java.lang.NoClassDefFoundError

[juturu madhu sudana rao]

Hi,
I am j madhu sudana rao working as a analyst programmer computer based learning sdn bhd in malaysia.Now i am Netbeans 5.0 version and also database mysql5.0 and i am using jar file mysql-connector-java-3.1.12.

I take two Jtextfields and Jbutton.

when click button i want display the records from mysql database,but i got following error

java.lang.NoCla ssDefFoundError : org/aspectj/lang/Signature

import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.sql.Driver Manager;
import java.net.*;
import java.sql.SQLExc eption;

private void btn_displayActi onPerformed(jav a.awt.event.Act ionEvent evt) {
// TODO add your handling code here:
try {
System.out.prin tln("ok");
Class.forName(" com.mysql.jdbc. Driver").newIns tance();
System.out.prin tln("ok");
String url = "jdbc:mysql ://localhost:3306/asset";
Connection conn = DriverManager.g etConnection(ur l,"root","12345 6");
Statement stmt = conn.createStat ement();
ResultSet rs;
rs = stmt.executeQue ry("SELECT username,passwo rd FROM user");

// while ( rs.next() )
// {
//String lastName = rs.getString("L name");
// System.out.prin tln(lastName);

rs.next();
txt_username.se tText(rs.getStr ing("username") );
txt_password.se tText(rs.getStr ing("password") );

// }

conn.close();
}
catch (Exception e)
{
System.err.prin tln("Got an exception! ");
System.err.prin tln(e.getMessag e());
}


}

Please help me as early as possible

Tq
J madhu