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View Full Version : not able to access records from mysql database



janunme
04-11-2007, 08:40 AM
i am not bale to solve this problem since two weeks

i am trying to access records from mysql database using jsp. inside this jsp program i wrote all my JDBC code. it is working very nicely and displaying records.

now i wrote all the JDBC code in .java and i am accessing that code in jsp file. but this time i am getting only exceptions not records. i am keeping my programs here. please crosscheck once and tell where i am wrong

code

connect.java
-------------------





package connection;
import java.sql.DriverManager;
import java.sql.Connection;
import java.io.*;
public class connect
{
Connection conn;
public connect()
{
try{
Class.forName("com.mysql.jdbc.Driver");
}
catch(Exception e)
{
System.out.println(e);
}
}
public Connection getConnection()
{
try{
conn=DriverManager.getConnection("mysql:mysql://localhost/hello","root","root");
}catch(Exception e)
{
System.out.println(e);
}
return conn;
}
}

---------------------------------------------------------------
SqlBean.java
---------------



package sq;

import connection.*;
import java.sql.*;

public class SqlBean
{
Connection con=null;

public SqlBean()
{
connect c=new connect();
con=c.getConnection();
}

// it is used to select the records based on Query
public ResultSet selection(String query)
{
ResultSet rs=null;
try
{
Statement st=con.createStatement();
rs=st.executeQuery(query);
//return rs;
}
catch(Exception e)
{
System.out.println(e);
}

return rs;
}

}

--------------------------------------------------

test.jsp
-------------



<%@ page import="java.sql.*" session="false" %>
<jsp:useBean id="s" class="sq.SqlBean" scope="page" >
<% ResultSet rs=s.selection("select name from how");

while ( rs.next() )
{
out.println(rs.getString(1));
}
%>
</jsp:useBean>


and the exceptions what i am getting is




HTTP Status 500 -

--------------------------------------------------------------------------------

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.servic e(JspServletWrapper.java:358)
org.apache.jasper.servlet.JspServlet.serviceJspFil e(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspSe rvlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet .java:856)


root cause

java.lang.NullPointerException
org.apache.jsp.test_jsp._jspService(test_jsp.java: 57)
org.apache.jasper.runtime.HttpJspBase.service(Http JspBase.java:133)
javax.servlet.http.HttpServlet.service(HttpServlet .java:856)
org.apache.jasper.servlet.JspServletWrapper.servic e(JspServletWrapper.java:311)
org.apache.jasper.servlet.JspServlet.serviceJspFil e(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspSe rvlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet .java:856)


note The full stack trace of the root cause is available in the Tomcat logs.


--------------------------------------------------------------------------------

Apache Tomcat/5.0.16



waiting for your valuable replys