could not find or load main class

could not find or load main class

package tryjsp;
import java.sql.*;
public class DBConn {
Connection db_conn;
public Connection getConnection()
{
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
String url = "jdbc:mysql:///" + "trylnp";
String user = "root";
String pass = "welcome";
db_conn = DriverManager.getConnection(url,user,pass);
if((db_conn != null)&&(!db_conn.isClosed()))
{
System.out.println("Connected...");
}
return db_conn;
}
catch(Exception e)
{
//System.out.println("Error in connecting to database ");
e.printStackTrace();
}
return null;
}
}
THis is my code ,when ever i m running it showing the error "could not
find or load main class" please help me to run my code.