframe src="fade1.html" frameborder=0 scrolling=no ></iframe><div align="center">
<a href="main.html" ><button accesskey=a>
<table style="color: white; " align="center" class="border" bgcolor=blue width="100%" background="back/blue_type.png" onmouseover="this.background='back/reset4.jpg'" onmouseout="this.background='back/blue_type.png'">
<tr>
<td width="81%"><font color=white size=1><b>ADVERTISE HERE</b></font></td>
<td width="19%"><img src="back/reset4.jpg" onmouseover="this.src='back/blue_type.png'" onmouseout="this.background='back/reset4.jpg'" /></td>
</tr>
</table>
</button></a>Â Â Â Â Â Â Â Â Â
            </div> </th>
<TD align="right"><br><font size=5 color=white><b><u><rt>SIGN UP</u>Â Â Â Â Â Â Â Â Â Â Â Â Â Â </b></font><br><br><font color=white>
First Name <input type=text name=fname><br>
Last Name <input type=text name=lname><br>
Username <input type=text name=uname><br>
Password <input type=password name=pwd><br><br>
<div align="right">Â Â Â Â Â Â
><input type=submit value="SIGNUP" onclick="f2.action='Serv';return true;">Â Â Â
             </div><br> </td></form>
</html>
1)login.jsp:
<html>
<script>
function validate(){
var username=document.form.user.value;
var password=document.form.pass.value;
if(username==""){
alert("Enter Username!");
return false;
}
if(password==""){
alert("Enter Password!");
return false;
}
return true;
}
</script>
<form name="form" method="post" action="check.jsp" onsubmit="javascript:return validate();">
<table>
<tr><td>Username:</td><td><input type="text" name="user"></td></tr>
<tr><td>Password:</td><td><input type="password" name="pass"></td></tr>
<tr><td></td><td><input type="submit" value="Submit"></td></tr>
</table>
</form>
</html>
<%String msg=request.getParameter("msg");
if(msg!=null){
%>
<label><font color="red"><%=msg%></font></label>
<%
}
%>
2)check.jsp:
<%@page import="java.sql.*"%>
<%
String user=request.getParameter("user");
String pass=request.getParameter("pass");
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/test","root","root");
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from login where username='"+user+"' and password='"+pass+"'");
int count=0;
while(rs.next())
{
count++;
}
if(count>0)
{
out.println("welcome "+user);
}
else
{
response.sendRedirect("login.jsp?msg=Invalid Username or Password");
}
%>
Got it Thanks